ASTRo is a High-Power Rocket (HPR), developed in parallel with the Starscraper vehicle. While not powered by a hybrid engine like BURPG’s other designs, it was designed to use similar stabilization and control systems to gain experience in implementing these systems.
The control surface actuation follows two different formulations depending on the regime of the flight. The first regime is subsonic, where the formulation uses a constant multiplier on the dynamic pressure from CFD tests. The second regime uses compressible flow relations to find the pressure on the control surfaces. These formulations are calculated by the Kronos Lite flight computer, a simplified version the avionics system used on Starscraper.
The servos are mounted on a 3D-printed fin can, transferring the load to the airframe. To ensure that it is safe to fly, material properties test samples were printed in the same printer.
The rocket uses a dual deployment recovery system, firing a smaller drogue parachute at apogee, slowing its descent to a controlled rate. At 1100 feet AGL, the Raven3 Recovery Control Board fires the charges that release the main parachute, which deploys to slow the rocket for a safe landing. For tracking, the nose cone has a 70cm GPS and the main body has an RF beacon tied to the shock chord of the main parachute.
After being flown during the 2014-2015 academic year, ASTRo was rebuilt to utilize a different IMU better suited for a flight environment, optimized avionics, more reliable recovery, and a better on-board camera. Further analysis of the airframe and vehicle dynamics is also being done to better understand the behavior of ASTRo during flight. ASTRo will undergo several more flights during the Spring 2016 semester.
Height: 90” (2.3 m)
Launch Mass: 50 lb (22.68 kg)
Diameter: 6 in (15.25 cm)
Motor: Cesaroni L1050
Burn Time: 3.6 sec
Average Thrust: 235.15 lbf (1.046 kN)