Robot cartesian space trajectory planning method

Abstract

The invention discloses a robot cartesian space trajectory planning method. The method includes establishing a connecting rod coordinate system and obtaining a forward kinematic equation through a kinetic modeling analysis method; solving the rotating angles of a master control joint and a middle joint according to the vector geometric property and trajectory planning requirement of the robot; seeking a relation equation including introduced variables and solving the rotating angle of the corresponding joint by means of the kinetic modeling analysis method and the solved joint rotating angle; determining whether the pose position can be reached through a vector geometric method when the trajectory planning is carried out in a task space with obstacles; and planning the continuous time variant attitudes of coupled position information to complete the planning tasks. According to the method, extraneous roots can be prevented, efficient solutions can be screened and matched, strange paths can be effectively avoided, and meanwhile, the defects of complex end trajectory planned by the joint space can be prevented and optimized.

Description

Technical field [0001] The invention relates to a method for planning a cartesian space trajectory of a robot, and relates to inverse kinematics and attitude planning. Background technique [0002] The depth and breadth of the application of industrial robots has become an important indicator of a country's manufacturing level and technological level. Since the first industrial robot was applied to General Motor’s production line in 1962, robotics technology has developed rapidly. Especially, the robot revolution is expected to become the “third time” under the background of increasing labor costs and the concept of “Industry 4.0”. The “Industrial Revolution” is an important entry point and growth point. At present, China has become the world’s largest robot market. In May 2015, the State Council issued "Made in China 2025", which clearly stated that it should focus on supporting the development and application of robotics technology and listed it as One of the ten key areas. [...

AI Technical Summary

Problems solved by technology

The current Cartesian coordinate space planning method has a large computational workload, and the attitude planning problem is complex, which leads to the possibility that the planned trajectory may approach or pass through the singular point, resulting in unsolvable consequences

Especially for robotic arms with few degrees of freedom, when the attitude planning is unsuccessful, the goal of avoiding singular positions is often achieved by sacrificing the accuracy of the end pose. However, when performing target capture, fine manipulation, etc., the sacrifice of the end pose accuracy affects the performance of tasks. successfully executed

[0009] Therefore, planning in joint space is acceptable for grasping operations with low path requirements, but when there are strict trajectory requirements, such as welding, complex algorithms are needed to ensure accuracy, and trajectory planning in Cartesian space The accuracy is unmatched by this method based on joint space planning

However, in terms of attitude planning, due to its nonlinearity and coupling, most existing algorithms use interpolation schemes, which have poor flexibility. The singularity of the planned path, even the unsolvable situation

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