| Under the strategic guidance of "the 14 th five year plan" and "the long-term goal of 2035",China’s manufacturing industry has entered a critical period of intelligent transformation and quality improvement.As the basic unit of intelligent manufacturing,robotic cell is the key link to realize its high-quality development by constructing efficient cell scheduling strategy.However,in large-scale complex robotic cell,it is difficult to reasonably allocate the loading and unloading sequence of dual-arm robot and the processing sequence of multiple parallel machines,which requires reasonable scheduling model and effective algorithm to solve the optimization problem.In this paper,the scheduling strategy of multi-robotic cell is studied based on a crankshaft production line.Firstly,according to the crankshaft production process and the characteristics of dual-arm robot handling,the multi-robotic cell scheduling problem is abstracted.By calculating the process beat and the balance rate of the production line,the multi-robotic cell which needs to be optimized is found;According to whether there are parallel machines in the process,the constraints and optimization objectives of the scheduling problems of dual-arm robotic cell and robotic cell with parallel machines are determined.Secondly,a fast periodic scheduling strategy based on robot loading and unloading operation is proposed to solve the problem of two arms parallel handling conflict.In order to minimize the completion time,a fast periodic scheduling model is established.It is proved that the 1-unit cycle scheduling of the problem is polynomial solvable,and a polynomial time algorithm is proposed to solve the robot scheduling scheme.The effectiveness of the algorithm is verified by comparing the gap between the lower bound of the feasible solution and the optimal solution.Thirdly,aiming at the complex cooperative relationship between robot and parallel machine in dual arm robot unit with parallel machine,a LCM-GA scheduling strategy based on robot loading and unloading and parallel machining is proposed..According to the characteristics of parallel machining sequence and dual-arm robotic handling,the LCM scheduling model is established,and the improved genetic algorithm is proposed to solve the approximate optimal scheduling scheme.The LCM-GA hybrid scheduling strategy is simulated by a production line example,and compared with the FIFS scheduling strategy to verify the effectiveness of the LCM-GA scheduling strategy.Finally,the fast scheduling strategy and LCM-GA scheduling strategy are used to schedule the actual processing cell of the production line,and the approximate optimal scheduling scheme of the multi-robotic cell is obtained,which can better solve the scheduling problem of the multi-robotic cell. |
