As of Summer I 2018, two capstone projects are working with Project Karman to design a spin stabilization system. The first capstone group is working on the mechanics and design of a spinning rocket and canted fins, while the other group is designing a low-volume mechanical de-spin system for the rocket.
Many key decisions that will be the bedrock of the final rocket have been locked in. We hope to prove our designs for various subsystems in a Fall 2019 low altitude launch and a Summer 2019 high altitude launch. If these are a success, procurement and fabrication of the 6 meter tall final rocket will begin.
Project Karman had a successful start to 2017. The first rocket we launched was the NUSC Lazarus, the successor to the Parachute Test Rocket. It was launched in Price MD, at MDRA on March 15th. We launched again at LDRS on April 8th with Karman’s first two stage rocket named Two Infinity and Beyond (infinity is the booster section, and Beyond is the sustainer). The NUSS Lazarus flew as the sustainer in the two stage configuration. (needs rewording). Unfortunately, the second stage motor did not ignite and the sustainer did not separate from the booster on ascent. Both rockets were however recovered in perfect condition, and reached an altitude of 4327 ft.
The rocket flew perfectly straight in 15mph winds, and had a very successful flight to an apogee of 1885 feet. Like its predecessors, NUSC Lazarus was a subscale of our final sustainer stage, designed to test dual deploy from a single bay with the use of a Tender Descender, and CO2 ejection with a Peregrine ejection system. The previous two rockets and three launches all experienced critical recovery failures, but all of the kinks were worked out with this launch. The 24” drogue was deployed at apogee with the CO2 ejection system, while the main chute stayed in the rocket. At 500 ft agl the main 60” chute was released from the body, very gently setting the rocket on the grass; before pulling it across the field, the mud, and the street. This iteration was unique as the fins were shifted up 3.5” from the bottom of the rocket, so that it could fly as the sustainer rocket in our two stage.
Infinity and Beyond was the Karman Project’s first two stage rocket. It was the second one for Northeastern’s AIAA, but the first that was two separate rockets, rather than one main rocket with a booster section. The main elements tested in this flight were the drag separation between the booster and sustainer stages in flight, and the ignition of the second stage motor with the use of a head end ignition system. The rocket failed to separate due to some design factors, such as a teflon interface which may have added friction, as well as an electrical failure to ignite the head end initiator. This led to Project Karman to making and testing new electronics for a new flight system.
2016 was a busy year for Project Karman. The team as a whole grew to nearly 40 active members, with six to seven sub projects each semester. Two different rockets were launched; Infinity and Heighliner. Unfortunately due to recovery issues, both rockets failed and crashed ballistically. More information on each rocket can be found in later sections.
After the failure of Infinity in mid May, the team rebuilt the same rocket named Beyond over the summer, with a completely revamped avionics system. A live telemetry system that reports 15 sets of data at 20 Hz to a ground station was developed in parallel. The design theory behind the new system was that in the event of a total failure, information on the flight could still be recovered and used to identify the issue. Additionally the information gathered from the flight will be used to validate the simulations that we have created.
The two rockets are identical except for the avionics bay. To mitigate risk Heighliner was developed. Heighliner was a test of the experimental recovery system that Infinity I was using, including a CO2 deployment system and deployment of the main chute from a single bay using a quick release system. The first flight of the rocket resulted in critical failure, where the recovery system did not deploy and the rocket crashed ballistically. The rocket was rebuilt and the system tested again on Heighliner II, resulting in a partial deployment of the recovery system. Heighliner II was salvageable after the first flight, and was able to be re-launched a second time with a new recovery configuration, unfortunately the system failed again and resulted in a third ballistic recovery.
In its latest iteration, the NUSS Lazarus was developed to isolate problems, and develop a rocket to test the experimental parachute system, in a way that has a high chance of success. The exact cause of the previous failures has not been identified, however post crash analysis points to an avionics bay issue as some of our pyrogen did not ignite in flight. To combat failure, we have slowed down our development process, and are waiting to begin construction until all designs are fully finalized and reviewed by members of the club. As of December 31st 2016, the NUSS Lazarus is nearly fully designed with a new 3D printed avionics bay, and is set to begin construction when classes resume January 9th.
The underpinning of this club has always been a love for space and an excitement for challenges. The Karman Line Project encapsulates the ethos of AIAA at Northeastern. The primary objective: be the FIRST university to successfully build and launch a rocket to 100 km above sea level. 100 km is designated as the Karman Line, the altitude at which the Earth’s atmosphere is separated from outer space. We plan to eclipse this boundary with our custom-designed three stage rocket. Led by a group of senior engineering students who founded AIAA at Northeastern, this project will be our most technically challenging to date. With an aggressive schedule of laboratory tests and sub-scale launches this fall, we hope to launch our full-scale rocket in spring 2016. At 17 feet tall and 200 pounds, our current models predict an altitude of 115 km. From that vantage point, we will take a picture of the earth hanging in its orbit about the sun. This picture of our home planet, along with data of our position, will be shared with all. We hope to use this picture and the project to inspire more students to pursue space exploration.
Launch Vehicle System
Total Length: 5.18m (17ft)
Total Mass on Pad: 92kg (203lb)
Apogee Altitude: 115km
Time to Apogee: 178 seconds
Max Acceleration: 229m/s^2 (23.4g)
Max Velocity: 1421m/s (Mach 4.78)
1x Cesaroni O8000
Total Impulse: 40960N-s
2x Cesaroni O3400
Total Impulse: 21062N-s
*Must be modified for head-end ignition*
Avionics System – EECE Capstone Project
Team members working on an EECE capstone project have chosen to design and fabricate the avionics system for the Karman Line rocket. The avionics consist of a flight computer to trigger flight events, determine altitude, take imagery, and transmit all data back to a ground station. Each stage of the rocket will have avionics, the first and second stage having stripped down versions of the main flight computer in the third stage. The flight event timing will require an array of sensors determining rocket orientation, speed, and acceleration. Pyrotechnic circuits will trigger events such as stage separation and motor ignition. GPS will determine altitude and a small cell phone grade camera will take imagery. The flight computer will also interface with a globalstar transmitter as a technology demonstration in collaboration with the MIT Lincoln Laboratory. Globalstar is a satellite constellation used for on earth tracking. This rocket allows us to test connectivity of the globalstar network from space. This demonstration has implications for the cube satellite industry, allowing small inexpensive satellites to maintain communication with users at all times. The EECE capstone team is working to design custom PCBs and test them in rigorous flight-like environmental tests.
Stage Separation – ME Capstone Project
The mechanical engineering Capstone team has chosen to design the stage separation system for the Karman Line project. The concept of a staged rocket is not new to the club, but the Karman Line project faces a stricter set of requirements and a much harsher environment than previous rockets built by the club. A higher overall degree of precision is required for the project in order to reached the desired altitude. This necessitates an accurate and controllable stage separation system. The Capstone team has researched existing stage separation system designs and has created a custom solution for AIAA. The separation mechanism consists of two rings that fit together and are connected by pyrotechnic bolts. The team has designed a nylon bolt with a hollow core that is filled with an explosive powder. At a specified time, the avionics system will send a signal to the bolts and trigger separation. Two stage separation systems will be used in total: one to separate the first and second stages and one to separate the second and third stages. The team is currently testing and refining the design and will deliver a final product to AIAA for installation into the Karman Line rocket.
Nose Cone and Airframe
Fiberglass with aluminum-capped nose cone
Fin Design and Attachment
Fiberglass core and wrapped in Carbon Fiber
Alternative Fin Design – Aluminum Fin Can
Pros: Ease of construction (or off-the-shelf) and ease of analysis
Cons: Heavier than Carbon Fiber and NAR restrictions on metal parts
Drogue and Main Parachute on Each Stage – Fruity Chutes
Both chutes located in the same chamber
Considerations: Elimination of drogue in first stage; use of a Tender Descender
CD3 CO2-Based System
Pre-made Black Powder Capsules