The calculating formula of the velocity instant center coordinate in X&Y direction at random time of the working table and the coordinate measuring error of the random position on the working table which is caused by the linearity error was deduced.

This article puts forward the similarity between the instantaneous acceleration center of plane motion of rigid body and the acceleration center of the fixed axis rotation of rigid body and gives the method of locating the instantaneous acceleration center of plane motion according to the characteristic of the rotating center of the fixed axis of the rigid body.

based on analysing acceleration with method of base point,analyses how thelocation of the instantaneous center of acceleration is fixed under different circumstances anddetermines rapidly and accurately the acceleration of various points on the rigid bodyes of plannarmotion with the analytic method of the instant aneous center of acceleration.

The instantaneous center of velocity and the instantaneous center of acceleration for rigid bodies in plane motion are presented in this paper,and some methods of ascertaining are given,using the theorem of momentum moment of instantaneous center of velocity and acceleration can simplify in some problems.

Based on analysis of the nature of cicq modle,propose a new conception-instant speedup and effective speedup,then point out that instant speedup is a resource in cicq modle.