On the output motion characteristics of variable input speed servo-controlled slider-crank mechanisms

The input speed of the crank of a slider-crank mechanism is traditionally assumed to be constant. However, this paper proposes a novel concept by varying the speed of the crank to obtain the desired output motions. This approach uses a servomotor as the power input of the mechanism. By properly designing the input speed of the mechanism, the output motion can pass through a desired trajectory. The input motion characteristics are planned with Bezier curves. Optimization is used to improve the output characteristics of the system. Guidelines for defining the optimization problems are discussed and control algorithm regarding how this servo system works is presented. Three design examples are given to demonstrate the procedure of this work. Results of experiments are also given to verify the feasibility of this work.