For increasing the optimal design accuracy of reappearing trajectory of link mechanism

the positions and the numbers on the locus of link mechanism must be suitable.Based on this

a new design method is proposed under the condition of discrete points and number is constant.Cubic spline interpolation in Matlab spline function is used on those points to get the mathematical interpolation curve model of the trajectory

then adds discrete points on the interpolation curve based the change rate

so the reappearing trajectory of optimum design of link mechanism is come to pass by fmincon function in optimistic toolbox of matlab.In comparing with the traditional optimization design method

this method can greatly improve the efficiency and accuracy because of adding interpolation points on the trajectory.The method is suitable to any optimal design of reappearing trajectory mechanism

so it has certain practical value.