A new optimization method for dynamic design of planar linkage with clearances at joints - Optimizing the mass distribution of links to reduce the change of joint forces

This paper presents a new optimization method for dynamic design of planar linkage with clearances at joints. The general consideration is to optimize the mass distribution of links to reduce the change of joint forces. The mass, the center position of mass and the moment of inertia the moving links are taken as the optimizing variables. The objective functions are taken as the changes of the amplitude and direction of the joint forces and them are minimized. The optimized result shows that the magnitude of joint force can be controlled hardly to change and the direction of joint force can be controlled to change smoothly with respect to the crank angle, although the clearances exist at the joints. The link shape can be formed with the optimized variables by using the small element superposing method (SESM) and a design example is given.