ABSTRACT
Control algorithms are a key component of precision machine design. Strategies that employ both feedforward and feedback elements address the dual requirements of trajectory following with minimal vibration and robust disturbance rejection. Classical, frequency-domain-based design techniques apply to both linearised lumped parameter models of a motion system as well as measured frequency responses that capture behaviour not included in the model. Idealised linear lumped parameter models that replace motors with unlimited applied forces and slideways with frictionless inertial masses are widely used in developing the initial control strategy, while direct measurements are used for model refinement and final tuning. Precision motion control problems commonly include structural flexibilities, sensitivities to actuator and sensor location, multiple sensors and actuators, axis coupling and multi-loop designs. This chapter provides a starting point for students who have taken a traditional introductory controls course to identify issues of particular interest for precision controller design. References 602giving detailed developments of specific controller strategies are included for the student desiring to address particular precision motion control applications.
