PID control method for industrial robot with preset performance

Abstract

The invention discloses a PID control method for an industrial robot with preset performance. The PID control method comprises the following steps that on the basis of a traditional position type PID control method, a position tracking error e (k) is converted into a transformation error epsilon (k) with an upper bound, and the position tracking error meets the condition. By means of the PID control method for the industrial robot with preset performance, the influence of proportional Kp, differential Kd and integral Ki parameters in the traditional PID control method on the steady-state tracking error of an end effector is weakened, and the constraint on the steady-state position tracking error requirement of an industrial robot control system is enhanced. The invention provides a strong-robustness control method with a preset steady-state position tracking error, and the influence of the continuously changing dynamic performance and external environment in an industrial robot control system on the control performance is solved within a certain range.

Description

technical field [0001] The invention relates to the field of industrial robot control, in particular to a PID control method of an industrial robot with preset performance. Background technique [0002] The rotating speed of the industrial robot system in the prior art is generally around 3000RPM in the state of high-speed rotation. Under such high-speed repetitive working conditions, each joint of the robot will generate a large centrifugal force, and the centrifugal force will increase with the increase of the rotational speed. Larger centrifugal force will greatly increase the steady-state tracking error of the industrial robot control system, and the steady-state error will gradually increase with the interference of factors such as industrial robot aging, mechanical wear, and external rotation, which makes the traditional PID method pass Fixed proportional, differential and integral parameters are difficult to adapt to complex working conditions. At the same time, wit...

AI Technical Summary

Problems solved by technology

However, this application-oriented method cannot exhaust all possible situations, and its development cycle is long, the controller complexity is high, the development cost is high, and the robustness of the control system is low

[0005] Industrial robot control systems generally use position-based PID algorithms, which have the advantage of high calculation accuracy, but also have disadvantages: each sampling point needs to accumulate the tracking error e(k), because the integral term (PI) directly acts on the controller , it is very easy to cause the integral saturation of the controller, which will cause the instability of the control system; with the change of the dynamic performance of the industrial robot and the external environment, its PID control system cannot always guarantee the steady-state tracking error of the end effector within the initial design within range

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