Drive based vibration damping on industrial robots for milling operations

• Applicant: Dr.-Ing. Armin Lechler
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: from 2016 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 290804444

In the area of easily machinable materials and large-volume workpieces, there is a desire to use industrial robots as a cost-effective alternative to conventional machine tools. This is primarily a result of the high number of degrees of freedom, the required space and the significantly more favorable ratio of workspace to investment costs. However, this trend is countered by the disadvantages of limited absolute accuracy as well as the sensitivity to vibration, which has a negative effect on the machining quality and the achievable metal removal rate. During the first funding period, two different control methods based on the joint positions were designed and implemented. It has been shown that the vibrations excited by the interaction of the process forces and the robot structure can be damped drive-based. Thus, the accuracy and productivity of robot machining cells can be improved. The key issue of the second funding period is whether the improvements achieved in a small workspace can be extended to the entire workspace. For this purpose, the locally valid drive-based vibration damping method, which was developed in the first funding period, will be modified using gain-scheduling to ensure its functionality in the entire workspace. It is the only way to fully exploit the potential of industrial robots for machining large-volume workpieces.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr.-Ing. Alexander Verl