The Gist: Low cost Nitrous Oxide/Isopropyl alcohol pressure fed rocket engine producing 4KN (900lbs) of thrust. Designed from the ground up to leverage metal 3D printing and assemble in as few parts as possible. The engine is going to be used on our upcoming hotfire and attempt to break the ametuer rocketry recovered liquid altitude record.

What I did/do: As the engine is entirely mechanical, ignition and engine shutoff must be performed without the aid of electrically driven actuators. In our engine, both ignition and shutoff are enacted through one poppet valve in the center of the engine. I performed the design and analysis of the engines ignition poppet valve. This valve is responsible for retaining fuel and oxidizer prior to ignition, and opening the fuel and oxidizer pathways during ignition. I performed all hand calcs to inform spring selection, designing the inner workings of the valve such that prior to ignition it can hold back the hydrostatic pressure of liquid propellants on the pad. I performed FEA in Solidworks to ensure the strength of the valve under pressure loading during firing of the engine.

The Technical Specifics: The isopropyl propellant of the engine is autogenously pressurized to 750PSI by the nitrous oxide. prior to ignition, there is a tube that goes through the center of the injector into the ignition valve. when the valve is in the preflight position, this tube supplies the nitrous into the engine, through filling channels in the engine manifold. Since the supply line, and tank are 760PSI Isobaric prior to launch, the springs within the poppet valve resist the hydrostatic pressure of the isopropanol. When the GSE ignition solenoid vents, the poppet valve slams downwards into firing position, opening the flow paths for isoproanol and nitrous. The propellants travel downwards into the injector, which is comprised of a radial array of 7 quadlets. There is enough propellant for the engine to fire for 4 seconds. No regen cooling, or resonance chambers for now... but we are working on it ;)

The Gist: The end result of a project to use fiber reinforced 3D printing materials to replace Aluminum in structural bulkheads throughout the rocket. The 3D printed assembly allowed a structrual bulkhead to serve dual purpose as the enclosure for all flight electronics.

What I did: Full mechanical, and electrical design and assembly of the avionics bay. I started with a rough bulkhead using a disc of Glass fiber reinforced nylon PA6. Using an orthotropic representation of the material properties in ANSYS mechanical, I used static structural simulations to iterate through different ways of reducing mass before settling on a wagonwheel print with a thin aluminum plate overtop. This became the basis of design that I began to add electronics too. The avionics enclosure and the avionics within it successfully deployed all parachutes and witheld all flight stresses, bringing our ~30kg rocket safely back to the ground in both of its flights.

Technical Specifics: The bulkhead was simulated to a 4000N bi-directional axial static load with a 20% factor of safety. The drag force of the parachute  is transfered via a threadded rod to the aluminum plate on the oposing side of the bulkhead, where it is then transfered to the PA6-GF print and the radial bolts through the carbon fiber body tube. The value was determined as the worst possible loading scenario for parachute deployment, the entirety of the parachute opening into the freestream instantaeneously. The entirety of the stuctural assembly weighed in at 1.2kg. Inside the avionics bay, 2 18650 Li-Ion batteries powered two blue raven flight computers, each redundantly wired to the 4 ejection charges, one pair for each deployment event. Hardware interupts were placed axially and radially, to ensure at no point during integration does a live black powder charge have a person by it.

The Gist: Custom built onboard Live video system that broadcasts video from the rocket throughout flight to a video capture system allowing the flight to be patched into a youtube or twitch livestream. Watch the video here! https://www.youtube.com/watch?v=JLir_lgI0WE&t=22671s 

What I did: I performed the systems design for all the radio, battery, and control electronics. I designed the enclosures that housed all electronics and batteries. I did all preflight testing and integration. Created custom spot welded battery packs and battery enclosures.

The Technical Specifics: We opted to use the 3.3Ghz band for our video system to mitigate frequency management issues at our competition on the common 5.8GGhz and 2.4Ghz bands. These odd band analog video transmitters made prolific by the ongoing war in ukraine come with substantial output powers. After some substantial digging we were able to able to procure a 10W actively cooled transmitter, which enabled us to receive a nearly static free video signal from 12,000 ft AGL despite the significant amount of carbon fiber and metal in close proximity to the transmitter. The video transmitter ingested video from a runcam split, which provided the HD flight recording on the vehicle from the same camera. The entire system was powered by a 4S1P 18650 Li-Ion pack I spot welded and enclosed myself. Due to it residing in the payload compartment, it had to sandwhich itself between the airframe and the cubesat of the rocket. This led to some substantial headache getting all the parts to fit, but I managed to get everything to fit without any thermal issues.

The Gist: Testbed rocket designed to fly to 3000ft repeatedly to test in development flight computers and live video systems. Every part of the rocket was designed to be hotswapped in the field for rapid repairs, and made with any 3D printer for ease of manufacturing.

What I did: I performed all vehicle simulation and preliminary design in openrocket, before designing the vehicle and avionics sled in onshape. I created a spot welded battery pack for the vehicle.

The Technical Specifics: The rocket is powered by an aerotech H135 White Lightning DMS motor. 810mm long, 51mm OD, 1049g Wet, 837g Dry. A single 18650 Li-Ion powers all flight electronics, the custom flight controller is powered direct, and there is a seperate 8.4v boost converter running the 5.8GHz live video system. The antenna is a suuuuper small right-hand circularlly polarized cloverleaf antenna, which I found was woefully under equipped for the task of broadcasting the video. In future flights I will be sizing up the antenna. This one was a quick 4 day after work project.

The Gist: Tunable seed dispensing collar and sensor suite meant to disperse forage seeds as grazing livestock walk, and measure grazing patterns of the livestock. Work performed in support of joint patent application with OSU and the Openly Published Environmental Sensing Lab (OPEnS Lab) 

What I did: Performed all mechanical design and manufacturing of collars from the ground up. I was responsible for the field testing and IMU/GPS data that I used to tune the dispensing rate of the seeds using precision orifaces on the bottom of the collar. created all graphics and documentation for patent application and presentation at the american geophysical union.

The Technical Specifics: A 3D printed housing connected a section of PVC pipe and all electronics to a livestock collar. The Collar housed an IMU/GPS that recorded the grazing patterns of the cows. I used graze times, along with the intensity of grazing as defined by the IMU to make sense of the different seed dispensing rates between cows. This data informed the diameters of small SLA printed apertures on the bottom of the tube. These were designed with a significant flare to present clogging. The vibrational data, confirmed that no clogs in the orifaces were responsible for an underdispensing of seeds during the test campaign at the OSU dairy.