Abstract: A novel motion model is proposed for the follow grinding of crankshaft. In which, noncircular follow control strategy is investigated on the basis of servo linkage of horizontal feeding shaft and additional lifting shaft for grinding wheel, and the turning shaft for workpiece. The straight line relationship of grinding wheel center, pin center and cut point are ensured by the synchronism between the arc interpolation motion of grinding wheel and the eccentric circular motion of pin. Consequently, constant line-speed precise grinding of pin is achieved. The negative influence of perpendicularity error between horizontal feeding shaft and additional lifting shaft is kinematically analyzed as well as the response error of numerical controller. Hence the solving methods are carried out respectively. By the computer simulation analysis and application test, the presented follow grinding motion model exhibits good characteristics in the manufacturing of crankshaft, such as strong adaptability of grinding wheel wearing, convenient machine motion control and high grinding accuracy.

Key words: Crankshaft, Error compensation, Follow grinding, Motion model, Non-circular grinding