Research On Design And Dynamic Simulation System Of Planar Cam

Based on the analysis of the advance treads in the field of mechanics and the practical requirement, a new planar cam design theory model was proposed. And then using the new model, the planar cam design and simulation system were developed. It provided a more general and simple method for cam designs, and could ensure the follower follow the special movement rule or the special track.In the paper, based on the method of low pair replacing with high pair, the problem of cam design was transferred to that of linkage design. By means of rotary unit vectors, the equations of displacement, velocity and acceleration of the replacement mechanisms were developed. And then, the virtual linkage's length and direction were deduced. Based on that, the theoretical and practical cam profile, curvature radius and pressure angle were calculated. Then the center's track equation of the circular cutter which was used to manufacture the cam was presented. For the problem of designing on combined cam mechanism which follows the given track, typical nodes in the track were selected at first. Then the spline interpolation method was employed to plot the smooth track. Finally, the combined cam mechanism was designed. This method could avoid the input of many trace points, and decrease the work times.Using VB6.0 and related interface functions, a user-friendly interface of the design and dynamic simulation system of cam mechanism was developed. It could plot the track of the movement, produce the related documents and simulate the cam movement dynamically. By using ActiveX techniques to call the objects in AutoCAD software, the cam profile could be plotted interactively, the system could used to design the cam for planar and combined cam mechanisms in the fields of engineering simulation, design, and computer aided instruction(CAI).