Figure 1 - Members of CRT at Competition

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2 Table of Contents 1 Team Overview Launch Vehicle Performance Motor Payload Enclosure Mechanism Vehicle Dimensions Apogee Vehicle Summary Flight Performance Performance of Tracking Electronics AGSE Performance Overview Payload Manipulation (PM) Payload Enclosure Mechanism (PEM) Launch Pad (LP) Igniter System (IGS) AGSE Electrical Budget and Outreach Educational Engagement Budget Overview Conclusion Lessons Learned Summary of Overall Experience

3 1 Team Overview The Cornell Rocketry Team (CRT) is comprised of 33 members, coming from various majors and all school years. This year, the team was a MAV Centennial Challenge participant. The team has one mentor, Dan Sheerer, and one faculty advisor, Daniel Selva. Figure 1 - Members of CRT at Competition 2 Launch Vehicle Performance 2.1 Motor A Cesaroni K740 C-Star motor was flown for the competition flight in Huntsville, Alabama. The motor has a total impulse of 1854 Ns and an average thrust of N, resulting in a thrust-to-weight ratio of Payload Enclosure Mechanism CRT participated in the Maxi-Mav Centennial Challenge, and the sample payload was flown inside the Payload Enclosure Mechanism (PEM) during the competition flight. The PEM is located in the top section of the launch vehicle, and has an entirely original design developed entirely over the course of the competition. To accept the payload, the design of the PEM incorporates a hinged door that is locked shut by a side-release buckle. The payload is retained by a funnel inside the PEM and locked in place by torsion springs inside the funnel. The funnel system was 3D printed, incorporating removable spring boxes for easy payload removal after flight. The buckle system was modified from standard side-release buckles in order to allow for the door s curved path of approach when closing. The female end of the buckle was also 3D printed. The success of these components during launch demonstrates that these original designs could be effective in wider-scale use. 2

4 Figure 2 - PEM After Retrieval (Left), Before Opening Door (Middle), then PEM After Opening Door (Right) As shown in Figure 2, the door remained locked during flight, and the payload remained retained in the funnel. All internal PEM components remained mounted as intended. 2.3 Vehicle Dimensions Figure 3 - Launch Vehicle General Dimensions The airframe of the launch vehicle is made from 3.98 in diameter, thin-walled fiberglass tubing. All bulkheads, centering rings, and fins are cut from 3/32 in thick fiberglass. The launch vehicle recovery electronics are mounted on a 3D printed avionics sled located in the Avionics Bay, and the tracking electronics are mounted onto acrylic sleds inside the nosecone. 3

5 2.4 Apogee A Perfectflite StratoLogger CF altimeter was used as the official scoring altimeter, and a Perfectflite minialt/wb altimeter was included for redundancy. The apogee recorded by the scoring altimeter was 5,182 ft. The redundant altimeter recorded an apogee of 5,122 ft. 2.5 Vehicle Summary Figure 4 - Space Jam The launch vehicle is divided into three sections that are separated during flight. The forward section includes the nosecone, which houses the vehicle tracking electronics, and the PEM. The middle section includes the main parachute tube and Avionics Bay. The Avionics Bay is constructed from an 8 in section of fiberglass coupler, and it is secured to the main parachute tube by four 8-32 machine screws. It also houses a combination of aluminum blocks and a steel disk which were used as ballast mass for the competition flight. The aft section is the booster, which includes the motor, fin can, and motor retention system, and it also holds the drogue parachute. All sections are tethered together by 9/16 in tubular Nylon. To land within the launch field at a safe descent velocity, the launch vehicle uses a dual-deployment recovery system. The drogue parachute, deployed at apogee, is an 18 in diameter octagonal Top Flight parachute. The main parachute is a 60 in toroidal Iris Ultra parachute, which was expected to be deployed at an altitude of 700 ft. High wind conditions and prior approval from NASA caused the Cornell Rocketry Team to change the altitude at which the main parachute was deployed to 500 ft. The parachutes are deployed using redundant 2 gram black powder charges triggered by altimeters in the Avionics Bay. Two tests flights were performed before the final competition flight. The first test flight demonstrated the structural integrity of the airframe and motor retention system, and that the recovery system could be deployed successfully. A second test flight was flown with an updated ballast configuration to more closely achieve the target altitude. In its final ballasted configuration, the launch vehicle weighs 18.5 lbs and has a stability margin of 3.22 calibers. 4

6 2.6 Flight Performance A flight set-up procedure was followed to prepare the launch vehicle for flight. While conducting a safety check of the recovery electronics, an anomaly was discovered with an onboard Perfectflite StratoLogger SL100 altimeter. Following the completion of its startup sequence, the altimeter would continuously emit two beeps indicating continuity on its main ejection charge terminals, despite no e- matches being wired to the Avionics Bay. Troubleshooting the altimeter did not correct the issue, so it was determined that the altimeter was not suitable for flight. CRT would like to thank the Northview Engineering SL Team for allowing the team to borrow a Perfectflite minialt/wd altimeter to use as a replacement altimeter for competition. Figure 5 - Vehicle Ascent Figure 6 - Upon Recovery with Main Parachute Deployed The launch vehicle was flown successfully, achieving an official altitude of 5,182 ft. The drogue parachute deployed at apogee and the main parachute deployed at 500 ft. Due to high winds on the day of launch, CRT obtained permission from Ian Bryant to adjust the parachute deployment altitudes from 700 ft and 500 ft to 500 ft and 400 ft respectively. This was done to mitigate the risk of the launch vehicle drifting off the launch field due to the higher than expected winds. While the Perfectflite Stratologger CF altimeter used for official scoring functioned properly on launch day, CRT was not able to download flight data from the altimeter after the team had arrived back to Ithaca, NY. The launch vehicle was confirmed to have a landing kinetic energy below 75 ft-lbs for any 5

7 individual section during its first full-scale test flight. Since the main parachute deployed fully at competition as it did during the test flight, the launch vehicle is expected to have landed at a satisfactory descent velocity. As a result of the events during launch day, CRT will include adding at least one spare altimeter to the launch packing list as a hazard mitigation. 2.7 Performance of Tracking Electronics The tracking electronics consisted of three independent systems: one simple radio beacon (SRB), one GPS radio beacon (GRB), and one custom-built tracking electronics module (TEM). The data from the two beacons was received using a Yaesu handheld radio; data from the TEM was received by an XBee radio connected to the ground station laptop. The two beacons (SRB, GRB) operated nominally, with APRS packets containing GPS data regularly received from the GRB, and 2-second-on, 2-second-off pulses received from the SRB. These systems were used successfully to track the launch vehicle throughout its flight and once it landed, though it should be noted that the launch vehicle landed only 0.1 miles from the launch site -- as measured by the GRB -- so serious tracking capabilities were not actually required. As testing results showed, the batteries in both beacons lasted for the entire setup time and flight, and were still fully operational upon recovery. Most of the TEM operated normally, but CRT encountered two anomalies that it had not seen previously. The TEM has the capability to record GPS position (longitude, latitude, and altitude), rotation along three axes, acceleration in three directions, and high definition video from a camera mounted to the inside of the nose cone. It transmits data to the ground station using an XBee radio at a rate of approximately 10Hz, and stores all of the data that it sends locally for backup. The TEM successfully saved and transmitted rotation and acceleration data, and recorded accurate GPS data up to the point of launch. At the point of launch, the GPS did not report accurate data despite maintaining a satellite fix and reporting accurate data up until that point. Neither the logs nor the transmitted data show any GPS coordinate above the height of the launch pad. No previous testing, either in the lab or during test launches, showed this behavior; further investigation is required to determine the cause of this failure. All gyroscope and accelerometer data was successfully captured during this time. The second issue that the TEM faced was that camera data was corrupted and not recoverable. The camera had to be interrupted and restarted at the last minute during the launch; this sequence of events likely caused this failure. 6

8 3 AGSE Performance 3.1 Overview All AGSE systems performed nominally. CRT was able to successfully setup and calibrate the AGSE system within the allocated time, and was ready to perform the AGSE demo at the assigned time slot. Our mass-check was successful, and CRT s total AGSE system mass was lb. Once assembled, the system bounding box was measured as 29 in x 28.5 in x in, which gave the system an overall volume of cubic ft. On the day of the AGSE run, CRT was able to complete the Centennial Challenge task on a single run in only 47.6 seconds. 3.2 Payload Manipulation (PM) Figure 7 - CRT s AGSE Fully Assembled at Competition The Autonomous Retrieval Mechanism (ARM) successfully captured the payload using a 3D printed claw mounted to the end of a linear actuator. This assembly was then rotated with a DC motor to face toward the launch vehicle and the payload was deposited within the Payload Enclosure Mechanism (PEM). All components performed nominally during the AGSE demonstration run and the system successfully received and deposited the payload. The setup configuration of the ARM can be seen below in Figure 8. 7

9 Figure 8 - Initial ARM Setup 3.3 Payload Enclosure Mechanism (PEM) During the AGSE demonstration, the PEM door was pulled closed by a rope system operated by a rotational motor. Prior to closure, the door was held open by an acrylic bracket. Upon payload insertion, a rope to the bracket, wrapping around the motor shaft, pulled the bracket inside the PEM to allow the door to close. Subsequently, a rope to the door, wrapping around the motor shaft, pulled the door completely closed, locking closed a side-release buckle (with male end mounted on the door and female end mounted on the airframe). Upon actuation of the launch vehicle to the vertical, the payload slid inside a funnel below the location of payload insertion. Figure 9 - PEM Door Closed in AGSE 8

10 3.4 Launch Pad (LP) All Launch Pad (LP) systems performed nominally during the AGSE demonstration. After the PEM door closed fully, the winch retracted its cable, leading to a successful rail actuation. The angle of the rail was calibrated during the AGSE setup time using the official competition level, which ensured that the final angle measure would not be affected by differences in instrumentation. As a result, the final rail angle was within the desired plus or minus 0.5 o from 85.0 o. All LP components remained stable throughout its operation, and the system took approximately 5 seconds to complete its operations. 3.5 Igniter System (IGS) Figure 10 - The Angle of the Launch Rail is Judged to be 85.0 o The Igniter System (IGS) performed optimally during the AGSE demonstration. The linear actuator successfully inserted the igniter tube into the mock motor without impacting the mock motor wall. The foam damper component and lithium grease eliminated any potentially hazardous vibrations of the tube assembly and igniter insert during its ascension up the motor. The original success criteria for the IGS were to insert the igniter to the correct distance into the motor, keep the igniter aligned (concentric) with the motor, and complete the igniter insertion in under 18 seconds. In its performance in the AGSE demonstration, the IGS optimally met all criteria for success. In addition, the paper igniter insert, which was designed to be destroyed upon motor ignition to prevent motor over pressurization, was successfully inserted into the mock motor without any damage. This shows that the concept can be safely utilized to insert an igniter into the rocket motor in an actual launch scenario. 9

11 3.6 AGSE Electrical All components of the AGSE Electrical subsystem performed as intended during the AGSE demonstration. All connectors between modules were inserted without issue and no connections were found to have been broken in transit. The CCM (Central Control Module) successfully controlled power to the other modules, only allowing them to power once both the key switch and toggle switch had been moved to their on positions. All ready lights on the CCM also successfully indicated the ready status of the connected modules. The pause switch kept the AGSE procedure paused until the judges indicated that it should start. The PMM (Payload Manipulation Module), IIM (Igniter Insertion Module), and VAM (Vertical Actuation Module), all successfully controlled their portions of the AGSE procedure as detailed in the preceding sections, and the done signal for each portion was properly displayed on the CCM. The GO light indicating that the procedure was complete turned on following the insertion of the igniter, as expected. 4 Budget and Outreach 4.1 Educational Engagement CRT has been engaging the surrounding community with various educational events. In the past, CRT has worked with local middle schools to teach basic scientific and engineering concepts. This tradition has continued this year by organizing different events with students in Ithaca. Those events can be categorized depending on their focus on the engineering behind the rocket or a science subject. This year, CRT has partnered with the Ithaca Sciencenter for volunteering as well as Ithaca Math Circle. Some activities are as follows: Sciencenter Family Nights Family night, which occurred on October 22nd and November 4th, was an event where the members held interactive demonstrations of scientific topics. The format of the event included three different stations in which the students were rotating. Specifically, the three stations were: Station #1: The students decorated a cork, which was then shot out of a bottle by means of an acid base reaction. That way, they learned a basic understanding of acid-base chemistry. Station #2: The students created slime and understood some fundamental characteristics of it. This tended to be a favorite activity among the students. Station #3: The students, with the guidance of a team member, investigated the chemical properties of black bean extract. The general setup of the event was very collaborative and inclusive. Students also brought their parents and volunteers facilitated the different activities. 10

12 Sciencenter Rocketry Day Rocketry Day, which occurred on November 14th, was a day devoted to teaching elementary students some basic engineering concepts. CRT had three different stations in which the students were rotating, in order to get more students engaged. Specifically, the three stations were: Station #1: Students made small rockets using paper and a film canister that was fueled by the chemical reaction between water and Alka-Seltzer. Station #2: Members of CRT demonstrated real life rockets and explained some of the basic principles we use to build and launch them. Station #3: Students made parachutes using plastic bags, a string and a small weight and then let them go from a certain height. Ithaca Math Circle The Ithaca Math Circle is also a new addition to CRT s outreach schedule, in which women from CRT were tutoring middle school girls in math on three Saturdays. There, CRT was helping the students prepare for the American Math Competition by teaching them unfamiliar concepts in a small group format and answering their questions. Moreover, CRT was encouraging the young girls to appreciate the simplicity of math in seemingly complex problems. Society of Hispanic Engineers Science Day At the Cornell Society of Hispanic Engineers Science Day CRT will showcased the launch vehicle, tracking equipment, parachutes as well as motor casings. In a lecture format, they taught the basics of each part s construction and significance at a launch. Activities planned included: Displaying CRT s posters and past rockets, like s Chewbacca Science goodie bags filled with foam colored rockets (+ rocket launchers), planetary pencils, stickers, science fact cards, and more! National Institute of Aerospace s Engineering Design Challenge CRT members act as Subject Matter Experts (SMEs) to review and analyze student designs of the James Webb Space Telescope and associated technologies. Responsibilities include: Review and comment on virtual multimedia poster session via Glogs Watch and comment on accompanying YouTube narration by each team Provide insight and feedback on design proposal/pitch Last year CRT exceeded the direct STEM outreach requirement by reaching out to over 400 students in the area, with 150 of those students being middle school students. This year, CRT has also exceeded this year s requirement of reaching 200 participants, 100 of which are middle school students and educators. A more detailed plan is in Table 1. 11

13 Table 1 - Educational Engagement Schedule Event Date Number of Students Grade 5-9 Sciencenter Family Night 1 10/22/ Sciencenter Family Night 2 11/04/ Rocketry Day 11/14/ Ithaca Math Circle Various dates Watchung Hills Regional High School Engineering Presentation Cornell Society of Hispanic Engineers Science Day 1/8/ /27/ National Institute of Aerospace s Engineering Design Challenge 3/15/2016-3/17/ South Lakes HighSchool Rocketry Club 3/29/ TOTAL Figure 11 - Percentage of NASA Goal Reached 12

14 In order for CRT to perform to the best of CRT s capabilities and engage the maximum number of students, CRT had an evaluation conducted for the events. The feedback that was received by students, parents and supervisors at the partner organizations was very positive on CRT s performance. Specifically, on the Sciencenter Family Nights and Rocketry Day, the students reported to have really enjoyed their time, while also learning some basic science facts. Favorite activities included the slime creation (Family Night) and paper rockets (Rocketry Day). CRT will now take this feedback under consideration when planning activities in order to target the group even better in the future. Overall, CRT is pleased with the outreach program it organized, since it took consistent commitment to host many of these events. CRT hopes to continue existing outreach partnerships and develop new ones in the future to better spread a passion for STEM topics. 4.2 Budget Overview CRT manages a budget of $21,515 with a cost on pad of $5, This year CRT focused on increasing communication with alumni and establishing more relationships with companies and corporate sponsors. With a redesigned promotional packet and new sponsorship strategy that focused on part donations in lieu of direct funding, CRT partnered with several new companies and reduced the overall costs of both prototyping and manufacturing. Furthermore, a more aggressive social media campaign and introduction of a monthly newsletter helped to maintain the healthy relationships and income flow of previous corporate sponsors and alumni. Finally, throughout the year CRT hosted various successful fundraising events and competed in short competitions and challenges that independently raised over $2,000. The combination of all these income sources amounted to $22,298 which covered all material and travel expenses for this year. A breakdown of all these sources of income can be found in Table 2. Table CRT Income Sources of Funding Contribution Cornell University Organizations $15,500 Cornell University $15,000 Cornell Engineering Alumni $500 Association Alumni Donations $700 The Dempsey Family $500 The Shih Family $100 The Hsu Family $100 Corporations $2850 Boeing $2000 Autodesk $300 Chang Bioscience Inc. $250 Global Promo, LLC. $250 General Electric $50 Gifts In Kind $1188 Accion Systems (Chopsaw) $150 13

15 Uline (600 Industrial Latex Gloves) $48 Fruity Chutes Inc. (Product Discounts) $40 Marsa Systems (Product Discounts) $18 BigRedBee, LLC. (Product Discounts) $13 Pololu (Product Discounts) $4 Monster Tool (Tool Donations) $915 Fundraising $2,060 Autodesk Challenge $1,100 Apogee Components Video $300 Competition Barski s Laser Tag Competiton (Fall $ ) Bake Sale (Fall 2015) $103 The Yang Family $50 Bake Sale (Spring 2016) $40 Skate Night $347 Grand Total Funds Received $22,298 The total expenses for the competition amounted to $21,515 with a cost on pad of $5, These expenses represent the total cost of all prototyping and manufacturing materials, new tools and machinery, travel and lodging expenses, and any promotional or outreach costs. Unexpected part failures and broken components shortly before competition led to an approximate $700 increase from the projected total expenses in the FRR. Despite this minor hiccup, CRT managed to reduce costs through a combination of a new centralized ordering form and custom-made analytical software that minimized shipping expenses. Furthermore, CRT received many parts and software at discounted prices due to various newly made corporate partnerships. A breakdown of expenses by subteam can be found in Table 3. Table CRT Expenses Subteam Expenses Airframe $2,887 PEM $286 Payload Manipulation $679 Launch Pad $2,005 AGSE Electrical $1,346 Communications $935 Business Team $13,377 Total Expenses $21,515 As the winner of the 1st place Centennial Challenge award and $25,000, CRT will have a comfortable start in next year s competition. CRT plans to invest a sizable portion of this award into various research projects focused on trying experimental designs, and will also purchase new lab equipment that will streamline the prototyping and manufacturing processes. Overall, the new income will enable CRT to operate more freely that will encourage more creative experimentation and novel design. 14

16 5 Conclusion 5.1 Lessons Learned CRT learned many lessons through its work on all of its sub-teams this year. One of the most evident lessons learned by the Cornell Rocketry Team is that in the future the parachute needs to be placed approximately 2/3rds of the shock cord away from the body of the launch vehicle. Otherwise, when the blast charges are deployed the nosecone has the ability to entangle the shroud lines of the parachute, which will stop the parachute from fully unfurling. If the ground had not been so soft at the launch field, this could have been a critical error, which might have stopped CRT from competing in the NASA Student Launch competition in general. Thus, next year it will be one of the failure modes that the Cornell Rocketry Team will be sure to focus on. In addition, CRT learned that when working with swinging systems, torque must be accounted for. Initially when the Cornell Rocketry Team developed the Autonomous Retrieval Mechanism (ARM) the programming for the system did not take into account the angular momentum that the arm would possess after swinging a full 180 degrees. This issue was dealt with through the use of a proportionalintegral-derivative (PID) controller, which enabled CRT to monitor the velocity of the ARM as it swung to capture the payload and to load the payload into the rocket. In addition, because PID was used, the Cornell Rocketry Team was able to slow down the ARM just prior to stopping its motion, which produced a more smooth output velocity than had CRT only monitored the position of the ARM. Furthermore CRT learned that commercially available touch sensors tend to be approximately wide by in height, which is much too large for many of the small systems that the Cornell Rocketry Team designs and manufactures. This led to the Cornell Rocketry Team swapping to an infrared sensor, which worked much more effectively than expected. Initially CRT had been concerned that an infrared sensor would have problems with the surrounding environment, such as irregularities in the Payload Enclosure Mechanism and the ground, which might interfere with the ARM s ability to consistently work properly. However, as the final design showed, the infrared sensor worked exactly as the Cornell Rocketry Team wanted. Another minor lesson that CRT learned was that in the future the launch rail and blast deflector setup can be modified to take up less volume. This year, CRT designed the launch rail to be extra-long in order to ensure that the launch vehicle was travelling at an optimal speed prior to leaving the launch rail. In the future, CRT can remove a few more inches without changing the safety margins of the launch rail. In addition, the blast deflector was oversized in an attempt to ensure that all of the vital components underneath it including the 12V battery, the winch, and the AGSE electronics would not be burnt when the motor was ignited. By utilizing other blast deflector designs, the Cornell Rocketry Team plans to further reduce the maximum volume of its system. 15

17 This year was an extremely successful year for the Cornell Rocketry Team and many of the systems designed and built this year were based on the mistakes from last year. For example, last year the payload capturing mechanism was a crane. However, the crane required a large amount of volume and was extremely inaccurate. By changing the payload capturing mechanism to a small rotating arm, CRT was able to decrease the volume it utilized and developed a much more robust system. In the future CRT plans on learning from the mistakes it made this year to help it develop an even better system for next year. 5.2 Summary of Overall Experience Overall, CRT had a very valuable and worthwhile experience participating in the NASA Student Launch and Centennial Challenge programs. From the very beginning, CRT has appreciated the opportunity to work with NASA through frequent design reviews. From our proposal, all the way through our FRR, we are grateful for the time and effort NASA has put into working with our team and for the feedback they have provided on our design. Participating in an 8-month design cycle has made our team better prepared to enter the workforce, as we have gained exposure in what it is really like to design a system from start to finish. Traveling to Huntsville and participating in the on-site competition was also a valuable experience for the team. The opportunity to tour Marshall Space Flight Center was an educational experience for the 13 team members who traveled to Huntsville, Alabama. Touring lab spaces and test stands gave our team members a glimpse into what it would look like to work for NASA. Listening to talks about the SLS and about Kjell Lindgren s experiences on the ISS were once in a lifetime opportunities that will not be forgotten. The team felt that our AGSE setup time was used well, and we were able to successfully set up our AGSE, take our volume measurement, and do a few test runs in less than 3 hours. The next morning, we returned at our allocated time and did a few more test runs before our final AGSE judging. As all systems operated nominally, the team was ecstatic. Our team also enjoyed the opportunity to walk around and look at other team s AGSE setups, and watch other teams complete their judging runs. Our team members who were not in Huntsville appreciated the live stream of the AGSE runs, as it allowed them to watch our run back in New York. Our goal for the AGSE portion of the challenge was to have a lightweight, small, and robust system that operated on its first try. We firmly believe that we met this AGSE goal. Our team also appreciated the effort that NAR put into making sure that each rocket was safe to fly. Our LRR was thorough, and the NAR volunteers were beneficial in making sure that our rocket was as safe to fly as possible. We had minor punch-list items that we remedied before the next day. The rocket fair was an exciting experience for the team, as we were able to meet NASA Engineers, employees from Orbital ATK, and other NASA student launch teams. We took advantage of the opportunity, and asked many questions about the other team s launch vehicles and their experiences. We also fielded many questions about our own rocket and AGSE. 16

18 Launch day was also a success. We appreciate the host farm for preparing a great venue for the launch and providing us with a large field for recovery. We really enjoyed watching the other rockets launch, including the middle and high school students. Our vehicle reached an apogee of 5182 ft. Our launch vehicle landed quite close to the pad and showed no signs of damage upon inspection. This result was to be expected, as CRT had successfully completed two full-scale flights with similar results. Our team is very satisfied with the results of our launch day performance. Overall, this was a historic year for CRT. We are very appreciative of all of the hard work that the NASA team has put into running the competition. We are also grateful to be the recipients of the 1st place Centennial Challenge award, as well as the Launch Vehicle Design Award. We would also like to thank Orbital ATK for their generous sponsorship of the competition. CRT looks forward to applying everything we have learned this year as we prepare to compete again next year. The overall experience was a valuable one that we would recommend to other teams across the country. 17