Design, synthesis and control of a mechanical servo press: An industrial application

Due to precision, flexibility, simplicity in construction, easy control, higher speed and lower energy consumptions, servo presses have recently become popular in metal forming applications. Servo press technology combines the advantages of hydraulic and conventional mechanical presses without their drawbacks. This study presents design, construction and demonstration of a servo crank press system for metal forming operations. The research involves kinematics and motion optimization, dynamic modeling, structural design and analysis, servo motor selection, automation and control, and operational performances of the servo press. The press used in this work has a load capacity of 50 ton and stroke capacity of 200 mm. Firstly, optimized trajectories of ram scenarios are generated. Then dynamic modeling using Lagrange approach is presented. Next structural model is constructed, and Finite Element Analysis (FEA) of press parts are performed within safety limits. A servo motor with a reduction unit is selected based on dynamic model. After that a new automation system is developed, and Cascade Feed-Forward (CasFF) control is applied. Moreover, four motion scenarios (crank, dwell, link, and soft motion) are employed for the performance assessment of press. Finally, the dynamic model is verified by the experimental results. The research study is carried out under support and grant of an industrial project, aiming to provide know-how to industry and researchers.