Integrated design methodology of ball-screw driven servomechanisms with discrete controllers. Part II: Formulation and synthesis of the integrated design

In order to acquire high-speed and high-precision performances in ball-screw driven servomechanisms, an integrated design methodology has been proposed. Based on strict mathematical modeling and analysis of servomechanism performance according to design and operating parameters, a nonlinear constrained optimization problem including the relevant subsystem parameters of a ball-screw driven servomechanism is formulated. A multi-objective function and nondimensional variables are introduced in the design process. Constraints for the mechanical and control subsystems render the integrated design problem accurate. Optimum design results of the mechanical and control subsystems are obtained according to the design parameters specified by designers through the integrated design process. Motors are optimally selected from the servo motor database according to the iteration process. Both geometric errors due to Abbe offset and contour errors are minimized while required constraints such as stability and saturated conditions are satisfied. This design methodology not only optimizes the dynamic performance of the servomechanism, but also improves quality of the design process to achieve the required performance for ball-screw driven servomechanisms.