Application potential of articulated coupled drive and guide elements for increase of movement dynamics and accuracy

• Applicant: Professor Dr.-Ing. Steffen Ihlenfeldt
• Subject Area: Production Automation and Assembly Technology ; Engineering Design, Machine Elements, Product Development ; Production Systems, Operations Management, Quality Management and Factory Planning
• Term: from 2015 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 269296582

The trend for cutting machine tools towards increasing dynamics for both conventional feed axes as well as machines for high-speed cutting (HSC) leads to significantly higher inertia forces in relation to the process forces. One approach for solving this dynamic problem is to use multiple drives per axis (parallelization). Profile rail guides and ball screws are established as standard machine elements in many areas of engineering, particularly in machine tool engineering, for guides and drives of linear axes. They are designed in such a way that they allow motion only in guide direction, feed direction, and about the feed axis. When combining them to one feed axis, even small form deviations and/or deviations regarding the elements position to each other lead to mechanical tensions. In order to ensure high quality of motion and reduce mechanical stresses due to overdetermination, very small manufacturing and assembly tolerances are required. However, lowering these manufacturing and assembly tolerances has technical and/or economic limits. The in-control correction is one potential solution for reducing the motion error by using parallelized drive axes. The method requires articulate structural connections to attach drive and guide elements to the structure. In machines with parallelized drives, such as servo spindle presses with a plurality of spindles or tool machines with gantry drives, additional mechanical overdetermination occurs in the direction of motion. For this problem articulate structural connections are also potential solutions. Objective of the proposed research project is, therefore, to fundamentally and systematically investigate the potential of parallel drives with articulated drive and guide elements to increase dynamics by mechanically decoupling parallel drive axes and to improve accuracy by correcting motion errors. In order to achieve these goals, parametric machine models with parallel drives for analyzing representative axis configurations and structural dimensions in digital block simulations are developed. By means of these models, which consist of drives, controllers, and elastic structural components, and a systematic variation of the main influences, a study is conducted which allows for determining the requirements and limits of application of parallel drives with articulate connections between drive and guide elements and the structure for isolation and correction purposes.

• DFG Programme: Research Grants
• Co-Investigator: Dr.-Ing. Jens Müller