First Nation's Launch (2021)
The video shows the launch date for last year's First Nation's Launch competition. The challenge for this year's rocket competition was to initiate an onboard anomaly at some point during flight. Our design incorporates a 3D-printed hatch door that opens and closes during the rocket's flight. For our efforts, the NAU Space Jacks took 3rd place in the competition and won the Judges' Award. I helped build this rocket and created the Aftermovie video.
This Year's Launch (2022)
First Nation’s Launch is a collegiate rocket competition involving over thirty tribal Universities in Northern America. Wisconsin Space Grant Consortium, in collaboration with NASA, offers the program as a part of furthering the rocketry industry and fostering the growth of Native and indigenous peoples in the field as a whole. Each year, specific challenges related to the model rocketry competition change. This year’s launch competition involves the utilization of a cold gas thruster subsystem to spin the model rocket to an angular velocity of 120-240 RPM . Spin stabilization is a well-researched phenomenon where an object traveling in a given direction will experience a stabilizing effect when some level of angular acceleration in a perpendicular direction to the motion of the body is applied. For example, this is utilized in the stabilization of both satellites and bullets when expelled from the muzzle of a firearm. The cold gas thrusters must initiate spin during the coast phase of the rocket’s ascent. The rocket will spin at the aforementioned angular velocity for three seconds until initiating cold gas release in the opposite (counterclockwise) direction to slow the spin to zero RPM. Once the rocket reaches apogee, the onboard electronics will initiate black powder charges both aft and forward to the cold gas thruster subsystem to release the drogue and main parachutes at their respective heights. The cold gas thruster subsystem will remain within the payload tube of the rocket for the entirety of its descent to mitigate damage to the system.
Our Solution to the Challenge
Going from best practices in the industry and a series of concept generation and elimination techniques allowed for the creation of the cold-gas thruster subsystem seen here. Cold gas is stored in the tank sitting forward of the model rocket. The avionics bay sits at the bottom of the CGS. An accelerometer will be used to determine when the rocket is in the coast phase of its flight. Specifically, the coast phase will occur when the rocket's engine has burnt out entirely and the rocket continues to increase in altitude. At this moment, the accelerometer will see a sharp decrease. Two solenoids will be used to allow air flow through two thrusters. Power will open the solenoids with thrusters facing in the clockwise direction. Expelled air from the tank will allow the target angular velocity to be hit. Once this has been reached, the counterclockwise solenoid will receive power to slow the angular velocity back to zero.
Download the Final Proposal
As VP of Rocket Club and leader for the capstone project, I am personally responsible for team delegation. In the above document, I have highlighted my personal contributions to both writing and design.
Creating the Prototype
As the only member of my capstone group with any electromechanical experience, the lion's share of building the prototype fell to me. The prototype presentation required us to answer a specific question about the build. Our capstone professor said a good prototype for us would be to attempt to power a solenoid with an Arduino and relay.
As you can see from the whiteboard to the right, my idea for this presentation was to show where the devices will fit as the cold gas thruster subsystem comes together over time. The Arduino connects a 12V power supply to a solenoid through a relay. The relay works to facilitate the connection of the solenoid to the power supply, thereby powering it and allowing the free flow of air. When the Arduino powers the relay to close the switch, a clicking of the solenoid can be heard. This was displayed in a presentation where the solenoid could be heard clicking to the on and off position depending on the frequency of the Arduino powering the 12V relay. It was not an easy process for me to set this up. Beyond this, I've come to discover that relays do not perform well under intense G force.
I have also created a load cell array with an Arduino microcontroller for use in testing the force of thrust generated by the released air sometime next semester.
This year's challenge is proving to be exceptionally difficult. I am confident that I, my capstone team, and the rocket club are putting in the required effort to have a successful launch on April 21, 2022.
I personally have spent over 193.82 hours on this project since last semester and anticipate spending around 250 hours more. Currently, I rank in the 5% of time spent on a student's capstone project across all sections.