Experimental verification of nonlinear compensation to pid control using digital acceleration control

Proportional-Integral-Derivative (PID) control has been most commonly used to operate mechanical systems. In PID control, however, there are limits to the accuracy of the resulting movement because of the influence of gravity, friction, and interaction of joints. In contrast, digital acceleration control (DAC) is robust against these modeling errors by nonlinear terms. DAC requires information of the position, velocity, and acceleration information, and this becomes a constraint on employment and development of DAC. In this paper, we propose the combined control system of PID and DAC in which DAC is used as a nonlinear compensation. This paper shows the simulation and experimental results of the proposed control method using 1 and 2-link manipulators.