The Accuracy Of SCARA Robot Based On Screw Theory

Accuracy is one of the important indicators of industrial robots, and it plays an important role on the robot design, production and application. At the present stage, there is still a large gap between robots made in our country and abroad, so it has an important and profound significance to analyze the accuracy of industrial robots and to study the error sources that affects the accuracy of industrial robots. In this paper, the accuracy of industrial robots is analyzed based on Screw Theory. The main contents are as follows:1,Based on Kinematics model, built the expression of screw-error caused by structural error and kinematic error and take SCARA industrial robot as an example to analysis the position and orientation errors caused by error sources. By this analysis, obtained larger factors affecting the accuracy of SCARA industrial robot, and obtained the main forms on accuracy affected by error sources. It provided theoretical basis for the design and manufacture of different types of industrial robots, reduced costs and improved design efficiency.2,Analyze the influence of deformation error under the impact of the inertia force and gravity. To see the inertia force as external force then the system becomes a static system. So the robot system can be analyzed on rigidity by screw theory and we can obtain the size and form of the deformation error on the accuracy of the robot to guide the direction for the design of the high-speed and lightweight industrial robots.3,The static factors and dynamic factors which affect the accuracy of the robot were integrated. In the design and manufacture of industrial robots, by controlling the direction of the static errors can neutralize the impact of dynamic errors, so the synthetic accuracy of robots can be improved.4,Analyze the error space of industrial robots caused by error sources. Analyze the sensitivity of error sources and obtain the trend and the level influence caused by every error parameter. It provides the basis for further design, optimization and accuracy analysis of industrial robots.