Proposal NASA Student Launch Competition

Transcription

1 Proposal NASA Student Launch Competition

2 Table of Contents 1 Summary Team Summary Student Team Leaders Safety Officer Team Structure NAR/TRA Sections Launch Vehicle Summary Payload Summary Facilities Available Facilities and Equipment Available Computers and Software Necessary Personnel Accessibility Standards Safety Safety Officer Duties Use of Materials Use of Facilities NAR/TRA Personnel Duties Communication of Safety Plan Risk Assessment Compliance With Federal, State, and Local Laws Handling of Rocket Motors Range Safety Regulations Launch Vehicle Design Launch Vehicle Overview and Stability Materials Selection and Construction Propulsion Expected Apogee Recovery System Design Tracking of Vehicle Sections Technical Challenges Verification of Requirements Payload Design - Deployable Rover System (DRS) Overview Design Technical Challenges Testing Plan Independent Testing and Validation (INTEV) Testing Plan Project Plan Development Schedule/Timeline Budget Funding Plan Educational Engagement

3 7.5 Rocketry Project Sustainability Plan Appendices Emerson Manufacturing Teaching Laboratory Operating Rules and Procedures List of Chemicals NAR Safety Requirements Compliance Cornell Rocketry Team Safety Agreement

4 List of Figures 1 Team structure with project leads and contributing team members listed Caution statements within procedures Safety Officer (SO) initials required CRT Safety Agreement OpenRocket side view of the proposed launch vehicle design Length Diagram for the Deployable Rover System section. The right side shows lengths visible from the outside of the launch vehicle when in launch configuration, and the left side shows lengths of components inside the airframe Length diagram for the AV bay and booster sections. The right side shows lengths visible from the outside of the launch vehicle when in launch configuration, and the left side shows lengths of components inside the airframe Booster Section of the airframe Filament-wound fiberglass tube Image of proposed 5 in 4:1 ogive fiberglass nose cone with metal tip G10 Fiberglass fins, bulkhead and centering ring. The fins are not representative of the final fin design Thrust Curve of AeroTech L1150R-PS Geometry of fins (units are in inches) Motor Tube with centering rings Overview of Communications System Entire DR system inside airframe Rover outside the airframe (left) and deployment mechanism prior to activation (right) Flowchart of DRS progression The linear actuator in extended position Diagram of linear actuator mechanism The keyed axle and key (left) and the wheel and axle configuration (right) The rover with solar panels unfolded Flowchart of DRS progression Controls system block diagram progression Layout for the Half Duplex wireless radio communication Test Procedure Template CRT Safety Agreement

5 List of Tables 1 Team Mentor and Advisor Information Student Team Leader Information Proposed team organization and duties of members NAR/TRA sections NAR Safety Code Compliance Risk to Personnel Risk to Project Completion Information about the AeroTech L1150R-PS Motor Launch Vehicle Technical Challenges Launch Vehicle Verification of Requirements DRS Decision Matrix Considered Antennas Types Deployable Rover System Technical Challenges Expected Development Schedule Subteam Breakdown and Projected Expenses Projected Income Projected Educational Engagement Schedule NAR Safety Code Compliance Minimum Distance Table within the NAR High Power Rocket Safety Code

6 1 Summary 1.1 Team Summary For the academic year, Cornell Rocketry Team (CRT) will have the mailing address: Upson Hall 141 Hoy Road Ithaca, NY CRT has a Team Mentor and a Team Advisor, as shown in Table 1. Table 1: Team Mentor and Advisor Information Name Dan Sheerer Daniel Selva Professional Title Weill Hall Facilities Supervisor Assistant Professor Position with CRT Team Mentor Team Advisor Contact TRA Number, Certification Level das227@cornell.edu (607) Level 3 Certified, TRA Number: ds925@cornell.edu (607) N/A 1.2 Student Team Leaders The Cornell Rocketry Team has three student team leaders; their information is listed below: Table 2: Student Team Leader Information Name Stephanie Chang Christopher Fedors Bryan Zheng Title with Cornell Rocketry All-Team Leader All-Team Leader All-Team Leader Contact sc2524@cornell.edu (917) cjf83@cornell.edu (661) bz78@cornell.edu (410) TRA/NAR Number, Certification Level Level 1 Certified, NAR Number: N/A Level 1 Certified, TRA Number: Safety Officer The team Safety Officer is Neha Seetamraju (Cornell University, class of 2020), a member of the Deployable Rover System subteam. The academic year is Neha s second on CRT, and she has gone through all mandatory safety trainings for engineering teams. 5

7 1.4 Team Structure Cornell Rocketry Team is comprised of 30 team members, all of whom are registered students at Cornell University in Ithaca, New York. The team is organized into six subteams, each of which is responsible for one or more major projects. All team members are assigned and committed to one subteam and execute the proposed duties for that subteam. A brief description of each subteam is is shown in Table 3. Subteam assignments for individual team members, identified by first name only, are shown in Figure 12. Table 3: Proposed team organization and duties of members Subteam Airframe Deployable Rover System Independent Test and Validation Electrical and Software Communications Business Duties Design, manufacture, and test the launch vehicle airframe and recovery systems. Design, manufacture, and test CRT s competition payload: Deployable Rover System. Ensure that all components across all systems are thoroughly tested and verified. Work closely with members of other subteams to design and build test rigs, write test procedures, and perform tests on actual flight hardware. Design, manufacture, and test electrical systems for the launch vehicle s payload. Develop a system that tracks the location of launch vehicle segments during and after launch. Perform business operations for the team, including budgeting, securing sponsorships, advertising, maintaining the website, and organizing outreach events. Figure 1: Team structure with project leads and contributing team members listed. 6

8 1.5 NAR/TRA Sections Cornell Rocketry Team will work with the NAR/TRA sections listed in Table 4 for purposes of mentoring, review of designs and documentation, and/or launch assistance. Table 4: NAR/TRA sections Section NAR # TRA # Launch Field Location Upstate Rocketry Research Group (URRG) Penn Yan, NY 1.6 Launch Vehicle Summary CRT has selected a 5 diameter launch vehicle made from filament wound fiberglass. The 5 diameter allows the rover to be larger than if a smaller diameter were chosen. Filament wound fiberglass provides strength to reduce the amount of damage the launch vehicle will sustain throughout testing and the competition. The launch vehicle is long and can be separated into two sections. The top section houses the Deployable Rover System throughout the flight, and has a door mechanism that allows the rover to exit the launch vehicle after landing. The bottom section holds the motor and avionics bay. 1.7 Payload Summary CRT has selected the deployable rover challenge for its scored payload. The rover is made up of a narrow chassis connecting two large wheels. During flight, the rover is secured inside the launch vehicle by a linear actuator deployment mechanism. After landing, the system is remotely activated, which causes the linear actuator to push the rover out the end of the airframe. The rover then autonomously travels at least 5 ft away from the launch vehicle before coming to a stop and unfolding the solar panels located on top of the chassis. 7

9 2 Facilities 2.1 Available Facilities and Equipment Main Facility, Equipment, and Hours of Accessibility Cornell Rocketry Team s lab is located in room B05 of Ward Hall on the campus of Cornell University. CRT has 24-hour access to this lab and it is equipped with a hazards cabinet. CRT also has access to a ventilated area in Upson Hall called the Experiential Learning Lab (ELL), which is intended for working with composite materials and epoxy. In this building, there is also a designated spray booth for painting. Access to this area is also 24-hour. Available Facilities, Equipment, and Hours of Accessibility The Emerson Machine Shop, located in Upson Hall, is a facility open to all students who are machine shop certified. Only students with advanced training are permitted to utilize the CNC mill and CNC lathe. The shop contains the following: 6 Bridgeport Manual Mills 1 Okuma CNC Mill 6 Manual Lathes 1 Okuma CNC Lathe 1 Hardinge Manual Lathe 1 Brake 2 Benders 1 Iron Worker 5 Ton Hydraulic Press Precision Grinder Drill Press Many other hand tools and various equipment The shop is opened on the following days and times: Monday-Friday, 8:00am-4:30pm Thursday, 6:00pm-9:00pm Saturday, 8:00am-12:00pm 2.2 Available Computers and Software All Cornell students and personnel have access to a wide variety of computer labs on campus, many of which are open 24 hours. Many of these computers are equipped with a number of relevant programs, including but not limited to: MATLAB SolidWorks ANSYS Microsoft Office CES EduPack 8

10 CHEMKIN-PRO Google SketchUp Pro TOOLMAKER 9.0 Adobe Dreamweaver CS6 Adobe Photoshop CS6 Adobe Illustrator CS6 CRT also has access to SolidWorks on team members personal computers. Upon request, CRT may reserve a room with teleconferencing abilities. Cornell uses the WebEx platform for conferences ( These rooms are also equipped with a projector, which will be utilized during conferences. CRT currently has a website that is hosted on an Academic Server here at Cornell. The website has been developed using a custom PHP/MySQL backend that enables CRT to easily update and post new information. The business team is responsible for keeping the website up to date. The URL for the website is: There is a page on the site dedicated to the NASA SL where the relevant documents are uploaded as they are completed. 2.3 Necessary Personnel Cornell Rocketry Team is a student-run team. To ensure all safety regulations are met, each step of the design process is reviewed by CRT s advisor, Daniel Selva, as well as the safety officer Neha Seetamraju. All of CRT s components are tested prior to launch with the assistance of the NAR/TRA section described in Section Accessibility Standards CRT ensures that all team members are aware of and abide by the laws stated in articles , and of Subpart B of Section 508. Special care will be taken to follow the guidelines in when creating and updating information on CRT s website. 9

11 3 Safety 3.1 Safety Officer Duties CRT s Safety Officer, Neha Seetamraju, will work with the other subteam leaders, team leaders, and team mentors to ensure that safety remains a top priority throughout all stages of this project. Required Training for Safety Officer The Safety Officer has detailed knowledge of the TRA Code for High Power Rocketry, NFPA 1127 (Code for High Power Rocketry) and of the procedures and safety regulations of the NAR. These documents outline safety measures for the construction and operation of high power rockets. It is required that CRT abide by these rules and by those of the Range Safety Officer at the launch site. The Safety Officer is also aware of the purposes and potential hazards of all chemicals and machinery to which the team has access. The Safety Officer is familiar with the Material Safety Data Sheets (MSDS) for each chemical used, and copies of these documents will be kept for reference for team members in lab spaces. In addition, the Safety Officer will be at least level one NAR/TRA certified by the time of the first full-scale launch. Safety Officer Responsibilities The safety officer is responsible for the following: Reviewing the design of the launch vehicle Reviewing and approving launch vehicle assembly procedures Overseeing the following launch vehicle systems: The preparation of the recovery system The preparation and installation of the motor and igniter The preparation of ejection charges Ensuring team compliance with NAR safety guidelines during all project phases Briefing team members before launches and ground tests Ensuring proper safety documentation and PPE is supplied at work spaces Ensuring the clear communication to team members of all CRT safety guidelines Reviewing hazard mitigations Acquiring and managing Material Safety Data Sheets (MSDS) 3.2 Use of Materials Composites Fabrication of the launch vehicle may involve the molding or cutting of fiberglass and carbon fiber. The use of epoxy with carbon fiber or fiberglass can create hazardous fumes which irritate the skin, eyes, or respiratory system. Gloves, masks, and aprons will be worn at all times when these materials are handled. The cutting of fiberglass or carbon fiber creates particulates within the air which can irritate the eyes and respiratory system. Masks and eye protection must be worn at all times when cutting 10

12 fiberglass or carbon fiber. All composites work may only be conducted in the designated composite area with an exhaust hood within the Experiential Learning Lab (ELL). The safety officer and composite area personnel are immediately notified of any spills or hazards. List of Chemicals The following is a list of chemicals that may be used by CRT. Primary safety concerns and hazard mitigation are included for each chemical. MSDS sheets are also provided and are available in all work spaces. 3Fg Swiss Black Powder Manufacturer: POUDRERIE D AUBONNE Distributor: Schuetzen Powder Energetics, Inc. Primary Use: Pyrotechnic ejection charges are used to separate sections of the launch vehicle during flight and release parachutes or other recovery devices. At the launch site, small amounts of black powder will be carefully measured and put into ejection canisters. Primary Concerns: Highly Flammable. Mitigation: Will be properly stored in a location not subject to intense heat or high temperature variations. Extra caution will be taken to prevent spills or other hazardous situations. MSDS: 20Black%20Powder%20SDS.pdf Acetone Manufacturer: Sunnyside Corporation Primary Use: To clean surfaces and brushes after using epoxy. Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves, masks, and aprons will be worn when working with acetone MSDS: Aeropoxy PH3660 Epoxy Hardener Manufacturer: PTM&W Industries Primary Use: This hardener is mixed with the Aeropoxy PR2032 before application. Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves, masks, and aprons will be worn when working with this hardener. MSDS: Aeropoxy PR2032 Epoxy Resin Manufacturer: PTM&W Industries Primary Use: This epoxy resin is applied when molding carbon fiber or bonding fiberglass. After molding, the resin hardens and forms the composite material. Carbon fiber and fiberglass may be used to strengthen the airframe of the launch vehicle. Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves, masks, and aprons will be worn when working with this resin. MSDS: 11

13 Bondo Body Filler Manufacturer: 3M Primary Use: Fills holes or depressions in the airframe and then is sanded smooth. Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves, masks, and aprons will be worn when working with Bondo. MSDS: zu8l00xm8tvn8t9nv70k17zhvu9lxtd7ssssss-- J-B Weld Manufacturer: J-B Weld Company Primary Use: J-B Weld is used to bond surfaces that will experience significant loads and high temperatures during the flight of the launch vehicle. The main application will be to bond the various components of the motor mount together. J-B Weld will also be used to attach pyrotechnic ejection charge canisters to bulkheads inside of the launch vehicle. Primary Concerns: Irritation of skin Mitigation: Gloves and aprons will be worn when working with J-B Weld. MSDS: files/msds/j-b_weld_resin.pdf Loctite Heavy Duty Epoxy Manufacturer: Henkel Corporation Primary Use: 5-15 minute epoxy primarily used to bond small surfaces that do not contribute to the structural integrity of the launch vehicle, such as internal avionics bays and payloads. Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves and masks will be worn when working with epoxy. MSDS (Resin): pdf?busarea=0006&vkorg=3450&matnr= &recndh= &actndh=0&lang=en& COUNTRY=US MSDS (Hardener): DownPdf.pdf?BUSAREA=0006&VKORG=3450&MATNR= &RECNDH= &ACTNDH=0& LANG=EN&COUNTRY=US Slide Epoxease Mold Release Manufacturer: Slide Products, Inc. Primary Use: This product is applied to molds prior to laying up carbon fiber or fiberglass. This allows the easier removal of the carbon fiber or fiberglass from its mold after curing is complete. Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves and masks will be worn when working with mold release. MSDS: Zap Cyanoacrylate (Super Glue) Manufacturer: Pacer Technology Primary Use: Superglue will be primarily used to bond small surfaces that will not experience significant loads nor contribute to the structural integrity of the launch vehicle, such as inside internal avionics bays and payloads. 12

14 Primary Concerns: Irritation of skin, Fumes. Mitigation: Gloves and masks will be worn when working with super glue. MSDS: pdf Zap Kicker CA Accelerator Manufacturer: Pacer Technology Primary Use: This product is used in small amounts to shorten the drying time of Cyanoacrylate (CA), otherwise known as super glue. Primary Concerns: Irritation if inhaled or in contact with skin Mitigation: Accelerator will only be used in a ventilated area. Gloves and masks will be used when working with Accelerator. MSDS: %20-% pdf 3.3 Use of Facilities CRT works closely with Cornell faculty and other Cornell project teams in a number of facilities on campus. CRT will abide by all safety policies for each of these facilities. Cornell University Safety Policies Cornell University Project Team Management has a number of mandatory safety measures in place. These include but are not limited to: Monthly Safety meetings with the Project Team Director and MAE lab manager. Requirement that all labs contain the proper MSDS Binders and forms. Development of Safety Plan Binder that is located in labs next to MSDS information. This Safety Binder contains relevant information and procedures for hazard avoidance. Hazardous Chemical pick up by Cornell University Environmental Health and Safety. Proper waste disposal. Periodic lab inspections by Ithaca Fire Department and Cornell University Environmental Health and Safety. Shop Manager is required to be present during all machining hours. Students may not work alone in any lab space. These measures help ensure a safe environment for all Cornell teams in all of the campus facilities. CRT Lab Space The private lab space for CRT is located within Ward Hall. This lab space is used for the design, prototyping, and assembly of the launch vehicle and its payloads. It is used to store items and raw materials not needed for the immediate construction of the launch vehicle (old launch vehicles, electronics, etc.). Chemicals, composites, and power tools are not be used in Ward Hall due to the building s poor ventilation. These activities are confined to the Experiential Learning Lab. 13

15 Experiential Learning Lab (ELL) All fabrication of the launch vehicle and payloads takes place in the ELL. Before beginning any work in the ELL, team members should identify all required chemicals that are needed for the task. Team members must wear appropriate PPE, as indicated by MSDS and safety binders located within the lab. Team members are not be allowed to use any chemical whose proper use has not been demonstrated to him or her previously, or whose MSDS has not been read by the team member in question. If power tools are required, team members must at minimum wear eye protection and may also put on a mask and apron if necessary. Tools should only be used as intended. Persons are also not allowed to work alone in the ELL. The ELL contains fume hoods and vacuum tables which shall be utilized whenever fiberglass or carbon fiber is cut. These facilities shall be used during any fabrication process which may create particulates in the air. Emerson Machine Shop Students who are working in the machine shop are required to complete a Machine Shop Safety Training course which is provided by Cornell Engineering s Machine Shop. Once the student completes this machine shop training he/she is allowed to work in the machine shop under supervision of the machine shop manager. Since CRT is an official project team at Cornell, students are required to complete an in-depth safety training session which overviews machine shop safety, proper handling of tools, lab safety and handling of chemicals. The shop manager is required to be present during all hours of shop operation. Personal Protective Equipment (PPE) is available at the machine shop entrance and is required to be worn at all times while in shop. All students with access to the machine shop have read and agreed to abide by the safety regulations given in Section 8.1: Emerson Manufacturing Teaching Laboratory Operating Rules and Procedures. 3.4 NAR/TRA Personnel Duties NAR/TRA personnel are members of the team who have been certified to the level necessary to launch the competition launch vehicle. These personnel are responsible for: Purchasing, handling, storing, and assembly of all rocket motors. Handling and wiring all ejection charge igniters. Handling ejection charges and loading ejection charges. Being present during all ground testing. Signing off on all Standard Operating Procedures and ensuring that NAR/TRA Safety regulations are followed. The NAR/TRA personnel will be in charge of ensuring that all safety precautions are taken into account. The High Power Safety Code of the National Association of Rocketry (NAR) provides a summary of safe practices for launching high power rockets from NFPA It is a requirement of both the NAR and TRA safety codes that NFPA 1127 is obeyed. 14

16 NAR Safety Code Compliance Table 5: NAR Safety Code Compliance NAR Code Certification. I will only fly high power rockets or possess high power rocket motors that are within the scope of my user certification and required licensing. Materials. I will use only lightweight materials such as paper, wood, rubber, plastic, fiberglass, or when necessary ductile metal, for the construction of my rocket. Motors. I will use only certified, commercially made rocket motors, and will not tamper with these motors or use them for any purposes except those recommended by the manufacturer. I will not allow smoking, open flames, nor heat sources within 25 ft of these motors. Ignition System. I will launch my rockets with an electrical launch system, and with electrical motor igniters that are installed in the motor only after my rocket is at the launch pad or in a designated prepping area. My launch system will have a safety interlock that is in series with the launch switch that is not installed until my rocket is ready for launch, and will use a launch switch that returns to the off position when released. The function of onboard energetics and firing circuits will be inhibited except when my rocket is in the launching position. Misfires. If my rocket does not launch when I press the button of my electrical launch system, I will remove the launcher s safety interlock or disconnect its battery, and will wait 60 seconds after the last launch attempt before allowing anyone to approach the rocket. Compliance Only team members with appropriate Level 1 certification will handle and launch on rocket motors over class H. Only team members with Level 2 certification will handle and launch on rocket motors over class J. Only Team Mentor Dan Sheerer (Level 3 certified) will handle and launch on rocket motors over class M. Airframe subteam lead and team leads are responsible for using appropriate materials on the launch vehicle. Only certified motors will be purchased, and motors will only be handled by TRA/NAR personnel. These motors will be stored appropriately. At launch, the Range Safety Officer will have say over all safety issues. The Safety Officer and Team Leads are responsible for ensuring that igniter installation is performed in compliance with the NAR Safety Code. This requirement will be followed. The Range Safety Officer has the final say on all misfires. 15

17 Launch Safety. I will use a 5-second countdown before launch. I will ensure that a means is available to warn participants and spectators in the event of a problem. I will ensure that no person is closer to the launch pad than allowed by the accompanying Minimum Distance Table (Table 19). When arming onboard energetics and firing circuits I will ensure that no person is at the pad except safety personnel and those required for arming and disarming operations. I will check the stability of my rocket before flight and will not fly it if it cannot be determined to be stable. When conducting a simultaneous launch of more than one high power rocket I will observe the additional requirements of NFPA Launcher. I will launch my rocket from a stable device that provides rigid guidance until the rocket has attained a speed that ensures a stable flight, and that is pointed to within 20 degrees of vertical. If the wind speed exceeds 5 miles per hour I will use a launcher length that permits the rocket to attain a safe velocity before separation from the launcher. I will use a blast deflector to prevent the motor s exhaust from hitting the ground. I will ensure that dry grass is cleared around each launch pad in accordance with the accompanying Minimum Distance table (Table 19), and will increase this distance by a factor of 1.5 and clear that area of all combustible material if the rocket motor being launched uses titanium sponge in the propellant. Size. My rocket will not contain any combination of motors that total more than 40,960 N-sec (9208 pound-seconds) of total impulse. My rocket will not weigh more at liftoff than one-third of the certified average thrust of the high power rocket motor(s) intended to be ignited at launch. This requirement will be followed. The Range Safety Officer will have the final say on all Launch Safety. All launches will be conducted at the Upstate Research Rocketry Group (Tripoli Prefecture 139) launch field. This launch field is stocked with proper launching equipment. The Range Safety Officer at the launch field will determine if it is safe to launch. This requirement will be followed. The Team Leads will require that the design of the launch vehicle adheres to these constraints. 16

18 Flight Safety. I will not launch my rocket at targets, into clouds, near airplanes, nor on trajectories that take it directly over the heads of spectators or beyond the boundaries of the launch site, and will not put any flammable or explosive payload in my rocket. I will not launch my rockets if wind speeds exceed 20 miles per hour. I will comply with Federal Aviation Administration airspace regulations when flying, and will ensure that my rocket will not exceed any applicable altitude limit in effect at that launch site. Launch Site. I will launch my rocket outdoors, in an open area where trees, power lines, occupied buildings, and persons not involved in the launch do not present a hazard, and that is at least as large on its smallest dimension as onehalf of the maximum altitude to which rockets are allowed to be flown at that site or 1500 ft, whichever is greater, or 1000 ft for rockets with a combined total impulse of less than 160 N-sec, a total liftoff weight of less than 1500 grams, and a maximum expected altitude of less than 610 meters (2000 ft). Launcher Location. My launcher will be 1500 ft from any occupied building or from any public highway on which traffic flow exceeds 10 vehicles per hour, not including traffic flow related to the launch. It will also be no closer than the appropriate Minimum Personnel Distance (Table 19) from the accompanying table from any boundary of the launch site. Recovery System. I will use a recovery system such as a parachute in my rocket so that all parts of my rocket return safely and undamaged and can be flown again, and I will use only flame-resistant or fireproof recovery system wadding in my rocket. Recovery Safety. I will not attempt to recover my rocket from power lines, tall trees, or other dangerous places, fly it under conditions where it is likely to recover in spectator areas or outside the launch site, nor attempt to catch it as it approaches the ground. The Range Safety Officer will have the final say on launch direction and wind speed considerations. All launches will be conducted at the Upstate Research Rocketry Group (Tripoli Prefecture 139) launch field. This launch field is large enough to satisfy all minimum requirements for CRT s planned launches. The Range Safety Officer at the launch field will determine if it is safe to launch. All launches will be conducted at the Upstate Research Rocketry Group (Tripoli Prefecture 139) launch field. This launch field is stocked with proper launching equipment, and the equipment will be set up the appropriate distance from any buildings. The Range Safety Officer at the launch field will determine if it is safe to launch. The Safety Officer and Team Leads will make sure that all designs adhere to this requirement. The Range Safety Officer will have the final say. CRT will adhere to this requirement during all launches. 17

19 Hazardous Materials Handling Only TRA/NAR members are allowed to handle motors and pyrotechnic devices. These members have read the following: Code of Federal Regulation 27 Part 55: Commerce in Explosives and NFPA 1127 Code for High Power Rocket Motors. TRA/NAR members and the Safety Officer ensure the team abides by the NAR High Power Safety Code and the rules of the RSO at launches. Team members using chemicals will have read the corresponding MSDS and wear correct PPE. Team members will also follow the rules of Cornell lab spaces when working with hazardous materials. 3.5 Communication of Safety Plan The safety officer is in charge of the clear and efficient communication of this safety plan to all team members. The safety officer will also ensure full team compliance with all safety protocols. The following sections indicate the plan for the communication and enforcement of CRT s safety plan. Hazard Recognition and Accident Avoidance By Cornell policy, all project team members must attend a safety meeting upon joining any project team. This meeting covers common hazards, accidents, and incidents, and the mitigation thereof. In addition to Cornell s required safety meeting, CRT members will also attend an internal team safety meeting. At this meeting, the team members will be required to review and sign CRT s safety agreement, displayed in Section 3.5. At this meeting the safety officer will also give a brief safety talk outlining proper safety procedures. Before being allowed access to any materials, new team members will be briefed on the purpose of each material CRT will use. They will also have proper handling of materials demonstrated to them by experienced team members. If at any time any safety risk is observed or an accident occurs, efforts will be taken to mitigate the risk and the safety officer will be notified immediately. Once the situation has been dealt with, affected parties and the Safety Officer will meet to discuss the incident and possible ways to mitigate the risk of a second occurrence. If repeated incidents occur to the same team members consistently, punitive action will be taken as necessary. All of the MSDS forms, located in Section 3.2 of this proposal, and other necessary safety forms are kept in binders located in lab spaces where any fabrication of launch vehicle components is being conducted. Before any hazardous chemicals or materials are handled, each team member will refer to this binder. This policy will ensure that all team members are aware of any potential danger prior to beginning work. Pre-Launch Briefings Pre-launch briefings include an overview of safety procedures and of the rules associated with the intended launch site. Team members will also be briefed on the TRA Code for High Power Rocketry and NASA SL Safety Regulations. Team members will be reminded that all RSO rules are final and that anyone showing inappropriate behavior will not be allowed to launch their rockets and may be required to leave. Briefings will also include an overview of launch procedures, the goals of the launch, and the 18

20 expected outcome. All team members will also be given a copy of the launch checklist to be read prior to launch. Caution Statements in Working Documents When cautionary statements or warnings are necessary in procedure documents, checklists, and other working documents, such warnings will be indicated either in red or highlighted in yellow. These colors will ensure that all warnings are easily visible, even upon a cursory glance. An example of such a warning can be seen below in Figure 26. Figure 2: Caution statements within procedures Some procedure steps will require the signature or initials of the Safety Officer before the step can be considered complete. These steps will be clearly marked in the rightmost column, as shown below. Figure 3: Safety Officer (SO) initials required Compliance with Safety Plan All CRT members must sign and abide by the Cornell Rocketry Team Safety Agreement, which is shown below. 19

21 Figure 4: CRT Safety Agreement 20

22 3.6 Risk Assessment Table 6: Risk to Personnel Hazard Cause Risk Mitigation Injury from Chemicals Injury from Machinery Injury from Unstable Rocket Flight Injury at Test Launch Injury during Ground Testing Spills, Contact with Skin/Eyes, Fume Inhalation Fatigue, Lack of Knowledge, Improper use of tools Moderate Moderate Read MSDS. Wear appropriate gloves, eye protection, clothing, and masks. Members must pass a safety class to work in the machine shop. Eye protection will be worn. Stability < 1.0 cal Unlikely Simulate CP prior to launch. Mark CG after assembly. Bystanders unaware of safety procedures Procedures not followed correctly. Members unaware of surroundings. Unlikely Moderate Members shall read the TRA safety code prior to launch. All testing procedures shall be documented beforehand and reviewed by the Safety Officer. Table 7: Risk to Project Completion Hazard Cause Risk Mitigation CRT is prohibited from continuing the project. CRT fails to comply with NASA SL or Cornell University policies. Unlikely CRT will comply with all Cornell and NASA SL policies. Motor CATO during full scale launch destroys launch vehicle and payload. Faulty rocket motor, Improper handling of rocket motor. Moderate All motors will be commercially purchased from a reputable vendor. Motors will be prepared under the supervision of the Safety Officer and Team Mentor. 21

23 3.7 Compliance With Federal, State, and Local Laws CRT will conduct test launches only at sites hosted by either the National Association of Rocketry or the Tripoli Rocketry Association. These sites will have obtained the necessary FAA waivers to launch high power rockets. The team will abide by the rules of the launch site and will only fly in safe weather conditions after considering wind and local visibility. CRT will not launch a vehicle that has the potential to exceed or approach the maximum altitude granted to a launch site by a waiver. 3.8 Handling of Rocket Motors Purchase and Storage All purchases, storage, transportation, and use of rocket motors and energetic devices will be done by the proper NAR/TRA personnel. Motors casings and reloads will be purchased and handled by the Team Mentor, Dan Sheerer, who is a level 3 TRA certified member. Motors will either be bought on-site, shipped directly to the launch site, or stored by the Team Mentor. All ejection charges will be properly stored away from any sources of ignition or heat. Motors will remain disassembled and in original packaging until immediately prior to launch. Motors will also be stored at a temperature between 45 F and 100 F and away from external sources of flame or heat. Igniters will be stored separate from the motor and from any ejection charges. Handling and Use A high power motor will not be used in a launch vehicle without prior simulation of the flight using that motor. Only NAR/TRA members will handle motors. Only motors which NAR/TRA members are certified to handle will be used. The preparation of rocket motors for all launches will be overseen by both the Team Mentor and the Safety Officer, and team members will follow previously prepared checklists and procedures while preparing the launch vehicle and motor. Transportation In the United States, APCP is excluded from the Department of Alcohol, Firearms, & Tobacco s list of explosive materials. Therefore, it will be shipped to a designated location so it is there upon our arrival prior to launch, or transported by car. During transport, extra precaution will be taken to ensure hazardous materials are kept away from sources of flame or heat. Since CRT will not use the fuel for commercial purposes, no special permits or licenses are required. 3.9 Range Safety Regulations As stated in the Cornell Rocketry Team Safety Agreement, all CRT team members will abide by the NASA SL range safety regulations. All team members understand and agree that: 1. Range safety inspections will be conducted for each vehicle before it is flown. Each team shall comply with the determination of the safety inspection. 22

24 2. The Range Safety Officer has the final say on all rocket safety issues. Therefore, the Range Safety Officer has the right to deny the launch of any vehicle for safety reasons. 3. Any team that does not comply with the safety requirements will not be allowed to launch their vehicle. 23

25 4 Launch Vehicle Design 4.1 Launch Vehicle Overview and Stability Dimensions and Stability Figure 5: OpenRocket side view of the proposed launch vehicle design The total length of the launch vehicle is 106.7, with a diameter of The launch vehicle can be broken into three major sections, excluding the nose cone: the airframe attached to the nose cone, which contains two parachutes and the rover; the AV bay, which is positioned between the two airframe sections; and the booster section, which contains two more parachutes, the motor tube, and its mounting equipment. Using estimated payload masses and known material densities, OpenRocket calculates the center of gravity (CG) to be and the center of pressure (CP) to be from the tip of the nose cone. The static margin of stability of the launch vehicle can be calculated using the following equation, where S is stability, x cp and x cg are the location of the CP and CG respectively, and d is the diameter of the launch vehicle: S = x cp x cg (1) d Using the projected CG and CP, the stability is calculated to be 3.32 calibers. S = in in 5.15 in = 3.32 cal (2) After motor burnout, the CG shifts to 48.73, increasing the stability to 5.13 cal. Vehicle Overview Deployable Rover System 24

26 Figure 6: Length Diagram for the Deployable Rover System section. The right side shows lengths visible from the outside of the launch vehicle when in launch configuration, and the left side shows lengths of components inside the airframe. The rover ejects from the interior of the launch vehicle after landing via a remotely activated trigger. It then autonomously moves at least 5 ft away from the launch vehicle and extends foldable solar panels after stopping. Figure 6 shows the relevant lengths of the deployable rover section. The fiberglass ogive nose cone houses the TRACER. In the launch configuration, the nose cone airframe slides 3 onto the nose cone and is held in place by friction and a nose cone wrap. The Deployable Rover System is secured between two bulkheads inside the nose cone airframe. At apogee, an ejection charge separates the nose cone from the nose cone airframe and pulls out the forward LV drogue parachute as well as the forward LV main parachute secured by two Jolly Logic Chute Releases in series. The parachute releases are put 5 in series for redundancy. The nose cone is tethered to the airframe via a 20-ft long, 16 Kevlar shock 9 cord, which is attached to the nose cone drogue parachute, and an 18 -long, 32 Kevlar shock cord, which is attached to the nose cone main parachute. 25

27 AV Bay Section Figure 7: Length diagram for the AV bay and booster sections. The right side shows lengths visible from the outside of the launch vehicle when in launch configuration, and the left side shows lengths of components inside the airframe. The AV bay houses the electronics that activate the ejection charges. They are housed in an 11 coupler tube, which slides 5 forward into the nose cone airframe and 5 aft into the booster section. The tube contains a 1 -long switch band. It is secured at both ends by 2-56 nylon shear pins. At apogee, an ejection charge below the nose cone is ignited by the AV bay at its forward end, separating the nose cone from the nose cone airframe. The nose cone is tethered to the nose cone airframe and to the parachutes, which are pulled out of the airframe when the blast charge separates the nose cone airframe. 26

28 Then, another ejection charge completely separates the AV bay from the nose cone airframe. Lastly, another ejection charge separates the AV bay from the booster section, pulling out the drogue parachute and the main parachute. The AV bay remains tethered to the booster section. The main parachutes for both the nose cone airframe and parachute as well as the booster section and AV bay are secured with two Jolly Logic Chute Releases in series each, which do not open immediately. The AV bay contains a 3D printed ABS plastic sled, which supports two 9-volt batteries, two altimeters, two switches, and some sections designated for ballast mass. The multiple altimeters are linked to redundant charges to ensure ejection is successful. The sled is secured by 1 4 threaded steel rods. The switches to the altimeters are accessible through the switch band, and static ports are drilled into the switch band to equalize the pressure around the altimeters with atmospheric pressure. G10 fiberglass bulkheads shield the AV bay on either end from ejection charges and provide a location to mount charge wells, terminal blocks, and eyebolts. The G10 fiberglass bulkheads are secured to the AV bay using hex nuts on threaded steel rods, ensuring an airtight seal for the altimeters within the AV bay. Booster Section Figure 8: Booster Section of the airframe The booster section houses the motor, a drogue and main parachute, and a radio tracker. It also serves as a mounting point for the fins The forward end of the booster section slides 5.0 onto the AV bay coupler tube and is secured with shear pins. The furthest forward component in the booster section is a long Kevlar shock cord, which is attached to the drogue parachute. The shock cord is attached to an eyebolt mounted on the aft bulkhead of the AV bay. Quick links are used to connect the drogue 27

29 parachute to a 25-ft-long 1/2 Kevlar shock cord, which is attached to the main parachute for the booster section. Nomex parachute protectors are included for both parachutes. The booster section airframe is 45.5 long, with three rail buttons and slots for four fins. Three centering rings center the 3 diameter motor tube, which will house the 75 mm L1150R-PS motor. The motor tube extends beyond the aft end of the airframe and contains the tail cone retainer. 4.2 Materials Selection and Construction The launch vehicle s materials and construction methods are based on CRT s experience and lessons learned in previous launch vehicles. A fiberglass airframe provides the reliability and robustness required to survive multiple launches. Materials Selection Prefabricated G12 fiberglass tubes with outer diameter 5.15 and inner diameter 5 will be used to construct the launch vehicle airframe, as seen in Figure 9. The use of prefabricated tubes reduces the mass of the launch vehicle and saves CRT a significant amount of time compared to using custom-built airframe. The layup facilities at Cornell University do not permit the fabrication of filament-wound fiberglass tubes, which have a much higher strength-to-weight ratio than tubes made with techniques available to us. Figure 9: tube Filament-wound fiberglass Figure 10: Image of proposed 5 in 4:1 ogive fiberglass nose cone with metal tip As shown in Figure 10, the nose cone has an ogive shape. Additionally, it is made of fiberglass. 28

30 Figure 11: G10 Fiberglass fins, bulkhead and centering ring. The fins are not representative of the final fin design. G10 fiberglass is used to construct the four fins, bulkheads, centering rings, and other inner structural components of the launch vehicle airframe, as seen in Figure 11. G10 fiberglass is a high-strength material that will reduce the probability of fin flutter during flight. The fins are inserted into slots cut into the booster tube. Fiberglass parts are significantly thinner and lighter than plywood parts, increasing the launch vehicle s volume and mass margins. The charge canisters are fixed to avionics (AV) bay bulkheads. The charge canisters are made of PVC that has been tested for the canisters rated charges and are manufactured by Apogee. Two ASTM A193 Grade B7 steel threaded rods, secured to the bulkheads on both ends of the AV bays, pass through the ABS plastic AV sled, and the rods bear the load associated with parachute deployment. The rods bear the load because the parachutes exert force on the bulkheads, and the bulkheads are fastened by the rods. Construction Methods The fins must be built robustly to withstand the force of aerodynamic drag on the fins and any impacts the fin might sustain during flight. CRT uses high-strength Aeropoxy (ES6209) to form two sets of internal fillets and one set of external fillets, ensuring that the fins do not detach from the launch vehicle during flight. Furthermore, possible axial movement of the fins during construction is constrained by the motor mount centering rings. Additionally, CRT has developed a fin alignment jig to ensure that the fins remain in place during application and hardening. The jig will be constructed of laser-cut plywood and will slide over the launch vehicle body and hold the fins in place during construction. The fin slots in the booster tube will be cut using a Dremel The AV sled will be 3D printed as a monolithic component from ABS plastic, reducing assembly time and increasing durability. The ABS plastic construction of the AV sleds prevents damage to sensitive electronics. As an extra precaution, any openings in the AV tube bulkheads will be sealed with epoxy to prevent damage by hot gases from the ejection charges. The Stratasys uprint 3D printer in Cornell s Rapid Prototyping Lab will be used to manufacture the AV sleds. The use of 3D printing allows CRT to easily iterate upon the design if necessary. CRT will be machining additional components for the launch vehicle, including ballast, in the Emerson Laboratory at Cornell. 29

31 4.3 Propulsion Motor Selection The proposed launch vehicle launches on an AeroTech 75 mm L1150R-PS. An AeroTech motor is selected because AeroTech is a well established and trusted motor producer. While a 75 mm motor increases the overall length of the launch vehicle, the estimated apogees calculated using 75 mm motors are closer to the target apogee of 1 mile than the 98 mm motors. The L1150R-PS is selected because its thrust profile resulted in simulated launches reaching an apogee closest to 1 mile. Additionally, it fulfills all safety requirements, as shown below: Table 8: Information about the AeroTech L1150R-PS Motor Total Impulse Avg. Thrust Max. Thrust Burn Time Launch Mass Empty Mass 3517 N-s 1150 N 1346 N 3.1 s oz 62.5 oz Figure 12: Thrust Curve of AeroTech L1150R-PS Sample Calculations Thrust-to-weight ratio can be found by dividing T avg W = 1150 N oz = 7.45 (3) oz 1 N 30

32 The rule of thumb for thrust-to-weight ratio is to be greater than 5, so 7.45 is a sufficient thrust-toweight ratio. The OpenRocket simulation calculates a rail exit velocity of 76.3 fps. This velocity satisfies NASA s minimum rail exit velocity of 52 fps at rail exit. Booster Section Figure 13: Geometry of fins (units are in inches) The fins are G10 fiberglass cut into trapezoidal shapes. Each fin has a root chord length of 7, the tip chord has a length of 3.5, and the height of the fin is 4.5, as seen above in Figure 13. The fins are through-the-wall fins that fit through the fin slots in the booster section. This configuration increases the strength of the fin connection to the launch vehicle, preventing damage on recovery. The fins have tapered leading and trailing edges, which are applied in order to decrease the drag experienced by the launch vehicle. 31

33 Motor Tube Figure 14: Motor Tube with centering rings A 3D model of the motor tube can be seen above in Figure 14. The motor tube is a 3 diameter fiberglass tube which houses the 75-mm L1150R-PS motor along with its casing. The motor tube will be centered using three fiberglass centering rings, which will be attached using epoxy and filleted to give a strong connection. The tail cone retainer serves multiple purposes. First, it retains the motor, preventing accidental ejection of the motor and the motor casing. Next, the shape of the tail cone reduces drag on the launch vehicle. Finally, the tail cone retainer serves the purpose of a thrust ring, transmitting thrust straight to the airframe and decreasing the shear experienced by the fiberglass centering rings. 4.4 Expected Apogee Using estimated masses and dimensions, OpenRocket calculates an estimated apogee of 5335 ft in 5 mph winds and an estimated apogee of 5237 ft in 15 mph winds. If the launch vehicle reaches over a mile, more ballast mass can be added to the AV Bay section. If the launch vehicle does not reach a mile, motor with a larger impulse will be selected, such as an AeroTech L850W. 4.5 Recovery System Design The launch vehicle uses a dual-deploy recovery system. Drogue parachutes for the launch vehicle are deployed at apogee to prevent excessive acceleration before main deployment. NASA has placed a 75 ft-lb maximum kinetic energy constraint on independent sections at landing. The maximum landing 32

34 speed for all the independent sections can be calculated using the equation below. KE = 1 2 mv2 (4) This is a sample calculation for the maximum booster section landing speed: KE = 75 ft-lb KE = 1 2KE mv2 v = m = = ft/s The parachute size that would allow the sections to land at the above speeds is calculated using the equation below 8mg D = πρc d v 2 (5) where D is the parachute diameter in feet, m is the launch vehicle mass in slugs, g is the acceleration of gravity, ρ is the density of air (CRT assumes a constant air density of slug/ft 3, which is the ground-level density, for ease of calculation), C d is the drag coefficient (1.5 for dome parachutes), and v is the speed at impact with the ground in ft/s. This equation is chosen because parachute vendors conventionally sell parachutes specified by their diameters. Below is a sample calculation for the booster section parachute size: 8mg D = πρc d v 2 = = ft = Using equation 4, the maximum LV nose cone section velocity is ft/s. The minimum required parachute diameter is ft = The proposed launch vehicle design includes two main parachutes and two drogue parachutes. One main and one drogue parachute are located between the Deployable Rover System and the nose cone. The other main and drogue parachutes are located aft of the AV bay in the booster section. A piston is used to separate the AV bay from the nose cone airframe. It is located between the AV Bay and the Deployable Rover System so that the blast charge does not not damage the Rover system. Another blast charge is located below the nose cone to eject it at apogee, which allows the main and drogue parachutes exit the airframe. The drogue deploys at apogee and the main parachute is held closed by two Jolly Logic Chute Releases in series until deployment. Another blast charge is located below the AV bay which allows the AV bay to separate from the booster section. The AV bay is tethered to the booster section, allowing the booster section drogue and main parachute to deploy. The booster section main parachute is also held closed by two Jolly Logic Chute Releases in series until deployment. The size of the parachutes is heavily dependent on the final mass of the launch vehicle. This means that the emphasis on lightweight construction minimizes the size of the parachutes. The parachutes are oversized by five percent, allowing for a small margin of error in the simulation and ensuring a safe landing velocity. The proposed parachute sizes for the booster section are (main) and 20 (drogue). The proposed parachute sizes for the LV Nose cone section are (main) and 20 (drogue). 33

35 The Kevlar shock cords, shroud lines, and parachutes are purchased from vendors due to the difficulty of fabricating these components in Cornell s laboratory facilities. The launch vehicle uses forged steel quick links, swivels, and eyebolts. The use of swivels prevents tangling and twisting of the shock cord and shroud lines. The eyebolts are fastened to bulkheads with nuts and epoxy. 4.6 Tracking of Vehicle Sections Figure 15: Overview of Communications System The Communications System is tasked with fulfilling and conforming to all goals that are set by NASA in sections 2.11 and 2.12 in the Statement of Work. As stated in Launch Vehicle Overview and Stability, all untethered sections of the launch vehicle must be tracked. CRT will meet the requirement by installing two different radio beacons in all untethered sections of the launch vehicle. The Simple Radio Beacon (SRB) will act as a backup radio beacon if the GPS Radio Beacon (GRB) malfunctions after launch. In addition to these systems, a custom-designed Tracking Electronics Module will be developed by CRT to track the booster and middle sections of the launch vehicle. The GRB will be the primary radio used by CRT. With the current GRB, CRT can quickly narrow the search range to an area of about 20 meters. From there, the SRB can be used if the launch vehicle is in an obscure environment. The GRB will draw more power than the SRB, so a larger battery will need to be used to power it. The SRB is a BigRedBee 100 mw BeeLine transmitter. The transmitter operates on the 70-centimeter radio band and will constantly transmit the morse-code signal of its operator. The transmitter requires very little power and has the capacity to last many hours beyond expected flight time. The battery can be expected to have a capacity of around 150 mah. The SRB s signals will be received by a directional 34

36 antenna attached to an attenuator. This will allow CRT to track the launch vehicle by using the direction of strongest signal. Finally, the Tracking, Arc & Gyro, video Capture, Electrical Recovery (TRACER) system will be located near the nose cone of the launch vehicle. The TRACER will record GPS position, accelerometer data, and video. The GPS data will be transmitted back to the ground via RF transmission and recorded on a computer. The TRACER system will be operated by an Arduino Mega, which will serve as the hardware interface and will store collected data for retrieval after the launch vehicle has landed. The camera in the TRACER system will be operated by a Raspberry Pi computer, which will allow the video stream to be saved locally. The radio for data trasmission will be a LoRa RFM98W. The sensors included in the TRACER will be an Adafruit GPS module, a Raspberry Pi camera, and a gyroscope and accelerometer module. As per section 2.12 in the NASA SL Statement of Work, all of CRT s radio frequency emitting devices are located in physically separate compartments. In addition, a Faraday cage will be used to shield the critical on-board components (such as altimeters) from any emissions from the radio beacons. 4.7 Technical Challenges Table 9: Launch Vehicle Technical Challenges Challenge AV bay deploys the drogue parachute at apogee. AV bay bulkhead caps will withstand the shock cord forces. The launch vehicle will reach apogee of 5,280 with the Deployable Rover System. The launch vehicle must house the Deployable Rover System (with associated electronics). The launch vehicle must be able to separate and deploy parachutes with black powder charges. The launch vehicle must provide adequate initial thrust to maintain stability. Solution The altimeters in the AV bay will have the drogue channel set for apogee. The caps will consist of fiberglass bulkheads which will withstand the load exerted on them. An L1150R-PS will propel the launch vehicle housing the Deployable Rover System to 5,280 ft. The Deployable Rover System dimensions will be constrained to fit within the launch vehicle. There will be adequate black powder to separate the sections but not enough to cause damage. Calculations will ensure an appropriate amount of black powder is used, and ground testing will be used to verify this design. Calculations are used to determine an appropriate motor to give a stable thrust-to-weight ratio and test launches will confirm this. 35

37 Motor tube must be able to securely hold motor in place under the force of launch. Fin alignment must be symmetrical so flight path is accurate. Bulkheads must securely hold shock cords and be able to withstand deployment forces. Avionics must fire black powder charges to separate sections for parachute deployment at correct heights. The motor mount is designed to have a motor retainer that will hold the motor in place. A fin alignment mechanism built by CRT will be used to align the fins. Fiberglass bulkheads will be used for their robustness. Altimeters are programmed to fire the black powder charges at apogee (5,280 ft). 4.8 Verification of Requirements Table 10: Launch Vehicle Verification of Requirements Requirement The vehicle shall deliver the Deployable Rover System to an apogee altitude of 5,280 ft above ground level (AGL). [NASA SL 2.1] Each altimeter shall be armed by a dedicated arming switch exterior of the airframe when the launch vehicle is in launch configuration on the launch pad. [NASA SL 2.3] The launch vehicle shall be designed to be recoverable and reusable. Reusable is defined as being able to launch again on the same day without repairs or modifications. [NASA SL 2.6] The launch vehicle must be able to withstand impacts on landing and loads during launch. [NASA SL 2.6] The launch vehicle shall have a maximum of four independent sections. An independent section is defined as a section that is either tethered to the main vehicle or is recovered separately from the main vehicle using its own parachute. [NASA SL 2.7] Design Feature(s) to Satisfy Requirement An L1150R-PS motor is used to launch the 34.7 lb launch vehicle to 5,280 feet. The avionics bay is located in its airframe component such that the altimeter switch can be fixed on the interior of the airframe tube. This way the switch is accessible from the outside through an especially designated opening. Trackers are placed within the launch vehicle to make it recoverable. The airframe materials are selected taking into account durability. The parachutes are sized such that each component will land with less than 75 ft-lb. of kinetic energy. Launch vehicle is built robustly to withstand impact. Independent (both tethered and separate) sections are limited, and subsystems are organized efficiently in order to minimize the number of sections. 36

38 The launch vehicle shall be capable of being prepared for flight at the launch site within 4 hours, from the time the Federal Aviation Administration flight waiver opens. [NASA SL 2.9] The launch vehicle shall be capable of remaining in launch-ready configuration at the pad for a minimum of 1 hour without losing the functionality of any critical on-board component. [NASA SL 2.10] The launch vehicle shall have a minimum static stability margin of 2.0 at the point of rail exit. [NASA SL 2.16] The launch vehicle shall accelerate to a minimum velocity of 52 fps at rail exit. [NASA SL 2.17] The launch vehicle shall stage the deployment of its recovery devices, where a drogue parachute is deployed at apogee and a main parachute is deployed at a much lower altitude. [NASA SL 3.1] At landing, each independent section of the launch vehicle shall have a maximum kinetic energy of 75 ft-lb. [NASA SL 3.3] The recovery system electrical circuits shall be completely independent of any payload electrical circuits. [NASA SL 3.4] The recovery system shall contain redundant, commercially available altimeters. The term altimeters includes both simple altimeters and more sophisticated flight computers. [NASA SL 3.6] The launch vehicle is prepared for launch (black powder charges inserted, etc.), minimizing number of tasks executed from the time the FAA flight waiver opens. Commercial batteries are selected so that any critical on-board electronic component have sufficient battery life. Launch vehicle center of gravity is from the center of pressure, which is greater than two launch vehicle diameters above the center of pressure. Motor is selected to satisfy this requirement, in accordance to all other constraints on launch vehicle (mass, friction). The OpenRocket simulation calculates a rail exit velocity of 76.3 fps. This velocity satisfies NASA s minimum rail exit velocity of 52 fps at rail exit Launch vehicle is equipped with avionics bays and altimeters which deploy each section at apogee and between ft. Parachutes are sized such that all independent sections land with less than 75 ft-lb of kinetic energy. Recovery system electrical circuits are placed separately from all other electrical elements and are insulated from all electromagnetic interference. Each recovery device is deployed by its respective avionics bay, which includes two altimeters: one primary and one redundant. 37

39 An electronic tracking device shall be installed in the launch vehicle and shall transmit the position of the tethered vehicle or any independent section to a ground receiver. [NASA SL 3.10] The recovery system electronics shall not be adversely affected by any other on-board electronic devices during flight (from launch until landing). [NASA SL 3.11] Tethered sections are equipped with a tracking system that signals the location. Recovery system electronics are placed in a different section from all onboard transmitting devices and are properly shielded from electromagnetic waves with appropriate insulation materials. 38

40 5 Payload Design - Deployable Rover System (DRS) 5.1 Overview For the launch vehicle s scored payload, CRT has chosen Option 2: Deployable rover. DRS Mission Requirements 1. After landing and upon receiving a signal, the rover must deploy from within the launch vehicle. 2. The rover must autonomously move at least 5 ft away from the launch vehicle. 3. Upon stopping, the rover must extend solar panels. System Summary Figure 16: Entire DR system inside airframe The Deployable Rover System (DRS) is comprised of two distinct mechanisms: a linear actuator for deployment and the rover itself. During the launch vehicle s flight, the deployment mechanism secures the rover in place using two bulkheads, one on either side of the rover. The rover is further constrained by two long steel rods running through the chassis and wheel, one of which is threaded. After landing, CRT manually sends a remote signal to the system. This triggers a DC motor, which turns the threaded rod to push the rover and its housing out of the end of the airframe, as explained below. Once the rover is fully out of the airframe, the rover drives away from the launch vehicle. 39

41 Figure 17: Rover outside the airframe (left) and deployment mechanism prior to activation (right). The rover moves itself using two 4.25 diameter wheels on each end of a 4.5 wide, 2 thick chassis. The chassis is heavier on the bottom than on the top, with a third wheel extending from the center. These two traits keep the chassis upright, preventing the body from simply spinning in place. Once the rover drives the required 5 ft from the launch vehicle, it autonomously stops and unfolds the solar panels. Figure 18: Flowchart of DRS progression Tradespace CRT has considered a number of locations on board the launch vehicle for the DRS: the nose cone, the booster section, and a section between the booster and nosecone. The primary factors in selecting a location for the rover ae availability of space and ease of rover deployment. The nose cone has less available space to fit the rover, and the irregular diameter would likely add complexity to the design of the deployment mechanism. The booster section is far larger than the nosecone and is a uniform shape. However, deployment methods are limited by the motor and fins at one end. Additionally, the fins prop up the rear end of the section, and any attempt to exit from the front end would likely get stuck in the ground due to the resulting angle. Housing the rover in the mid-section opens up the option of 40

42 deploying from either end in addition to from the side. However, including a middle section increases the complexity of the launch vehicle, resulting in three sections that must each be attached to a parachute. CRT is also considering obstacle detection and steering on the rover. It would be simple both mechanically and electronically to simply allow the rover to drive in a straight line for a certain period of time. Without the need for steering, the entire rover could be powered with a single motor, significantly reducing the mass of the system. Additionally, including obstacle detection and steering would require additional sensors, additional motors, and additional coding. However, it also drastically increases the likelihood of successfully navigating variable terrain. Without steering, the rover could easily become stuck on an obstacle with no way to resolve the situation. Design Consideration Confidence in success Size of housing area Ease of rover deployment Integration with airframe Integration with electrical systems Expected weight Expected size of rover Weighting Table 11: DRS Decision Matrix House in booster section House in middle section No steering x x4 4 4 x x x x x3 4 3 Total Steering Based on the results of Table 11, the DRS is housed in the middle section of the launch vehicle. Additionally, the rover has sensors to detect obstacles in order to perform basic maneuvers to avoid them. 5.2 Design 41

43 Linear Actuator Figure 19: The linear actuator in extended position CRT considered a variety of methods by which to secure the rover inside the launch vehicle prior to deployment. One approach is to only constrain the rover with a bulkhead at the open end so as to prevent it from falling out prematurely. This is a relatively easy mechanism to release but may expose the rover to damage. CRT also considered latching the rover in place via the wheels. However, any latches would have to be sturdy enough to securely hold the rover, while also being flexible or maneuverable enough to release easily when desired. One of the most significant challenges is to release the rover from the inside of the launch vehicle after landing. This requires the housing section to offer an opening of sufficient size for rover exit. Additionally, the airframe must remain structurally capable of launch/recovery despite whatever openings are created for rover exit. Another obstacle is ensuring that the opening is not obstructed due to the landing orientation of the launch vehicle. One way to ensure that the opening of the section is not obstructed at landing would be to control the landing orientation. This introduces new challenges, as it would likely require sensing and mechanisms dedicated to reorientation. Thus, CRT has not selected this route, given that there are options (introduced below) for deploying a rover in arbitrary landing orientation conditions. There are several possible designs that involve opening an actuated door on the face of the airframe, such as the airframe splitting about a hinge, like a clam shell, or such as a hinged door flap that is part of the airframe. These designs compromise the structure of the airframe. A previous CRT payload involved a hinged airframe flap functioning as a door, which required extensive reinforcement and analysis to ensure it maintained its geometry and functionality. Furthermore, actuated doors on the airframe rely on the section landing with a particular orientation in order to ensure the rover can be released from the opening. The remaining option is to open the ends of the section by removing a bulkhead after landing. The simplest way to do this is via a linear actuator that pushes a bulkhead at the end of the housing section. Furthermore, this linear actuation can be used not only to release the rover, but also to deploy it. That is, the rover can sit in a housing that is pushed out of the launch vehicle section along with the bulkhead, 42

44 so that not only is the housing section open for rover exit, but the rover does not have to do any special maneuvers to exit, as it has been pushed out of the housing section already. Figure 20: Diagram of linear actuator mechanism To accomplish this, a housing (green in Figure 20) is pushed by a nut on the lead screw. The housing consists of two columns supporting bulkheads at both of their ends end. The rotation of the lead screw (via a DC motor) causes the housing to translate axially along the launch vehicle section, moving the rover housing with it (pushed by the rightmost bulkhead). By this translation, the rover housing is pushed outside the launch vehicle section. The rover becomes free to drive out of the housing. Because the lead screw extends through the rover housing, CRT must be careful to avoid interference between the rover and the lead screw. The currently selected method is to have cutouts through the rover wheels for the lead screw. The consequence is that the lead screw cannot be concentric, because this would force it to penetrate through critical rover elements, like the wheel axle. Thus, to prevent binding of the housing/bulkheads upon their translation out of the launch vehicle section due to the eccentric pushing force, a shaft parallel to the lead screw is implemented, along with matching collars on the housing. The shaft also supports the cantilever weight of the housing section and mitigates bending/deflection of the lead screw under this loading. This shaft must also extend through another set of cutouts in the rover wheels. Another requirement that results from this design is that the structure bridging the bulkheads is either sparse or nonexistent, such that the rover does not encounter it as an obstacle after the housing has exited the launch vehicle section. Chassis A number of designs were considered during the rover design process; however, some constraints needed to be taken into consideration. Space is a significant concern, as the rover needs to be secured within a 5.15 diameter launch vehicle. Many designs, such as a standard four-wheel chassis, are not viable with such a small space constraint, as they lose functionality and reliability when scaled down to such a small size. 43

45 Another constraint taken into consideration was the ability of the rover to correct its orientation. As such, CRT considered designs capable of correcting their own position should they flip over. Research into such systems uncovered designs using spring-loaded flipping mechanisms for remote-controlled (RC) cars. However, the idea was discarded due to its non-reusable nature, as it is possible that the rover will flip multiple times and because it would not be useful if the rover was oriented incorrectly on landing. A system that uses mechanical arms to right the rover was also considered, but is likely to involve many moving parts that are prone to failure. Some RC cars have round protrusions covering the top of their chassis. As a result, should they flip over, their position will be unstable and they are likely to roll back into the correct orientation. However, designing a vehicle whose shape will cause it to return to the correct orientation that fits within the diameter of the launch vehicle would require an extremely small chassis that would seriously limit the rover s ability to complete its task. The proposed rover will consist of a 4.5 long chassis with one wheel on each side and a third wheel protruding from the center, as shown in Figure 17. It will be secured parallel to the airframe of the launch vehicle. This design will allow CRT to vary the length of the rover as needed by the systems onboard the rover, with the only constraint being the length of the airframe section containing the rover. This is useful as the wheels will be constrained only by the diameter of the airframe, rather than being constrained by both diameter and the position of the wheels within the airframe. A two-wheel design also addresses the concern of steering and orienting the rover, as a two-wheel system solely relies on the angular velocities of each wheel relative to each other to steer and drive. Between the two wheels will be a heavy mid-section, with its center of gravity below the axis of the wheels. This will cause the rover to naturally tend towards an upright position. In the case that the rover encounters an obstacle or terrain that causes the vehicle to tip forward or backward, a protruding wheel from the mid-section will prevent it from fully flipping over, and the forward momentum of the rover along with the heavy weight of the mid-section will revert it to an upright position. Wheels CRT has considered various methods of propulsion for the rover. One such method involves a sharp, curved arm, similar to a pickaxe, that would hook onto the ground and pull the rover forward. However, this was found to be too complex and unreliable as it could lead to several failures, such as the rover getting caught on something in its path or the pickaxe being unable to pull it forward. Another method that CRT looked into was legs. This option was ruled out due to it requiring more parts and being mechanically complicated. Next, CRT considered using a reaction wheel to propel the rover forward. Here, the rover would be of a cylindrical shape with a rough outer surface to act like one big wheel. However, this design was not chosen as it requires the motor to frequently accelerate and decelerate to achieve the necessary angular acceleration for the desired torque. The rover must overcome the negative angular acceleration caused by frictional forces, and driving at constant speed will not generate any torque. Finally, CRT thought about adding tank treads on the rover due to their ability to more easily traverse any rough terrain that the rover might encounter. This method was not chosen as tank treads can easily break and become unaligned. In the end, CRT has decided on using wheels, more specifically one on each side of the rover, as seen in Figure 17. Having the two wheels as opposed to four allows for the rover to orient itself while still possibly being able to climb over bumps in its path. A third wheel protrudes from the center of the chassis that is meant to reorient the rover by reacting off the ground when the rover tips forward or 44

46 backward. It also helps prevent the rover from spinning in place should it get stuck. Figure 21: The keyed axle and key (left) and the wheel and axle configuration (right). The wheels shown in Figure 21 have 4.25 diameters and are fitted with rubber wheel treads for better traction. The axle to which the wheels are connected has a cylindrical cross section with a keyseat cut out of it. Each wheel has a matching keyway so that it can fit tightly over the axle and cannot twist off. Furthermore, the rover has sensors and other electronic equipment so that it can automatically steer itself while avoiding any potential obstacles on the field. Solar Panels Figure 22: The rover with solar panels unfolded. CRT considered three options for the solar panel system. The first is to mount the solar panels onto a motorized track and extend them along the tracks after the rover is far enough from the launch vehicle. 45

47 The major disadvantages of this system are the mechanical complexity of motorized tracks, the large amount of space on the rover that the tracks would require, and the challenge of mounting motors to power the system. CRT is still considering a second alternative of dropping solar panels behind the rover once it is five feet away and pulling them behind the rover to unfold them. The primary advantage of this system is extremely simple deployment, as the panels can be pushed off the rover and the forward motion of the rover will unfold the panels behind it. The primary disadvantage of this system is the potential for the panels to be damaged while being pulled along the ground behind the rover, though CRT is confident that suitably durable panels could be found or protective enclosures could be constructed. Furthermore, since the panels must be deployed after the rover is sufficiently far from the launch vehicle, another disadvantage is that the rover must move further than the target distance after the panels are deployed. The final option CRT considered is a simple folded-over design. Two panels will lay flat on top of each other, photosensitive surfaces touching, and will then be actuated apart once the rover is sufficiently far away from the launch vehicle. The primary advantage of this design is its extreme simplicity, it requires only hinges and a simple actuator. The consequences of choosing this system are that the rover must maintain its orientation so the solar panels are exposed to the sun and that space must be found to mount a motor to power the system. CRT is certain that these disadvantage can be resolved, particularly through the chosen chassis design. The stabilizing wheel allows small movements either forward or backward to return the rover to the correct orientation. As the panels will be relatively small, CRT believes that a small servo motor mounted on the exterior of the rover chassis will be sufficient to actuate the panels. A servo motor does not take up significant space on the chassis and should be easily mounted. Additionally, it may be possible to mount the motor internally which may allow for better waterproofing and easier mounting of the motor. CRT is planning to make the solar panels usable by using a Thin Film Transistor (TFT) Liquid Crystal Display to represent data from the solar panel. This display is being considered due to its small size and clear display. A larger display would need more power as well as more space. An LED matrix was also considered for use. This option was rejected since an LED Matrix is much more limited in the data it can display. The TFT Display is smaller and can display more data. The display will be powered from a power source within the rover. Waterproofing While it is unlikely that the rover will need to contend with rainfall, it is very likely that it will encounter mud or puddles of water. In this event, the electronics of the rover need to be protected from the elements. One potential approach is to design the chassis so that it forms a hollow container that the electronic components can be placed in. Another is to cover the system with a tight-fitting waterproof cover, similar to shrink wrap. This method has the drawback of prohibiting access to the covered systems and would only be applied shortly before competition. However, these approaches can be combined by creating a cover over most, but not all, of the rover. A small opening is then left in the cover to act as an access hatch, permitting CRT to manipulate electronics as needed. The hatch needs to be sealed tightly, but the chassis in general may be constructed with slightly looser tolerances. 46

48 Controls The controls system is responsible for coordinating all of the events after the launch vehicle has landed, including driving the rover 5 ft away from the launch vehicle and deploying the solar panels. This task requires control logic for scheduling all the events as well as real time data processing for navigation. In order to accomplish this task, a microcontroller will be used. Microcontrollers have the flexibility necessary to both coordinate the tasks the rover must complete while simultaneously navigating the rover across the possibly rough terrain it encounters. Sensors will also need to be incorporated into the controls systems in order to determine when the rover has left its housing as well as measure the rover s distance from the launch vehicle after it begins moving. Additional sensors for obstacle avoidance may also be incorporated. Figure 25 shows the system level connections for the controls system. Figure 23: Flowchart of DRS progression Current candidates for the controls system s microcontrollers are the ATMega328p, PIC32, and Raspberry Pi. These microcontrollers all have the computational ability to control the rover, but each has its own advantages and drawbacks. The ATMega328p has a well developed software ecosystem and requires the least supporting hardware, but it is also relatively slow compared to the other controllers with a maximum clock speed of 20 MHz. The PIC32 is faster than the ATMega328p and offers many useful peripherals, but requires significantly more hardware to support and does not have a very active software ecosystem. The Raspberry Pi has the most computational power and its own operating system, but is extremely large and consumes significant amounts of power. The most desirable characteristics for these microcontrollers is small form factor and reliability while still being capable of complex instruction sets. The entire controls system must be as small as possible to save space for the battery and motors used to power the rover. This also means that the microcontroller should have as little supporting circuitry as possible, as this will both reduce size and increase reliability. Since the rover only has several tasks to keep track of, and the computations needed for navigation will calculated at a low frequency, speed is not a primary concern. High processing power is still desirable, since it allows for the use of more advanced navigation and obstacle avoidance algorithms; consequently, the high memory capacities of 47

49 these controllers are also helpful in storing more complex algorithms. Finally, all these microcontrollers are heavily used chips which means that each has an enormous amount of documentation and libraries built up by its user base. Figure 24 shows the connections between the microcontroller module and the other systems on the rover. Figure 24: Controls system block diagram progression The controls system requires two sets of sensors, one to determine when the rover is out of its casing, and another to keep track of the distance the rover has traveled. For the rover deployment sensors, two options have been examined: a physical switch that is triggered when the rover leaves the launch vehicle, and solar sensors that detect when the rover is no longer covered by airframe. The physical switch is much simpler and more reliable from an electrical standpoint, but may be a challenge to integrate mechanically into the rover design. The only mechanical requirements of the solar sensors is that they remain unobstructed. Unfortunately these sensors can be obstructed by dust and are subject to changes in weather. Clouds could cause the sensor to think that it is still inside the airframe. Some form of isolation will added between the microcontroller and motor modules to ensure that the microcontroller will not be affected by noise, voltage spikes, and current spikes generated by the motors. The most likely candidates are H-bridges and optoisolators for motors and servos respectively. Steps will be made to isolate the motor s power supply from the microcontrollers. Object Avoidance CRT is planning to implement basic object avoidance on the rover. This can be achieved by use of distance sensors. The sensors will detect if an obstruction is directly in front of the rover and the control system will turn the rover accordingly. CRT considered two sensors for use: ultrasonic sensors and infrared sensors. The ultrasonic sensors have a faster response time and are more costly that infrared sensors. Infrared sensors have a simpler implementation and work very well within close distance ranges. Based on the data from the sensors, the control system will instruct one wheel to rotate slower in order to execute a turn until the object is no longer in the path of the rover. This system is designed to ensure that the rover will have the ability to move five feet without the potential of having its movement impeded by obstacles. 48

50 Motors CRT is currently considering using either DC motors or servos to drive the wheels of the rover. One of the most important factors in CRT s motor decision will be the balance between directional control and size constraint. A DC motor would provide more torque than a servo and is smaller than a servo motor of the same capacity, given the servo motor s additional circuitry and casing. However, if CRT decides to implement directional control of the rover, a DC motor would also require external circuitry. CRT would need to construct an H-Bridge circuit using transistors in order to control the direction that the motor rotates in. Since space is limited within the rover, this could present an issue. This circuit would also require more space in the rover, making servo motors are smaller and more lightweight by comparison. Each wheel can be connected to a different motor in order to allow them to be controlled separately. This gives the rover the ability to turn. The rover can turn by either stopping one wheel completely and rotating the other, or by rotating one wheel slightly slower. The second method allows the motor to change directions more smoothly. The average power to the motor can be controlled using pulse width modulation (PWM) of the voltage supplied. By changing the duty cycle of pulses sent to the motor, the motor s speed can be smoothly adjusted. The motor for the linear actuator will be similar to the motors used for the wheels of the rover, but it must provide more provide more torque than the wheel motors, For this reason it requires more power. Stability and power take precedence over directional control, as the actuator only needs to go in a single direction. For this reason, DC motors may be preferable to servos for the actuator. Additionally, CRT is considering including another small motor for the deployment of the solar panels. For this, the precision provided by a servo motor would be sufficient, should CRT choose to use one. A servo motor can adjust the panels to a precise angle, if required. Wireless Communication To initiate the deployment of the rover, CRT is considering using wireless radio communication. CRT also considered infrared communication. However, this method was not selected because it requires a direct line-of-sight for the communication, which is not a guaranteed condition. 49

51 Figure 25: Layout for the Half Duplex wireless radio communication. For wireless radio communication CRT is considering two options: Half Duplex, and Simplex. Simplex communication is the easiest method to implement as well as the most cost effective. However, the major disadvantage to this method is that it only allows for one-way communication. CRT would only have the ability to send a start signal to the rover with no confirmation response back. The Half Duplex method gives CRT the ability to both send and receive messages. Using this method, CRT can receive a signal confirming the start of the linear actuator. This confirmation helps with testing, making it easier to determine any problems the system may run into. Also, when the rover is deployed, visual confirmation may not be possible, so the confirmation serves to acknowledge that rover has exited the launch vehicle. The layout for Half Duplex communication can be seen Figure 25 in above. For communication, an antenna is used for transmission and receiving. It is optimal for the antenna to be housed within the launch vehicle near the circuitry for the linear actuator. There are many different types of antennae that CRT is considering. The antennae must have a frequency in the range for radio transmission and receiving. CRT also needs to consider the radiation pattern. It should not be focused in a specific direction. Additionally, the antenna needs to be small, but still able to transmit and receive over at least two miles. Table 12: Considered Antennas Types Type of Antennas Half-Wave Dipole Half-Wave Folded Dipole Short Dipole V-Antenna Loop Antenna Frequency Range 3 KHz to 300 GHz 3 KHz to 300 GHz 3 KHz to 30 MHz 3 to 30 MHz 300 MHz to 3 GHz Radiation Pattern Omnidirectional Omnidirectional Omnidirectional - Radiation is low Bidirectional Omnidirectional if loop is horizontal 50

52 Length Half of the wavelength Half of the Wavelength Wire that leads to antenna must be less than one-tenth the wavelength 2 wires that are half the wavelength Large Loop: Equal to wavelength Short Loop: Equal to one-tenth the wavelength Advantages Impedance matches well with transmission line impedance Folded Dipole maximizes signal strength Ease of construction High gain - strong transmission Compact in size Disadvantages Can only work better with a combination Required adjustment and displacement of antenna Low signalto-noise ratio Used only for fixed frequency operations Very high resonance quality factor Power Supply The motors and control system on the rover require electrical power to operate. CRT considered using a power tether extending to the launch vehicle. Providing power through a tether eliminates the need for a power supply onboard the rover, so CRT could reduce the size of the rover and more easily fit it inside the launch vehicle airframe. Using a tether would also ensure the rover only moves 5 ft from the launch vehicle. However, the primary disadvantage of a tether is the potential to become entangled with the environment, which could affect the direction of the rover and potentially prevent it from reaching the required 5-ft distance. Another disadvantage CRT considered was the space required on board the launch vehicle to hold the tether. Because of these drawbacks, CRT has decided to instead use a battery on board the rover. While this approach adds size and weight to the rover, it is unlikely to cause the system to fail mechanically. The battery is stored either in or on the chassis of the rover, depending on the dimensions of the battery selected. The exact battery used will depend on the requirements of the selected motors and control board. A major consequence of this choice is that the battery takes up a significant amount of space on the rover. This either reduces the amount of space that can be allotted to other components or increases the overall size of the rover. Additionally, the battery is likely to have significant mass, so its position will change the balance of the chassis. CRT may be able to address this issue by placing the battery on the bottom of the chassis to avoid elevating the center of mass of the rover and therefore destabilizing the chassis. 51

53 5.3 Technical Challenges Table 13: Deployable Rover System Technical Challenges Challenge The rover must fit inside the airframe. The chassis joining the two side-by-side wheels will spin out of position if the torque from the motors fails to spin the wheels. Solar panels must be stored and deployed from the rover chassis. The motors and control system on the rover must receive electrical power. The rover must move through 5 ft of unpredictable terrain. The wheel must not twist off the axle while the rover is in motion. The rover must be constrained within the launch vehicle prior to its intentional deployment. The rover must exit the launch vehicle. The electronics on the rover must be protected from the elements. The rover must be remotely triggered. Solution The rover has a narrow chassis, with two wheels side-by-side to maximize the usable space inside the airframe. The rover has a stabilizing wheel extended slightly beyond the wheel diameter to stop the chassis from spinning. The solar panels are mounted on the exterior surface of the chassis and a small motor actuates them apart. A battery is placed on board the rover chassis. The rover has two large wheels fit with treads and has the ability to avoid possible obstacles. The axle has non-circular cross sections at the ends, and the wheels have the same shaped holes. The rover rests inside a housing, closed at both ends by bulkheads. A linear actuator pushes the rover out of the launch vehicle section after landing. A waterproof covering protects the internal components of the rover. Wireless radio communication is used to send a start signal. 52

54 6 Testing Plan 6.1 Independent Testing and Validation (INTEV) INTEV Mission Requirements 1. Verify that all components on board the launch vehicle are capable of completing the mission. 2. Develop appropriate testing procedures that produce valuable data through reliable and repeatable testing of components. 3. Build long-term, general-use testing devices to validate models and predictions. INTEV Summary No engineering project could succeed without some level of testing and validation. While software models and simulations can serve to aid in the verification process, such models must still be verified at some level by physical tests. Most established engineering companies devote countless time and resources towards testing and verification efforts, as doing so reduces the possibility of anomalies further down the production timeline. CRT is emulating this environment found so commonly in industry through INTEV. Though some aspects of this year s Student Launch competition involve elements external to the launch vehicle, many of them require emulation of various flight conditions in order to more accurately evaluate their success. By designing testing devices and developing proper procedures, CRT is enabled to evaluate many designs swiftly and thoroughly, providing valuable insight into the performance of each. Repeatable testing is useful not only for vetting design concepts, but also for ensuring overall system reliability and dependability. Launches require extensive logistical, financial, and technical effort in addition to presenting great risk to the launch vehicle. Untested components may also present a greater safety risk, especially under launch conditions. Thus, it is essential to ensure systems reliability and safety before launch to save time, money, and resources. INTEV is responsible for the objectives outlined in this section. Ultimately, INTEV works to establish accurate, reliable tests and testing procedures to better validate each launch vehicle subsystem and its components. 6.2 Testing Plan Standard flight tests will be necessary for all components on the launch vehicle. A custom built centrifuge enables CRT to simulate launch vehicle acceleration, while a shock test rig simulates large impulses of force, such as those experienced when impacting terrain. However, more complex components may require specific, more comprehensive testing. As CRT determines which systems to develop and specific challenges to pursue, testing criteria will be created to properly evaluate these such designs. Effective and unambiguous communication is required to successfully coordinate every aspect of all test procedures. INTEV is responsible for the development of such a procedure as well as the creation of necessary testing equipment and devices. In the figure below, the standard template for testing procedures is given. 53

55 Figure 26: Test Procedure Template 54

56 7 Project Plan 7.1 Development Schedule/Timeline Task Table 14: Expected Development Schedule Competition Timeline Expected Date of Completion Proposal 9/20/17 Subscale Launch 10/18/17 PDR 11/3/17 CDR 1/12/18 First Full Scale Launch 2/25/18 FRR 3/5/18 Competition 4/4/18 PLAR 4/27/18 Task Start Date End Date Brainstorm and design the airframe. Research altimeters, air brake, and parachute releases Airframe Subteam 9/1/17 9/30/17 Build the subscale aiframe and continue research 9/30/17 10/28/17 Have select members become L1 certified 10/15/17 11/15/17 Design the full scale airframe 11/1/17 12/15/17 Construct the full scale airframe 12/15/17 2/25/18 Make adjustments based on launch 2/25/18 3/18/18 Perform additional full scale launch if needed 3/18/18 3/19/18 Deployable Rover System Brainstorm 9/1/17 9/30/17 Select preliminary design and CAD 9/13/17 10/7/17 Construct subscale prototype 10/8/17 10/28/17 Revise design 10/29/17 1/10/18 Construct full scale design 1/11/18 1/24/18 Test systems 1/24/18 2/23/18 55

57 Troubleshoot and make adjustments 2/22/18 3/28/18 Electrical & Software Subteam Develop high-level integration plans 9/1/17 10/1/17 Design, analyze, and refine all schematic designs 10/1/17 10/30/17 Build initial prototypes and order PCBs 10/30/17 11/17/17 Assemble and test individual PCBs 11/17/17 11/26/17 Integrate assembled modules; revise if needed 11/26/17 12/9/17 Complete system level integration and testing between all modules 12/9/17 1/15/18 Complete integration with mechanical components 1/15/18 2/3/18 Perform full scale integration testing 2/3/18 2/28/18 Design final revision and create backups 3/1/18 3/22/18 Communications Find issues within previously collected tracking data 9/1/17 9/14/17 Improve functionality of existing communications system 9/14/17 11/1/17 Determine viability of in-house tracking radios 10/25/17 11/22/17 Redesign ground station software 10/25/17 12/5/17 Redesign housing for TRACER module 1/15/18 1/27/18 Test full system functionality 1/27/18 2/25/18 Independent Test and Validation Verify functionality of motor test system 9/10/17 9/17/17 Complete the centrifuge electrical system 9/17/17 11/18/17 Design and develop shock test system 8/28/17 12/2/17 Develop and build subteam test rig 1 9/17/17 12/2/17 Develop and build subteam test rig 2 9/17/17 12/2/17 Research and implement weather balloon system 1/14/18 4/14/18 The above schedule is summarized on the next page in a Gantt chart 56

58 Figure 1: Gantt chart 7.2 Budget CRT has a projected budget for the launch vehicle of approximately $21,110, as shown in the breakdown in Table 15. Efforts are being made to secure additional sponsorship and funding throughout the competition cycle. Table 15: Subteam Breakdown and Projected Expenses Airframe $3,340 Fiberglass Raw Sheet Stock $700 Nosecone $150 Motor Casing $350 L Motors $720 Subscale Motor $70 Level 1 Certification $300 Research $700 Miscellaneous $350 Communications $ mW BeeLine Transmitters $ mW GPS Module $259 Arduino Uno $25 57