Adaptive control of a two axis gimbal system using auxiliary error structure

In this article, the adaptive control of a two axis gimbal system which can revolve in the pitch and yaw directions and its parameters are uncertain, is considered. It is desired that the line of sight of gimbal system tracks a trajectory regardless of outer forces. Mechanical part of the gimbal system is modeled in Adams-View software which considers all the details and therefore exact behavior of system can be simulated. This model is linked to Matlab and an online co-simulation is run. The controller design is based on inverse dynamics approach and adaptive strategy which results in a non-Strict Positive Real (non-SPR) error model. To overcome the problem of non-SPR error model, an auxiliary error structure is implemented for updating the controller parameters. Simulation results on the gimbal system shows that auxiliary error structure has a better performance in comparison with adaptive control with modified error structure.