Jacek Buśkiewicz

A method for optimal path synthesis of four-link planar mechanisms

The paper deals with the optimal synthesis of planar mechanisms as path generators. The formulation of the synthesis problem enables decreasing the number of design parameters. The angular position of the floating link (coupling link) connecting input and output links is described by function sine. The coupler link is treated as a free body which generates precisely desired motion. The objective is to determine the coupler dimensions for which the coupler joints approximate with a prescribed accuracy the trajectories which these joints trace in the assembled mechanism. The structural error for most typical kinematic pairs was derived in order to apply the method to a wide spectrum of four-link planar mechanisms. Compared with classical path synthesis approach, this technique measures the deviation of the paths of the coupler joints from their paths in the assembled mechanisms, not the deviation of the coupler path from the prescribed trajectory. Various modifications of the method were discussed to widen the range of possible applications. The problem was formulated as an optimization task. An objective function was constructed and minimized in searching for generators of desired motion using an evolutionary algorithm. Test paths were chosen to verify the effectiveness of the method. Numerical tests addressed also practical linkage applications. The technique was verified in the synthesis of four-bar linkage, crank-slider mechanism and mechanism with slotted link. The method was also applied to solve chosen motion synthesis tasks combining the positions and angular orientations of the link.

Design of a Feeder with the Use of the Path Synthesis Method

The paper presents the adaptation of the technique for motion and path synthesis to the problem in which the motion equations of two links are coupled. The method is employed to design a feeder for carrying products between two points. The feeder is assumed to be an one degree of freedom system of six links connected by means of revolute joints. The jaws of the gripper catch the product and transports to other work stand where the gripper releases the product and moves back to its initial position. No extra drive of the gripper is needed as the movement of the jaws is driven by the active link of the feeder. The mathematical basis of the method is presented. The problem is formulated as an optimization task. An exemplary solution is presented and discussed.

A Specific Problem of Mechanism Synthesis

Abstract A technique for path synthesis is employed to design a feeder for carrying products between two points. The feeder is assumed to be a one degree of freedom system of six links connected by means of revolute joints. The mathematical basis of the concept is presented. An exemplary solution is presented and discussed

Comparison of Some Evolutionary Algorithms For Optimization of the Path Synthesis Problem

The paper presents comparison of the results obtained in a mechanism synthesis by means of some selected evolutionary algorithms. The optimization problem considered in the paper as an example is the dimensional synthesis of the path generating four-bar mechanism. In order to solve this problem, three different artificial intelligence algorithms are employed in this study.The paper presents comparison of the results obtained in a mechanism synthesis by means of some selected evolutionary algorithms. The optimization problem considered in the paper as an example is the dimensional synthesis of the path generating four-bar mechanism. In order to solve this problem, three different artificial intelligence algorithms are employed in this study.