The paper deals with the dimensional synthesis of movement of a seven-bar mechanism based on the genetic algorithm. The seven-bar mechanism is part of a sheet metal bending machine which defines the trajectory of the movement of the bending beam and the load transmission function. By moving the beam the sheet metal is deformed or bent, and its path of the movement affects the quality of the finished product (deformed sheet metal) and the size of the load in the mechanism. The thesis describes the process of creating an optimization algorithm that, based on the calculation of kinematic points of the mechanism, approaches the motion of the bending beam to the reference path. The reference path describes the ideal path of the movement of the bending beam, the shape and size of which depend on the machine geometry and the sheet metal thickness. Its two main advantages are the movement of the beam without damaging the sheet metal and reduction of the total force with the zero relative motion of the beam in relation to the sheet metal deformation. An optimization 2-D model of the seven-bar mechanism of the beam motion has been developed, which, on the basis of the size of the design variables, gives the actual path of the mechanism, and the goal function calculates the deviation of the path of the movement of the beam from the reference path. On the basis of different sizes of the mechanism and their values of goal functions, the genetic algorithm seeks the most appropriate solution, the path of the movement of which is most appropriate. The structure of the developed algorithm is such that by changing the constant design variables the size and shape of the optimized mechanism change as well, while the path of the movement is maintained. Thus, several different shapes of the mechanism with a similar path are obtained, and the choice of the most suitable one is increased.
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