Abstract
Recently, linear ball guideway is often used for precision and ultra-precision positioning. As the linear ball guideway has rolling frictional characteristic, it is very difficult problem to achieve precision and ultra-precision positioning. Nonlinear spring behavior indicating the relationship between applied force and displacement, characteristic indicating the relationship between applied force and velocity and circular contouring error at quadrant changes are simulated by using the bristle model proposed for expressing sliding frictional characteristic when full-closed loop control is used. Precision positioning apparatus of an axis using a voice coil motor (VCM) is composed for measuring their characteristics. The simulated and measured results are compared. As a result, the simulated results using the bristle model are agreed with measured ones in both nonlinear spring and rolling area using two spring constants properly. In this study, a method of making the spring constant functions is proposed for not choosing spring constants.
