An Identification Method of Physical Parameters for Positioning Mechanism

Abstract

The positioning mechanism can be regarded as a simple vibration system with one degree of freedom. Generally speaking, it is difficult to identify the physical parameters of this mechanism without decomposing. In this paper, an identification method of physical parameters for positioning mechanism is described. Firstly it is shown that the viscous damping of slide mechanism can be derived by measuring the frequency response from the collocated sensor to the non-collocated sensor. Moreover, the spring constant between the mechanism also can be derived more accurately in comparison with the value based on the impulse response. Secondary the equivalent viscous damping is calculated by means of the constant velocity test or the frequency response. Then the viscous damping of rotation mechanism may easily be derived by subtracting the converted viscous damping, which is the value of slide mechanism at the position of motor axis, from the equivalent viscous damping. Finally, the proposed identification method is applied to an actual positioning mechanism.