High-Acceleration Precision Point-to-Point Motion Control With Look-Ahead Properties

This paper investigates the effects of two control algorithms on high-performance point-to-point motions. The emphasis here is to overcome challenges in precision positioning of high-acceleration tables in the presence of significant external disturbances and exited vibration: an A-type of iterative learning control (ILC) (A-ILC) algorithm for repetitive motions and a look-ahead finite impulse response (FIR) filter plus sliding-mode control (SMC) for nonrepetitive motions. The model-free convergence condition and the fastest converging parameter equation for A-ILC are given in the frequency domain. Then, the FIR coefficients are decided through the ILC results and modified to eliminate the friction effect. Experimental studies demonstrate that both the algorithms perform well and the FIR-SMC algorithm is robust in various experimental scenarios which include high acceleration (of 73.7 m/s² or about 7.5 g), model parameters, and disturbance deviations from the position, velocity, and acceleration at which the ILC (and, hence, FIR) is trained.