Robot Workspace Optimization and Deformation Compensation in Grinding
Industrial robots are becoming a key component of modern manufacturing due to their flexibility and low-cost. However, the motion singularity and weak stiffness caused by the open series structure of the robot have a strong influence on its positioning accuracy and machining quality. In this paper, considering the dexterity and stiffness illustrated above, the method of workspace optimization and grinding deformation error compensation are utilized to improve the precision of the robot grinding. First of all, the robot dexterity analysis is carried out to obtain its dexterous workspace. And then, the workspace stiffness distribution is analyzed with the compliance ellipsoid model, which results in the acquisition of stiffer workspace. Finally, the characterization method of grinding normal deformation is proposed by setting the material removal rate as an index, and the way to compensate this deformation is brought out accordingly. A robot grinding experimental platform in this paper is set up based on KUKA KR210-2 to validate the method aforementioned. The accuracy is improved from 0.148 mm to 0.189 mm, which verifies the effectiveness of the proposed method.
KeywordsRobot grinding Dexterity Stiffness Workspace optimization Deformation compensation
This work was supported by China Scholarship Council (No. 201706295033) and the National Science and Technology Major Project of the Ministry of Science and Technology of China (Grant No. 2017ZX04011011).
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