Implementation and investigation of a force control for a forming demonstrator with coupled servo drives

Abstract

In the area of production engineering, there are ongoing efforts to improve manufacturing strategies and processes in terms of stability, quality and efficiency. One possibility for ensuring stable process conditions and reducing rejected parts is closed loop control of quality determining parameters. For many applications, the machining forces often represent the limiting factor for the design of the processes and the choice of parameters. As a controlled value, they are predestined for ensuring process stability and safety. For the tasks and problems of forming technology, control of process forces is not yet mature and offers significant potential for improvement. The drafting of sophisticated control concepts, which enable a mutual use or a combination of force and position control, is the focus of future developments. The design and implementation of a force control for a forming demonstrator with coupled servo drives is described in this publication. The combination of force and position control is realized by direct switching. In addition, further combination options and structures are explained. The focus here is first on the parameterization of the force control and the assessment of the control performance using appropriate comparison criteria in the time domain.

Simulative investigation of hybrid force and position control for electromechanical feed axes in production machines

“…The basic structure and components of the mechatronic system are illustrated in Figure 2. A more detailed description of the structure and functionality of the demonstrator is given in Reference 23.…”

“…In contrast to other approaches, both controllers are integrated into the cascaded servo control at the same level. This concept was introduced for a test rig with two coupled electromechanical feed axes and a control system from Siemens in 23 . The switchover between force and position control has already been implemented and the basic functionality was proven.…”

“…The effects of the hybrid concept with simultaneous utilization of both controllers and the switchover are examined in simulation. In addition to previous research from, 23 the forming demonstrator, whose basic structure and functionality are based on a servo screw press with two coupled drives, serves as a reference machine and use case for the simulation. A comparison of the simulation results reveals the potential of this concept.…”

“…This concept was introduced for a test rig with two coupled electromechanical feed axes and a control system from Siemens in. 23 The switchover between force and position control has already been implemented and the basic functionality was proven. A similar concept was proposed for hydraulic actuators by Pasolli and Ruderman.…”