Notre Dame Rocketry Team. Flight Readiness Review March 8, :00 PM CST

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Deborah Owens
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1 Notre Dame Rocketry Team Flight Readiness Review March 8, :00 PM CST

2 Contents Overview Vehicle Design Recovery Subsystem Experimental Payloads Deployable Rover Payload Air Braking System Safety and Testing

3 Mission Statement & Requirements Design and build a launch vehicle that: Reaches 5,280 feet Carries 2 experimental payloads Deployable Rover Payload Air Braking System Deploys a rover after landing that travels at least 5 feet away from the vehicle Is reusable on the same day as launch

4 Contents Overview Vehicle Design Recovery Subsystem Experimental Payloads Deployable Rover Payload Air Braking System Safety and Testing

5 Launch Vehicle Summary

6 Finalized Vehicle Dimensions Property Dimension Length (in) 136 Fore Outer Diameter (in) 7.74 Fore Inner Diameter (in) 7.50 Aft Outer Diameter (in) 5.54 Aft Inner Diameter (in) 5.38 Number of Fins 4 Fin Span (in) 7.0 Loaded Weight (oz) 724 Weight without Motor or Ballast (oz) 569

7 Final Vehicle Assembly

8 Launch Vehicle Sections and Components

9 Vehicle Exploded View

10 Design Changes Material Changes due to vendor complications Carbon Fiber Body Tubes and Couplers Phenolic Fiberglass bulkheads and centering rings Birch Plywood Carbon Fiber Fins Birch Plywood Resulting Mass Changes New materials decreased mass without motor from 622 oz to 569 oz 25 oz of ballast was added to decrease apogee to acceptable range Necessary Changes for Stability Fin height outside of body tube decreased from 7.2 in to 6 in

11 Design Changes (cont.) Transition Section coupling length to minimum of 0.75 calipers on forward non-separating, section and minimum 1.0 caliper on aft, separating section

12 Final Transition Section Design Connects fiberglass 7.74 in diameter Rover Payload Bay and phenolic 5.54 in diameter main body tube Extends 6 in in both directions (>1 caliper in aft direction and 0.75 caliper in forward direction)

Final Recovery Integration Located in the middle section of the rocket CRAM screws into custom 3D printed mount Mount is epoxied and screwed into rocket body Eye

13 Final Recovery Integration Located in the middle section of the rocket CRAM screws into custom 3D printed mount Mount is epoxied and screwed into rocket body Eye bolts through bulkheads attached to CRAM allow attachment of shock cords and parachutes Shear pins hold sections of the rocket together and are sheared by charges in CRAM

14 Final Fin Design Material: Birch Plywood Height above body: 6 in Integration into fin can through 0.25 in slots using Rocketpoxy Parallelogram shape for greater stability and flutter prevention

15 Final Motor Choice: Cesaroni L-1395-BS Diameter: 2.95 inches Average Thrust: 314 lbf Length: inches Peak Thrust: lbf Total Weight: 9.46 lbs Total Impulse: lbf*s Thrust to Weight: 8.58 Burn Time: 3.51 s

16 Final Motor Mount Design 26.5 in Motor Mount Tube flush with fin can 32.5 in Fin Can Tube Capping Bulkhead 3 Centering Rings API Quick-Change Retention System

17 Final Rail Buttons 12 ft long 1.5 in wide rail Airfoil rail buttons Mounted 1.3 in from fin can at 0.5 in and in from rear of vehicle

18 Other Key Design Features Deployable Rover Payload Upon landing, deploy a rover that will travel a distance of five feet from the vehicle and deploy solar panels Air Braking System Air Braking Tabs will deploy based on an algorithm to make projected apogee as close to 5280 ft. as possible Flight Plan Ignition, burnout, ABP activated, apogee reached/drogue deployment, main deployment, landing, deployable rover activation, recovery

19 Simulations and Stability Stability Margin OpenRocket prediction: 2.86 body tube diameters Rocksim prediction: 3.01 body tube diameters

20 Simulations and Stability Velocity off the rod: 63.5 ft/s Maximum Acceleration: 245 ft/s^2 Apogee Predictions: 5 mph winds: 5404 ft. 10 mph winds: 5372 ft. 15 mph winds: 5333 ft. 20 mph winds: 5268 ft. CD Averages During engine burn: 0.28 After burnout: 0.30

21 Mass Statement Component Mass (oz) Nose Cone 31.2 Rover Payload Section Recovery Section ABP Section Fin Can Motor 117 Total Weight (46.64 lbs)

22 Full Scale Test Flight 136 inches long 7.74 inch fore outer diameter, 5.54 aft outer diameter Cesaroni L1115 Launch successful, recovery malfunction Main deployment at apogee Drift of ~0.9 miles Nose cone fell from 5765 feet

23 Full Scale Launch Results Apogee predictions off by approximately 20 feet. Second test launch day scheduled for March 17th This will test the Air Braking System and Deployable Rover Payload Will also test the rocket on the competition motor: Cesaroni L1395

24 Status of Requirement Verification Completed OpenRocket/Rocksim simulations Subscale launch on December 2nd, 2017 Altimeters tested in subscale flight Vehicle design and motor choice Recovery system design and sizing Stability of vehicle confirmed Full scale launch March 3rd, 2018 Component tests, shake tests In Progress Continued testing of recovery system Not Completed Second full scale test flight on March 17th, 2018 Air Braking System verified to decrease apogee to 5280 feet

25 Vehicle Test Plans and Procedures Completed Shake and impact tests of payload and body tube integration Initial black powder testing In Progress Refined black powder testing Not Completed Second full scale test flight on March 17th, 2018

26 Contents Overview Vehicle Design Recovery Subsystem Experimental Payloads Deployable Rover Payload Air Braking System Safety and Testing

27 Parachute Sizes and Descent Rates: Drogue Parachute: 24 Helical Nylon Deployed at Apogee Descent Velocity: 78 ft/s Rocket Weight vs Descent Velocity

28 Parachute Sizes and Descent Rates: Main Parachute: 144 Helical Nylon Deployed at 650 ft Descent Velocity: 13 ft/s Rocket Weight vs Descent Velocity

29 Mission performance predictions Kinetic Energy (ft-lbf) Flight phase Velocity (ft/s) Total rocket (723.5 oz) Fin can (321.7 oz) Motor burnout ,000 94,600 Apogee/droge deployment Main deployment Landing

Recovery System Tests Direct E-Match Tests LED Altimeter Simulation Testing E-Match Altimeter Simulation Trial Type Number of Trial Attempts Number

30 Recovery System Tests Direct E-Match Tests LED Altimeter Simulation Testing E-Match Altimeter Simulation Trial Type Number of Trial Attempts Number of Trial Successes Battery directly to e-match Altimeter simulation to LED Altimeter simulation to e-match 9 10 LED Altimeter Test Setup

31 Recovery System Tests, cont. Altimeter Arming Procedure Ensures proper connection of E-Matches to altimeter Altimeter Shake Test Black Powder/Shear Pin 3 tests before launch Black Powder Testing Setup

32 Recovery Subsystem Overview

3D-printed coupler Secured by three screws that go through

33 Recovery Subsystem Overview CRAM is inserted into body tube using screw to lock mechanism Twists into body tube using a 3D-printed coupler Secured by three screws that go through body tube, coupler, and CRAM to prevent untwisting during flight

34 Recovery Subsystem Dimensions Main Parachute: 12 ft diameter with a bleed hole Drogue Parachute: 2 ft diameter with a bleed hole Shock cords (2x): 42 ft length, 9/16 width CRAM: 4.98 diameter, 8.5 length

35 Integration Retaining screws secure CRAM to coupler and body tube Eyebolts are used to connect the CRAM to the rest of the vehicle

36 Contents Overview Vehicle Design Recovery Subsystem Experimental Payloads Deployable Rover Payload Air Braking System Safety and Testing

37 Deployable Rover: Summary Objective Remotely deploy rover upon landing Unfold two sets of solar panels once cleared from the rocket Terms of Success Autonomously drives five feet away from the rocket Solar panels unfold and provide measurable power to the rover The rover will be reusable within the same launch day

38 Deployable Rover: Design Overview Located directly below the nose cone Remotely deploy via a radio ground station and two black powder ejection charges The rover is able to drive in an inverted orientation Body of the rover is machined HDPE with 3D printed mounts for components Detects objects via LiDAR sensor Set of folded solar panels driven by a servo motor.

39 Solar Panels Set of folding solar panels mounted to center of rover and 2 extending rods, driven by a servo motor. Extends upon exit from body tube to triple surface area of solar array. Electrical functionality is verified by a resistor placed on the board powered only by the solar cells.

receiving signal now on rover itself Rover receives signal to

40 Deployment System Signal sent to initiate nose cone ejection 1 g black powder above and below rover (redundant) Electronics receiving signal now on rover itself Rover receives signal to retract securing racks Drives out from tracks in body tube to spring-loaded ramp

41 Wheels and Motors Customized 3D printed hubs Goolsky FY-CL01 tires Lego Power functions XL motors provide more torque 220 rpm unloaded lbf in at 600mA

Electronics - Sensors LoRa Long Range Low Power Wireless communications Multi-stage testing Computer to computer Computer to PIC GPS Used to track position throughout flight and deployment Tested

42 Electronics - Sensors LoRa Long Range Low Power Wireless communications Multi-stage testing Computer to computer Computer to PIC GPS Used to track position throughout flight and deployment Tested with Salae logic analyzer Verify cold start time Ensure correct GPS coordinates Bluetooth Used to triangulate position with respect to each section of the rocket Tested using NRF connect to ensure that the drop off is adequate to calculate distance Altimeter/LiDAR/Gyroscope Used to gather flight data and for object avoidance Created I2C test code and printed output to a terminal

43 Electronics-Powertrain Motor Drivers Uses same chip as normal lego XL drivers Tested with modified lego motors Battery circuits Two 3.4V nominal batteries Circuits using linear regulators switch to 3.3V and 5V for use by the other boards

44 Rover Assembly Step 1: Creating Parts Mill body, cut racks, and 3D print mounts Drill and tap holes for mounts on body Step 2: Structural Assembly Attach mounts and components within with nylon screws Attach wheels with lego connectors and reinforce with epoxy. Attach wires for electronic components and secured close to body with zip-ties.

45 Rover Integration with Rocket Involved epoxying the tracks (with hinges for ramps) and mounting blocks with a milled alignment tool. Connected to the transition section with RocketPoxy

Deployment System Assembly Three bulkheads were initially milled. 2 PVC tubes were epoxied to the base bulkhead, and the other two bulkheads were epoxied into the nose cone.

46 Deployment System Assembly Three bulkheads were initially milled. 2 PVC tubes were epoxied to the base bulkhead, and the other two bulkheads were epoxied into the nose cone. Holes were milled in the middle bulkhead to allow the PVC tubes to pass through. 3D printed rover mounts were epoxied to the body tube using the rover rack extension to ensure precise placement.

47 Rover System Testing Shake Test - Rover must be fixed along the securing mounts inside the launch vehicle to prevent motion in all directions Object Avoidance and Rocket Detection Test

48 Black Powder Ejection Testing Optimize the number of shear pins and black powder 8 shear pins 1 gram of black powder per pipe

49 NASA Requirements Requirement Requirement will be met by Verification Teams will design a custom rover that will deploy from the internal structure of the launch vehicle The rover is built from a combination of custom milled HDPE, 3D printed components and commercially available parts. The rover is secured directly below the nose cone and is deployed using a radio controlled ground station. At landing, the team will remotely activate a trigger to deploy the rover from the rocket A LoRa module is used for wireless communication to the rover. This module will interface with a laptop base station to initiate the deployment sequence upon a safe landing After deployment, the rover will autonomously move at least 5ft (in any direction) from the launch vehicle. Bluetooth chips are placed throughout the body of the rocket to provide triangulation to the rover. Once the rover has reached its final destination, it will deploy a set of foldable solar cell panels When the rover registers the safe distance from the rocket a servomotor drives the solar array out. The array will triple in surface area due to the folds. A fully constructed rover payload was present for the full scale launch Securing system tested with shake test and full scale launch The LoRa module was tested without ejection charges Ground testing was performed to optimize the amount of black powder used Full scale launch to test the entire system will be performed in late March Isolated bluetooth tests were performed prior to construction Ground tests were performed to ensure the placement of the chips allowed for accurate triangulation Full scale flight test performed in late March Prior to the full scale test flight the deployment sequence was tested and confirmed using a dummy array. The full scale flight tested the entire rover sequence including the solar panels.

50 Team Requirements Requirement Requirement will be met by The nose cone will be deployed via black powder charges allowing the rover to drive out of the rocket Two PVC pipes mounted at the rear of the payload will contain two grams of black powder (one gram in each pipe). The base station initiates the deployment sequence that ignites e-matches and sets of the ejection charges. Shunt pins are in place to prevent misfire before the rocket is loaded onto the pad Oversized wheels provide clearance in both orientations. The electronics are configured for driving in either orientation. Upon landing, the rover will be capable of driving in an inverted position Verification Ground tests were performed to optimize the number of shear pins securing the nose cone and the amount of black powder used. Full Scale Launch verified the deployment - to be done in late March A redundant system is in place to ensure the ignition of the ejection charges. The rover was tested in both orientations and successfully avoided objects and detected the rocket Rover successfully drove and maneuvered on rough terrain similar to the expected competition terrain

51 Contents Overview Vehicle Design Recovery Subsystem Experimental Payloads Deployable Rover Payload Air Braking System Safety and Testing

52 Air Braking System: Overview Four variable extension drag tabs will induce an additional, controllable drag force on the rocket The drag tabs will be controlled by a crank-slider mechanism, driven by a central shaft connected to two servo motors The servo motors will be controlled by a microcontroller running a control code Separate power sources for the servos and microcontroller The control code uses a combination of barometer and accelerometer data along with PID control to determine tab extension

53 Air Braking System: Overview

54 Air Braking System: Drag Tabs Four variable extension drag tabs cut via CNC routing Made of 0.25 in. thick UHMW Tapped holes for connection with M3 bolts Tabs machined smaller than designed to allow for tolerances in the fit Extra volume removed from a top corner of each tab to reduce interference with the tie rods

55 Air Braking System: Mechanism Crank-slider design with central, driven shaft When assembled, the tie rods interfered with the tabs at full retraction at the corners Material was milled from these corners, allowing full retraction of the tabs

Air Braking System: Mechanism Tie rods connect the crosspiece to the tabs The anticipated spacers between each of the tie ends were not necessary to achieve desired length Tie ends were milled

56 Air Braking System: Mechanism Tie rods connect the crosspiece to the tabs The anticipated spacers between each of the tie ends were not necessary to achieve desired length Tie ends were milled to length and thread locked on a threaded rod. Crosspiece that is driven by a central shaft Piece cut from UHMW Tapped holes for connection with M3 bolts Broached keyhole to transmit shaft torque

3 V Operating Voltage 32 KB SRAM 48 MHz Clock Speed Adafruit Lithium Ion

57 Air Braking System: Electronics Arduino MKR Zero Processes sensor data in-flight Controls tab movements Built-in SD card reader 3.3 V Operating Voltage 32 KB SRAM 48 MHz Clock Speed Adafruit Lithium Ion Battery Powers Arduino -- more than enough battery life 2000 mah capacity 3.7 V Nominal Voltage

4 V operating voltage Combine for a maximum torque of 1120 oz-in Two 7.

58 Air Braking System: Electronics Two Power HD 1235 servo motors actuate the system 7.4 V operating voltage Combine for a maximum torque of 1120 oz-in Two 7.4 V Tenergy lithium-ion batteries wired in parallel are used to power the servo motors 2600 mah capacity Measured 8.4 V at full charge

Air Braking System: Electronics Three molex connectors soldered to the printed circuit board One floating molex connector to add removability to switch No

59 Air Braking System: Electronics Three molex connectors soldered to the printed circuit board One floating molex connector to add removability to switch No on-board voltage division necessary due to separate power supplies Use of shrink wrap, electrical tape, and hot glue to prevent shorts, increase connection strength

Air Braking System: Electronics Two primary flight sensors:

sufficient range and precision for the flight environment

flight progress P3 R25W Potentiometer attached to the servo

60 Air Braking System: Electronics Two primary flight sensors: ADXL 345 accelerometer and BMP 280 barometer; both have sufficient range and precision for the flight environment Both sensors are used to calculate rocket velocity, track flight progress P3 R25W Potentiometer attached to the servo gearbox allows the control code to monitor if the mechanism has jammed

61 Air Braking System: Control Code Before launch, algorithm toggles between armed and disarmed states with an onboard button The drag control algorithm activates after motor burnout Velocity is calculated using barometer data before burnout, then accelerometer data after burnout The microprocessor compares the rocket s velocity to a pre-calculated ideal velocity at the current altitude This error information is fed to a PID controller to command the servo motor which controls tab extension until apogee An onboard potentiometer allows the code to monitor gearbox jams

sequence Each deck is separated from the next by plastic spacers on the threaded rods Four

62 Air Braking System: Integration The electronic components are secured to four HDPE decks Four steel threaded rods hold the system together by connecting the integration decks in sequence Each deck is separated from the next by plastic spacers on the threaded rods Four vehicle integration rods run through the system, with lock nuts to secure system in the fin can

63 Air Braking System: Testing and Verification Mechanism Ground Testing Integration Ground Testing Verified that the servo motors functioned properly and were controllable Power System Ground Testing Performed shake test to determine vibrational integrity of system Servo Motor Ground Testing Verified that drag tabs extended when central shaft turned No jams in the motion Verified that batteries functioned properly Determined loading on the batteries when operating the servo motors PCB Ground Testing Tested connections on PCB

64 Air Braking System: Testing and Verification Sensor Ground Testing Determined noise levels in sensors Control Code Ground Testing Tested response of the system to a simulated flight Tested response of the system to a jammed mechanism Full Scale Flight Test Collect flight and system performance data Determine the effectiveness of the system Improve the system as needed

65 Contents Overview Vehicle Design Recovery Subsystem Experimental Payloads Deployable Rover Payload Air Braking System Safety and Testing

66 Safety & Testing Safety is a live document, always in flux in order to be able to accomodate and account for any and all failures Safety is essential to mitigate risk of critical accidents to team members, general audience, and the launch itself. Changes since CDR: Vast elaboration on FMEA tables for the Vehicle section and Recovery Payload. Potential hazards were added to the launch checklists in order to emphasize safety at the most critical moments before, during, and after the launch

67 Safety & Testing A detailed pre-launch checklist serves as a functional guide for the final assembly process of the rocket. Possible hazards have been identified in launch procedures to help mitigate risks even further. A repeatable launch procedure, with an emphasis on hazardous steps and what to do in case of an emergency, is convenient and beneficial when minimizing risk of failure at the launch site. Post-launch procedure allow for a safe retrieval of the rocket without damaging or severely altering the environment

68 Environmental Concerns It is critical to consider environmental concerns associated with a launch. Environmental hazards that might affect the rocket fall into three categories with some overlap 1. Vehicle integrity hazards 2. Avionics integrity hazards 3. Vehicle behavior hazards Hazards will be mitigated by performing launch when environmental parameters are within acceptable bounds

69 Environmental Concerns Conversely, the rocket can affect its environment negatively, this too must be mitigated Hazards to environment fall within two basic categories 1. Pollution Contamination of groundwater Atmospheric contamination 2. Harm to flora and fauna Fires due to launch Unexpected disturbance of animal habitats and ecosystems during course of launch

70 Failure Mode Analysis Potential hazards and failure modes for vehicle were analyzed through FMEA table. Classified through Risk Assessment Codes (RAC) Technical failure modes were divided into six categories Proposed mitigations and controls for each risk

71 Personnel Safety: General Every member s safety is of utmost importance Safety factors are considered from assembly to launch We will prioritize prevention over intervention Basic precautions: Appropriate safety gear will be worn at all times Only trained members of the team will operate hazardous equipment Safe distances will be kept from all explosives and dangerous devices Appropriate levels of caution will be maintained

72 Personnel Safety: Chemical Exposure to hazardous substances Different substances are dangerous on different timescales Ammonium Perchlorate Immediately rinse with water Handle with gloves Lead Wash hands after soldering Avoid eating/drinking while soldering Fumes Ensure adequate ventilation Battery Acid Ensure that batteries are properly maintained and operated Flush the affected area with either water or sodium bicarbonate depending on the acid Epoxy Immediately rinse area with soap and water

73 Questions?

FLIGHT READINESS REVIEW TEAM OPTICS

FLIGHT READINESS REVIEW TEAM OPTICS LAUNCH VEHICLE AND PAYLOAD DESIGN AND DIMENSIONS Vehicle Diameter 4 Upper Airframe Length 40 Lower Airframe Length 46 Coupler Band Length 1.5 Coupler Length 12 Nose