Jordan High School Rocketry Team (JHSRT) A Roll Stabilized Video Platform

Transcription

1 Jordan High School Rocketry Team (JHSRT) A Roll Stabilized Video Platform Post Launch Assessment Review 29 April 2015 Contact Address: C.E. Jordan High School Attn: Dr. Jeffrey LaCosse 6806 Garrett Road Durham, NC 27707

2 Table of Contents 1 Team Name 1.1 Team name and mailing address 1.2 Name of mentor, NAR/TRA number and certification level 2 Motor Used 3 Payload Description 4 Vehicle Dimensions 5 Altitude 6 Vehicle Summary 7 Vehicle Data Analysis 8 Payload Summary 9 Payload Data Analysis 10a Scientific Value (RAD) 10a.1 Payload Objectives 10a.2 Scientific Approach 10a.3 Meaningfulness 10b Scientific Value (ILD) 10b.1 Payload Objectives 10b.2 Scientific Approach 10b.3 Meaningfulness 11 Visual Data 11.1 On the Ground 11.2 In the Video 12 Problems and Lessons 13 Experience 14 Educational Engagement 15 Budget Summary 1

3 1 Team Name The Jordan High School Rocketry Team, or JHSRT, is based at Charles E. Jordan High School (JHS) in Durham, NC. We have also picked up a few students from other Durham County Schools, such as Kestrel Heights Middle School and Middle College High School. JHS is a traditional public high school in the Durham (County) Public Schools system. JHS opened in 1963 and is located in south Durham. It currently has an enrollment of 2,048 students in grades Team name and mailing address The Durham Area Rocketry Team, or DART, can be contacted at: C.E. Jordan High School Attn: Dr. Jeffrey LaCosse 6806 Garrett Road Durham, NC Name of mentor, NAR/TRA number and certification level Dave Morey, NAR #17918 L2, TRA #8115 L2 2

4 2 Motor Used The motor used during flight in Huntsville was an Aerotech K1000T. The thrust curve of the motor can be seen below. The two previous flights of Ursa Major were also flown using a K1000T. 3

5 3 Payload Description The role of the RAD is to detect the roll or spin of a rocket during flight and to counteract any roll inducing torque on the rocket by varying the speed of a motor driven flywheel. The device will be remotely activated (flywheel spun up to half speed) before launch, and then automatically deactivated after the rocket has reached maximum altitude. The desired effect is that the video cameras, in camera pods attached to the rocket, obtain footage that is fixated in one direction to signify a flight with no roll. A panoramic slow roll can also be programmed. This payload was initially developed for the Student Launch last year. The goal this year is to improve the original design and programming in order to maximize its success and efficiency. The two keychain cameras were housed in 3D printed shells on either side of the rocket. Both were turned on at the launch pad and took videos of the flight. They were utilized in determining whether or not the payload had been successful for the videos would be focused on one point during the ascent if there was no spin. The ILD consists of multiple small helium filled balloons tied to fishing line. These balloons were anchored in the nose cone and released along with the main parachute. Visible from a distance, these balloons were intended to aid JHSRT members in locating the rocket after it lands. The inspiration for this payload was from Launch Day at Huntsville last year, when it took the recovery team upwards of 45 minutes to retrieve the rocket, as visibility over the foliage was very low. 4

6 4 Vehicle Dimensions Dimensions: Height Airframe Diameter Fin Span Main Parachute Diameter Drogue Parachute Diameter 89 in in 13.5 in 84 in 24 in Flight Info: Flight Motor Mass (lbs) CG (from top of fin section) (in) Flight 1 K1000T 22.6 lbs 60.6 in Flight 2 K1000T 23.7 lbs 60.6 in Flight 3 K1000T 23.7 lbs 60.6 in 5

7 5 Altitude Huntsville Flight Raven Altimeters Altimeter Data Raven (Main) 4940 Raven (Backup) 4940 The highest recorded GPS altitude was 4990 feet, which matches data from both altimeters. After the rocket landed the wind picked up the parachute and dragged the rocket for just under a mile. Raven plot for the Huntsville flight 6

8 6 Vehicle Summary The vehicle features four carbon fiber and balsa wood composite fins, an airframe made from Blue Tube, a plastic nose cone, and a K1000T motor. Above the motor sits the RAD payload. The ILD payload is situated inside of the nose cone. The two parachutes, one drogue and one main, are stored above the RAD, with a deployment system that uses the drogue chute to minimize drift. In between the drogue and main chutes is the altimeter bay. This is used to gather altitude and velocity well as deploy the parachutes. The plastic nose cone contains a GPS transmitter used to locate the rocket in case it is lost. Finally, there are two keychain cameras mounted to the outside of the rocket to determine the effectiveness of the reaction wheel. 7

9 Finished Rocket Ready for Launch Carbon Fiber Fins Plastic Nose Cone 8

10 Dual deployment recovery system used in the 2016 NASA SLI rocket. Picture taken by Jim Livingston. 9

11 7 Vehicle Data Analysis Flight Sim. Altitude (ft) Raven Main Alt. (ft) Raven Backup Alt. (ft) Mass (kg) Thrust/Weight Ratio Actual Drift (ft) :9.2 ~ : : Path of Ursa Major s second flight at Bayboro, NC 10

12 Path of Ursa Major s third flight at Bragg Farms in Toney, AL during the official Student Launch. The rocket was dragged for just under a mile. Raven plot for Ursa Major s second flight. 11

13 Raven plot for Ursa Major s third flight. Performance vs. Prediction From the data in the flight table, the rocket has performed close to what was predicted for it in the simulations, but not perfect. The rocket always undershot the simulation s predictions. In some cases, this was due to higher wind speeds observed during flight. Recovery System Operation Flight 1 No recovery issues. Flight 2 No recovery issues. Flight 3 No recovery issues. 12

14 8 Payload Summary The primary payload is formally known as the Rocket Alignment Device (RAD). The payload is structured so it can be inserted into a cylindrical tube to be placed in the rocket. At the top of the payload, a new brass reaction wheel is attached to a motor which absorbs or releases angular momentum to the rocket airframe. Below that, the UDB5 UAV Dev Board, Auxiliary Board, Motor and Electronic Batteries are located on one side. The other side, divided by a plank of wood, contains the 3DR Radio Serial Link, the electronic speed control, and the on/off switch. On the outside of the rocket are two mounted keychain cameras. These cameras take video throughout the flight and the goal is for the video from these to stay pointed at the same point. The reaction wheel corrects any roll by either speeding up or slowing down and braking. This angular acceleration corrects the roll, and keeps the rocket s angle in the specified location. A PID algorithm is used to determine how much to accelerate the wheel. The current angular location is calculated from the UDB5 gyro rate sensor by integrating the sensed rotational velocity. Currently, the maximum speed of the reaction wheel is capped at 5200 RPM. The secondary payload is called the Inflatable Location Device, or ILD. This payload is made up of two helium filled balloons attached to a bulkhead that separates the inside of the nose cone from the main parachute bay. This section has a tube that houses the two balloons. Through the flight, the balloons remain in this tube until the main parachute deploys at 576 feet. As the parachute deploys, it pulls off the bulkhead containing the balloons, allowing them to float up. This allows the rocket to be visible over long distances with the help of the helium filled balloons. The ILD did not succeed in helping the team locate the rocket during the Huntsville launch for several reasons. The balloons did not successfully deploy from the nose cone during flight. Even if they had deployed, the rocket was dragged after landing, and the team was not allowed to search for the rocket until it had already travelled a significant distance, which would likely have resulted in damage to the balloons or sufficient leakage for the balloons to stop floating. Furthermore, the rocket was retrieved by the owner of a nearby farm, so the team would not have been able to see the balloons impact on visibility after landing. 13

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16 Note that the ILD designs have been modified to accommodate only two balloons instead of the planned three. 15

17 9 Payload Data Analysis For our Huntsville flight, both payloads were unfortunately not a success. For the first part of the flight, there was little roll, but this was not due to the payload. It is believed that the payload did not function at all. The team is currently investigating the cause of this. The balloon payload did not successfully deploy due to the bulkhead containing it getting jammed in the nose cone. This can be solved with a piston like device. In the future, we hope to improve both payloads to make sure that they work flawlessly every time. The roll is made clear by the cameras mounted on the rocket. The videos from these can be found on the site: jordanrocketry.weebly.com/blog or at our YouTube: goo.gl/qda0uy. All of our flights had defined purposes. Flight 1: The payload was passively spinning to have a control flight for the rocket. The tendency for the rocket to roll clockwise was discovered. Flight 2: This is the first flight with the VESC controller. The payload was being actively controlled with a computer to test whether there was proper communications to the new motor controller. There was more oscillation than intended which may be due to there being wrong variables in the PID algorithm. 16

18 Flight 3: (Huntsville, Alabama) The flight was a test to get the motor to actively control the roll. Due to a programming error, the VESC was commanded to spin the motor at much lower speeds than desired. The error has been duplicated on the ground and diagnosed. It should operate correctly in the next flight. We started the flight with the motor at a slow speed, expecting the natural roll of the rocket to be clockwise. For some reason the rocket spun counterclockwise. For the next flight we will go back to starting the motor at half speed and try not to second guess the roll the rocket will experience. A programming error caused the commanded motor speed to be significantly less than the PID algorithm computed, as seen by the difference between the orange and blue lines in the chart below. The payload was programmed to hold the roll position for two seconds, execute a two second clockwise turn 90 degrees and then hold the position for the rest of the flight. Because we started the motor at too low of a speed, and due to the programming error, roll position control was not achieved. We expect it will work correctly for the next flight. 17

19 The ILD did not deploy so not much data was collected from the Huntsville Flight. The bulkhead and balloons did not come out of the nose cone due to the cater cornering that occurred. In order to prevent this from happening to future flights, we will install a piston to keep the bulkhead from moving. In addition, the shear pins are long enough that they could potentially pop the balloons when deploying, thus we will cut the shear pins before inserting them. 10a Scientific Value (RAD) 10a.1 Payload Objectives The objective of the payload is to be able to control the radial direction the rocket is oriented with virtually no oscillation or overshoot. The onboard video cameras are also expected to be able to record a field of view that is controlled. The payload should not disturb the rocket s flight path or result in yaw pitch coupling (coning motion). Additionally, as this project is a continuation from last year, our hope was that there would be a marketable improvement in the effectiveness of the RAD due to the changes made over the last few months. 18

20 10a.2 Scientific Approach To ensure the integrity of the mission, the initial testing of the payload was completed separately from that of the full scale rocket using a rotational dynamics testing apparatus. By doing so, the programming and constants could be modified as needed without data from the rocket interfering with the payload data. After it was proven, the RAD was tested in launches. First, it was tested with passive movement. Once this succeeded, we improved the programming and flew it again. 10a.3 Meaningfulness The RAD is designed as a method of controlling the roll of our rocket during flight. There are other means of doing so that already exist; however, our team wanted to take a more mechanically oriented approach to this problem. 10b Scientific Value (ILD) 10b.1 Payload Objectives The objective of the ILD payload is to aid in the process of locating and acquiring a rocket after landing by using helium balloons to increase visibility over visual obstructions. The payload should not interfere with the flight in any way. 10b.2 Scientific Approach Testing of the ILD payload requires a multi step process that examines the components individually and then together as a system. The balloons were tested first. They were filled with helium to test the time they would float for and the height of floating. Initially, none of the balloons floated. Each balloon was massed and the lightest ones were selected for the next phase of testing. The lightest balloon were again filled and this time, after tying the knot, the extra end was cut off. The balloons floated for about 30 minutes. Next, the balloons were filled and treated the same way, with the addition of Ultra High Float balloon sealant. With air no longer escaping, the balloon was able to float upwards of two hours. By only testing one 19

21 variable at a time, we were able to develop procedures for preparation of the ILD payload to allow it to function in the most effective way possible. 10b.3 Meaningfulness The ILD payload allows the team to retrieve our rocket quickly and efficiently. Not only does it make the process of locating the rocket after landing far shorter and more convenient for the team, but it should also expedite the process of cleanup by allowing the team to spend significantly less time searching for the rocket. This, in turn, minimizes any environmental concerns tied to litter. 11 Visual Data 11.1 On the Ground All members of the team present at a given flight watch the rocket closely as it is launched, allowing visual data to be observed before checking any data from the altimeter or payload. A list of general observations include: The first flight, despite payload related issues, went very well. The rocket flew very straight and there were no complications. During the rocket s second flight, the balloon payload was observed coming out of the rocket but detaching from its connection to the rocket. There was a bit of arc on the second flight, but this was due to higher wind speeds up to 10 mph upon launch. Huntsville Flight Observations: With wind speeds at 12 mph, our Huntsville flight closely resembled our rocket s second flight, which took place in very similar conditions. Despite some predictable arc into the wind, there were no observable problems during launch or descent. The recovery system deployed perfectly. However, due to the delay between landing and retrieval, the still open parachute caught the wind on the ground and carried the rocket about a mile away into a neighboring field In the Video The video showed at a brief moment the ballast falling out during the second flight. This was solved with a large bolt securing the ballast to the rocket. 20

22 The first flight s video showed a small amount of inherent roll. After the second flight, it was observed that the rocket was rolling back and forth due to the RAD. This was confirmed in the video footage. The third flight s video included roll in what appeared to be a different direction. This was due to different launch conditions at the launch site combined with the RAD not working correctly. Huntsville Flight: Due to RAD payload error, the video captured does not show any significant correction of roll; the rocket flew as though the RAD was not present. In the video, dragging was observed for just under a mile. The fin section stayed on the ground while the main parachute lifted the rest of the rocket over and over again. The paint job suffered, but thankfully, no serious structural damage was sustained. 21

23 12 Problems and Lessons Throughout the project we had several problems: 1. For our first flight, due to the team being unprepared, it took us a great deal of time to prep the rocket. Additionally, the GPS was not communicating with the computer properly, so no data was captured. 2. The team in charge of work on the ILD did not complete testing as fast as the project demanded, and it is likely that we could have seen better results had more testing been completed. This serves as a lesson to the entire team to ensure we stay on top of our individual responsibilities and increase our chances of success. 3. During the launch in Huntsville, the ILD got trapped in the nosecone, and was not able to deploy properly. 4. One of our main programmers was experiencing medical complications for many months of the project. Other students were able to step up to fill the role, but a significant delay in the programming was still observed as a result. 5. The RAD payload was not working properly for the Huntsville flight due to an issue in the programming algorithm. We have identified the issue and it will be corrected for the next flight. Surprisingly enough, the science behind our work is not as much of a problem for the team as one might think. A great deal of our setbacks are a result of personnel error. Team projects such as this come with a high level of individual responsibility and commitment, and when members are not working to their full potential, the entire group is hindered. That being said, compared to the previous year, JHSRT has improved communication between members, as well as overall work ethic and productivity. Last year, one of our reports was turned in late as a result of poor planning and procrastination. Those who have been on the team for two years will agree that improvements have been made, but there is always room for further growth. For example, in the future, it will be important that the team sets hard deadlines for individual tasks that need to be completed. 22

24 13 Experience In the end, the team had a truly enriching experience in Huntsville for Launch Week. After months of hard work, the team was able to see it in action with some of the world s foremost experts on rocketry. While the roll stabilizing device was already built, refining its programming proved to be a difficult task, especially with the new and unfamiliar motor controller. The major challenge became the ILD. Getting the two balloons to fit in the nose cone, stay attached to the rocket and each other, and still float proved to be a worthy challenge. While the RAD didn t work that well and the ILD was unable to deploy at the official launch, the team still feels that both devices were successful in previous and future flights. The launch that was successful overall fills the team with joy and gratitude for having this opportunity. Durham Public Schools and the City of Durham were well represented by our hard work and effort into a national competition. While writing the reports was not exceptionally interesting, it did give the team an insight into how things are really done, and just how time consuming the process is. Launch Week provided an experience we would never have had without it. After our flight in Huntsville, we believe our mission was successful overall. While the RAD did not function and the ILD did not deploy, the flight flew well and came close to the desirable altitude. The RAD s failure was due to human error, we were unable to perfect the programming in time for the flight. The RAD has proven successful in multiple other tests and flights, and thus one failed flight is not going to discourage us too much. The ILD got jammed, so unfortunately, it was unable to be tested. This can be rectified by adding a piston like device into the nose cone to facilitate the detachment of the nose cone bulkhead. We will be flying Ursa Major once again on May 15th, so we hope to continue improving upon our work in the coming weeks. 23

25 14 Educational Engagement During this process of the NASA student launch, we have had two outreach activities. We reached a very large number of people, around a hundred of those being middle or high school students. Due to poor planning and difficulties in organizing the events, we have been unable to organize opportunities to go to Middle Schools to raise interest. In the following year we will be contacting some of the district coordinators in order to plan for events well before the next school year. Given the time to organize these events, as opposed to rushing them, we hope to be able to reach many more in the middle schools around us. We have talked to our fellow students, getting them interested with the program and trying to get them to sign up. So far we ve only gotten a few people to sign up, though several on our current team are freshman and juniors and most plan to continue NASA Student Launch in the following years. 24

26 15 Budget Summary Description Vendor Quantity Unit Cost ($) Rocket Extended Cost ($) Notes 48" long 4" diameter airframe tube Blue Tube " long 4" diameter coupler tube Blue Tube 2.0 Always Ready Rocketry Always Ready Rocketry " Ogive nose cone(3:1) Donated by Dave Morey Plastic Ring/Bulkhead material: Baltic Birch 6mmx12x24 (6) Hobbylinc /4" Plywood Fin End Grain Balsa Leading/Trailing edge half round hardwood Specialized Balsa Wood Specialized Balsa Wood 2.50 sqft ⅜ thick 2 (96in) Fin Carbon Fiber Cloth HobbyKing 2 (2m 2 ) oz 2 yards Fin Carbon Fiber Rod CSTsales 2 (96in) ⅛ 8 ft Payload and Altimeter sleds: 1/16" G 10 sheet 12x24" PT 3.0 Phenolic tube 3" x 36" Performance Hobbies Public Missiles Motor tube 3" motor retainer Aeropak RA75P (75 mm) 25

27 75 54mm motor adapter Already owned by JHSRT ' 1/2" Nylon Shock Cord Already owned by JHSRT ' with sewn end loops Raven3 Altimeters Raven Perch Altimeter batteries Ejection Charge Canisters Rail buttons 1515 Already owned by JHSRT Already owned by JHSRT Already owned by JHSRT Dog House Rocketry Dog House Rocketry Recovery Altimeters Magnetic Arming Switch Li poly 130 mahr Battery Medium sized charge wells Pair of 1515 rail guides 7 foot main parachute Already owned by JHSRT 2 foot drogue parachute Already owned by JHSRT " Ellipsoidal chute " parachute Nomex protection for main 12x24 & drogue 12x12 FCP 24x24 JB Weld for motor mount attachments Top Flight Recovery Lowe's Home Improvement "x24" Nomex sheet oz tubes 26

28 Z Poxy 30 minute 8 oz glue Hobbylinc Motor Case 75mm or 54 mm Loaned by Dave Morey K1000T P Motors Misc (U Bolts, quick links, all thread, nuts, bolts, t nuts, sandpaper, tape) Balsa Machining Local home improvement stores, other sources $25 hazmat Subscale 2" rocket various Motors for subscale rocket Aerotech Motor case for subscale rocket (29/40 120) Loaned by Dave Morey Spray Paint (Primer and Color) Walmart Trim Sheets MonoKote Rocket Subtotal: 1, Payload (Rotation Alignment Device) Larger Reaction Wheel 4 x 12 aluminum rod Reaction Wheel Motor (Brushless) (backup in case of damage) Aluminum stock R/C or Robot Shops Motor Controller VESC R/C or Robot Shops 2 (already bought) CPU with Gyro/Acc Sensor Sparkfun PIC UAV 27

29 (backup in case of damage) Various Speed and Temp Sensors, LED, Speaker (backup in case of damage) CPU Battery Motor Battery Remote Control (receiver, battery, servo switch), if needed Fan R/C or Robot Shops R/C or Robot Shops Already owned by JHSRT Computer Shop mm D Payload (Inflatable Location Device) 5 Latex Balloons Party City 3 (50 ct. pack) Other balloons for testing (variety) Varies Varies Varies psig Aluminum Tank Owned by Dr. LaCosse 80 SCF helium Airgas Gas handling equipment Owned by Dr. LaCosse Fishing Line Payload Subtotal: Tracking Payload GPS Tracking Radio Already Owned by Beeline GPS 28

30 Tracking Radio Ground Support Equipment Mechanical Hardware JHSRT Owned by Dr. LaCosse Local home improvement stores, other sources Icom W 32a TDOA array Icom W 7a Tracking Payload Subtotal: Travel (not including meals) Hotel Rooms (4 nights) includes contingency day regular meal costs covered by individuals per room per night rooms for students (11 students), 1 room for chaperones (2 being paid for by the team) Banquet Tickets Vehicle Rental / Fuel (6 Days) rental vans Substitute Cost (JPL) day contingenc y Travel Subtotal: Total Cost: 3,

31 Fundraising Carryover from Capital Cost Contribution from Donor Donation from 1st Jordan Alumnus District Donation Anonymous Donation Donation from 2nd Jordan Alumnus Student Contribution Left to Raise: 0 Leftover