Industrial robot rigidity identification system based on six-dimensional virtual joint model and identification method of industrial robot rigidity identification system

Abstract

The invention discloses an industrial robot rigidity identification system based on a six-dimensional virtual joint model and an identification method of the industrial robot rigidity identification system. The system comprises an industrial robot, a carrying force loading device and a laser tracker. A six-dimensional force measuring tool is mounted at the tail end of the industrial robot, and thecarrying force loading device is composed of a mounting slab and four hollow stand columns. Two force loading points are arranged on each hollow stand column, and each force loading point is providedwith a force loading mechanism composed of a force loading direction convertor, a lasso and a weight. The carrying force loading device is provided with eight force loading mechanisms and can exert loads to the tail end of the industrial robot in a multi-pose manner, so that measured data fully reflects the rigidity change of the robot, and rigidity parameter identification of the industrial robot can be achieved better. According to the identification method, an industrial robot rigidity error model is built based on the six-dimensional virtual joint model, the rigidity characteristic of theindustrial robot can be described completely by the model, and the industrial robot tail end positioning precision is effectively improved.

Description

technical field [0001] The invention relates to the technical field of industrial robot parameter calibration, in particular to an industrial robot stiffness identification system and an identification method based on a six-dimensional virtual joint model. Background technique [0002] As the focus of the development of high-end manufacturing industry, industrial robots have become an important symbol to measure the level of scientific and technological innovation of a country. With the rapid development of robot technology, the application fields of industrial robots are also expanding, such as hole making and riveting in the aerospace industry. These applications have higher and higher precision requirements for industrial robots. The absolute positioning error of industrial robots is mainly divided into geometric parameter errors and non-geometric parameter errors, of which geometric parameter errors account for about 90% of the total error, such errors can be compensated...

AI Technical Summary

Problems solved by technology

At present, the joint stiffness error models for industrial robots mainly include the stiffness model based on the assumption of joint flexible rotation deformation and the supplementary stiffness model based on the assumption of joint flexible rotation deformation. Due to flexibility, there is only compliance deformation along the direction of joint rotation, while ignoring robot assembly deformation, connecting rod deformation, and stiffness parameters in other dimensions. When the load at the end of the robot is large, it may still lead to large positioning errors.

At present, the static load method of the robot is often used to identify the stiffness of industrial robots, but the identification system has problems such as the complexity of the implementation of the stiffness identification experiment, especially when the load on the end of the flange plate of the robot is less, and the measurement data cannot fully reflect the stiffness change of the industrial robot. It will lead to low identification accuracy of industrial robot stiffness parameters, which will directly affect the control accuracy and control performance of industrial robots

Images