Robot joint torque signal acquisition system and method

Abstract

The invention relates to a robot joint torque signal acquisition system and method, and belongs to the technical field of robots. The measurement interference noise is divided into harmonic mechanicaltransmission noise, power frequency electromagnetic interference noise and sensor measurement errors. An adaptive oscillator is designed to model the power frequency interference noise and harmonic transmission noise mathematically, a state transition equation and an observation equation are established, and the inherent noise of the system is estimated and separated. Meanwhile, aiming at the defects of a torque prediction method based on a dynamic model, a torque state prediction algorithm based on weighted quadratic regression is adopted, and the accuracy and the rapidity of state prediction are improved. A Kalman filter is used for filtering uncertain noises existing in the system transfer equation and the measurement equation, the measurement torque data and the prediction data are fused, the amplitude, the phase and the frequency of the inherent interference noise of the system and the real torque output value are subjected to unbiased optimal estimation, and the denoising filtering of the torque signal is realized.

Description

technical field [0001] The present invention relates to the technical field of robots, in particular to the technical field of robot control, and specifically refers to a system and method for collecting torque signals of robot joints. Background technique [0002] The torque sensor at the end of the robot is used to detect the magnitude and direction of the contact force / torque between the manipulator and the environment, and feed back to the force control system, which is an important symbol of robot intelligence. The design of the torque sensor at the end of the manipulator enhances the human-computer interaction capability. It is an indispensable measurement component for wearable rehabilitation / load-bearing robots, collaborative robots and flexible manipulators. It not only ensures the safety of the robot's own work, but also realizes The flexible contact between man and machine ensures the safety and comfort of man-machine interaction. Accurate and fast output torque ...

AI Technical Summary

Problems solved by technology

Based on the motor current detection method, the torque output of the joint is estimated through the input current of the robot joint and the motor model. Since the direct torque output of the motor needs to be transmitted to the load end through the harmonic reducer, the friction model of the harmonic reducer transmission device is unknown and highly nonlinear. , and there is an error in the mathematical model of the motor, which leads to the inability to accurately perceive the torque output at the end, and there are shortcomings such as large torque perception delay and low sensitivity; the sensing method based on the torque sensor collects the value of the torque sensor at the end of the joint and performs a series of filtering The denoising process is used to measure the torque output of the joint, which improves the rapidity of torque measurement. However, due to the large amount of measurement noise, interference noise and electromagnetic interference noise introduced by the circuit system in the torque sensor signal, the traditional non-model low-pass filter denoising method method, it will cause the phenomenon that the accuracy of the torque measurement signal is reduced and the delay is increased

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