In the past, the costly process of tuning control systems in unmanned air systems required a considerable amount of experimentation to obtain acceptable gains in bias and throw for a particular aircraft type and flight profile.
The U.S. Army Research Laboratory's Vehicle Technology Directorate has recently developed a Hardware In the Loop Simulation (HILS) that can test the aircraft feedback control laws while calibrating the onboard inertia measure unit (IMU).
Prior methods accepted a certain amount of error to be compensated by the flight control laws. The new method utilizes the Federal Aviation Administration approved X-Plane simulator as a generator of flight data.
The calibration unit simulates flying the autopilot. Using HILS, flight data is fed directly through the calibration unit and feedback data are simultaneously taken from the autopilot's IMU and sensors allowing for system optimization.
The device will act as a test platform for adaptive-learning algorithms, geo-location, and ground targeting in the future. This is a collaborative effort between Jackson State University, the University of Alabama in Huntsville and ARL.