Designing optimal automatic cycles of round grinding based on the synthesis of digital twin technologies and dynamic programming method

The article presents methodology for designing optimal feed control cycles resistant to unstable machining conditions for a batch of parts in round grinding operations performed on CNC machines. To improve the quality and reliability of control programs for CNC machines, a digital twin (DT) is proposed to be used. It performs virtual testing of a given grinding cycle for the possibility of defect occurrence at some combination of variable technological factors. To design the optimal grinding cycle by calculating the optimum trajectory of the radial feed change cycle, we propose the dynamic programming method (DPM) used in solving the classical transport problem, in which a network of roads with intermediate stations is specified. In the task it is necessary to find the optimal trajectory of transport. The conditions for the appearance of defects detected by the DT are introduced into the system of restrictions, and the feed cycle is again optimized in the DPM optimization system. A new optimized cycle is again tested by the DT. These iterations are repeated until the DT fixes the present of a defect for the operation. The methodology proposed in the article for the synthesis of digital twin and DPM technologies at the stage of preparation of control programs for CNC machines makes it possible to guarantee the maximum productivity of the grinding operation while ensuring the specified quality of the machined surface under varying processing conditions that vary within the specified limits.