Optimal control method for robot trajectory planning based on obstacle size homotopy strategy

Abstract

An optimal control method for robot trajectory planning based on obstacle size homotopy strategy. First, the motion equation and constraints are established according to the robot's structural characteristics, and its outline is described by a characteristic circle. Secondly, according to the obstacle information in the working environment, the characteristic circle is used to describe and set the safety distance, and the obstacle avoidance conditions in the working process are established. Third, determine the initial and terminal boundary conditions corresponding to the robot trajectory planning problem. Fourth, the trajectory planning problem is transformed into an optimal control problem to minimize energy consumption. Finally, the constructed optimal control problem is transformed into a series of sub-problems, and the size of the obstacle in each sub-problem is continuously increased compared with the previous sub-problem, and the solution of the current sub-problem is used as the initial guess of the next sub-problem. The invention utilizes the obstacle size homotopy strategy to realize the efficient and stable solution of the point-to-point trajectory planning problem of the robot in a complex operation environment, which is of great significance for solving the trajectory planning problem faced by the robot in actual operation.

Description

technical field [0001] The invention belongs to the field of robot trajectory planning, and relates to an optimal control method for robot trajectory planning based on obstacle size homotopy strategy. Background technique [0002] Commonly used robot trajectory planning methods include graph theory method, artificial potential field method, search method, rapid expansion random tree method, optimal control method, etc. Compared with the other types of methods mentioned, the optimal control method makes the planned trajectory naturally feasible because it is based on the kinematics (or dynamics) equations of the robot. In addition, the optimal control method has a simple mathematical structure, and various constraints such as control saturation and obstacle avoidance can be considered under a unified framework. There may be many obstacles in the actual working environment of the robot. Using the optimal control method to solve the optimization problem will lead to a highly n...

AI Technical Summary

Problems solved by technology

There may be many obstacles in the actual working environment of the robot. Using the optimal control method to solve the optimization problem will lead to a highly nonlinear optimization problem, making the robustness and efficiency of the solution process heavily dependent on the quality of the initial guess.

Since the robot must be in a delicate waiting state before the trajectory planning is completed, if the solution efficiency is slow or fails, it will affect the progress of the entire job task

This objective fact limits the application of the optimal control method in the actual robot trajectory planning problem

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