Autonomous Flight Control System - AFCS MK5

Autonomous Flight Control System MK5 or AFCS MK5 is a model rocket flight computer that is compact and runs on an on-board autonomous flight software that is designed to allow for complete guidance and full roll control for experimental model rockets, as it integrates physics-based calculations, sensor fusion, and active feedback control in-order to stabilize a model rocket. This project had gone through various iterations from MK1, MK2, MK3, MK4 and lastly MK5. From an inspiration by having a burning desire to push the realm of rocketry beyond the limits of basic simple passive stability, hence this project fully integrates together advanced avionics into simple PCB that is designed for measuring flight data such as orientation, servo positions, altitude from sea-level and in correcting instability in real-time, while providing full telemetry to the user after the flight.Fundamentally the AFCS MK5, relies on a 9-Axis MPU6500 IMU to combine Accelerometer and Gyro data via a Common filter to provide reliable pitch, roll, and yaw (after creating a hard-coded yaw reference) data all during powered maneuvers. Altitude data via altimeter and peak altimeter sensing comes from a BMP180 barometric sensor. Velocity and location data comes from a NEO-6M GPS module. All data is written to an auto-incrementing CSV file.

Other than its functionalities and capabilities, AFCS Mk5 also holds great educational value. Being based on real-world aerospace systems such as inertial data fusion, PID control, telemetry data logging, and events detection, it provides a great learning area for educational institutions to teach basic principles related to rocket science, physics, embedded systems, and control systems, as well as having the ability to develop more complex systems while keeping cost low. In this context, it would be very educational for students in a classroom environment to be able to learn about areas such as acceleration, angular velocity, aerodynamics, as well as feedback control systems by observing them in their actual use in flight. In this context, it would be very educational to be able to learn about areas such as graphing data from logged telemetry data to observe theoretical systems in their actual hardware form.

Based on this live orientation data, AFCS Mk5 controls two high-speed SG90 servos coupled to 2x sophisticated fins. The PID algorithm quickly analyzes how far the rocket deviates from its desired orientation and instructs the servos to control the angles of the fins to correct roll and pitch errors in mere milliseconds. The system is also redundancy-minded allowing for undisrupted data collection if any sensor loses connection or fails. In such situations, AFCS Mk5 automatically continues to collect data from other sensors and even attempts in reconnecting to disconnected sensors in the background.