I am working on designing a controller for an optical beam tracking system with multiple actuators. I can sense the angle of an incoming light beam that moves based on two sources. The first is the movement of the target, which causes a slow movement of the incoming angle of the beam, and the second is the local platform angular jitter, which has both low and high-frequency content.
I have a single detector which detects the sum of these disturbances. I also have two actuators which effectively reject these disturbances. The first actuator has a first-order linear response, with a relatively slow response, and the second actuator has a fast, lowly-damped second order linear response. The first actuator has a large range and the second actuator has a small range.
I have designed a state-space regulator using a kalman estimator and a lqr controller designed in MATLAB with one input (the measured angle) and two outputs (the two actuator commands). However, because the second actuator is range-limited, I would like to pass the low- frequency angular movement to the first actuator, and the high- frequency angular movement to the second actuator. Unfortunately, there seems to be no straightforward way to make this happen. Does anyone have any suggestions on how I can force the regulator to pass the low-frequency components to the first actuator and the high- frequency components to the second? Should I try a different approach to generating the regulator?
thanks, Susheem