Development of hardware-in-the-loop simultion for rocket guidance system

This paper focused on the design and implementation of the autopilot and Proportional Navigation based guidance system on the rocket. Autopilot system is implemented with three-loop autopilot scheme with pitch and yaw acceleration command input, and two-loop autopilot to keep the roll angle fixed. Autopilot system is designed by using linear models of rockets on the state of Mach 0.7 and angle of attack 0°. Autopilot control command is obtained from the guidance system. Guidance system processing kinematics and dynamics of rockets, as well as target sensing inputs, into acceleration command in order to obtain desired movement of a rocket. Flight attitude, angular rate, and inertia of rockets are provided by the navigation system. While the target sensing inputs in the form of Line of Sight (LOS) are obtained from the seeker. Guidance and autopilot system are implemented on the ARM-based board, TWR-K60D100M, while navigation system and nonlinear models are implemented in MATLAB using the Hardware-in-the-Loop Simulation (HILS). The results showed that the designed autopilot is stable with acceptable performance in nonlinear models testing and also in digital implementation. Integration with the navigation system and HILS implementation indicate that the system is able to hit a moving target and resulted less than 5 meters final position error in windy conditions.