The onboard computer SHARC
Our onboard computer SHARC is tasked with keeping our rocket on the right flight path, with communicating to us via radio where the rocket is located, and with deploying the recovery system. During the development of this system, our focus always laid on safety before, during, and after the flight. We value trustworthy vendors and high-quality parts. Of course, that causes our development to be more expensive, but losing our whole rocket due to an electronic failure would be far worse, and far more expensive.
SHARC consists of several different components: The main data processor, a Teensy 4.1, the self-developed MCB extension board, and many different subsystems like GNSS sensors, a radio module, or multiple linear motors.
As we are currently still in development of the rocket, all information on this page might change while time goes on. Check the news for updates about big changes.
The MainControlBoard (MCB) is used for flight data collection and to manage communication between all components and the main data processor (HC). It is also responsible for executing the control commands and was developed by us for this specific purpose. All movement sensors are located here, which transmit their information directly to the HC. The HC calculates the needed control commands, feeds analog signals to the linear motors in the TVC mount, and supervises the movements. The MCB also acts as an interface to the batteries and to the TipControlBoard (TCB).
The TipControlBoard is located in the nosecone of the rocket and serves as the mounting location for our radio-based equipment, so the LoRa and the GNSS. To locate our rocket, we use the combined data of inertial measurement units (IMUs) and GNSS modules. The IMUs deliver a short term, very accurate movement profile of the rocket according to which we calculate our steering. The GNSS will help to refine the location over time, correct extreme measurement errors, and to find the landed rocket.
The most important data is also sent to the ground station via a LoRa transmitter. That way, we can always monitor the location of our rocket, see its battery charge and keep an eye on milestones like Max-Q or parachute deployment.
Thrust vector control system
The physical steering of the rocket is done by moving the solid fuel motors oft the rocket. The Gimbal is powered by linear servos which are controlled by the motor controllers on the MCB. Their movement is monitored with built-in potentiometers and is then corrected. Our design allows for 8 degrees of freedom in all directions and can move between 8° opposite positions within one second.