Galil Motion Control (Rocklin, CA) has released Frequency Analysis Software (FAS), which allows tuning of servo control systems in the frequency domain. Tuning in the frequency domain is often preferred for systems with resonances or when the design engineer is comfortable with classroom control theory. The new software in conjunction with a Galil motion controller measures the frequency response of the plant to be controlled. It simulates the possible control solutions and synthesizes the two to allow for Bode analysis of the closed loop system.
FAS plots the magnitude versus frequency and phase versus frequency for both the Galil motion controller and the plant. The plant’s frequency response is measured from the actual plant. The controller’s response is simulated based on the selected control parameters. The product of the two functions is the system open loop frequency response.
The Frequency Analysis Software allows the designer to try various simulations of the controller parameters such as the PID filter and notch parameters and combine them with the plant to give the open loop frequency response. Based on the simulations, the designer can determine the best controller parameters to meet the desired performance criteria of phase margin and cross-over frequency for his system.