A control method of the robot arm based on the least squares method for robot experiment teaching

Abstract

The invention discloses a robot arm control method based on the least squares method for robot experiment teaching, which includes: collecting an image of an object, calculating the position coordinates of the object through the image of the object; setting the pick-up distance, and selecting several The first sample point and the second sample point, use the swing steering gear to control the gripper to move according to the first trajectory and the second trajectory in sequence; read the PWM signal duty ratio S in the swing steering gear, and calculate D i = the value of S / P; based on the least square method for x i Perform fitting to obtain the fitting equation: adjust the pick-up distance, set the duty cycle of the PWM signal in the swing steering gear accordingly according to the fitting data and control the movement of the gripper according to the first trajectory and the second trajectory in sequence; control the gripper to close Complete the grabbing of the target and extract the uplink. The invention adopts the least squares method to fit, greatly simplifies the calibration steps for realizing the trajectory, is beneficial to improving the picking efficiency of the mechanical arm, and facilitates the use of robot experiment teaching.

Description

technical field [0001] The invention relates to a robot manipulator, in particular to a least square method-based manipulator control method for robot experiment teaching. Background technique [0002] At present, the image recognition and positioning of the robot is generally: the distance between the target object and the robot is calculated and then sent to the control system of the robot arm, and the robot arm is used to control the robot to pick and place the target object through the steering gear, and the general robot arm will use two linkages mechanism, each link is driven by a single servo. In the process of moving, since the claw needs to be vertically lowered from a certain height to the predetermined target position, it is hoped to move along a vertical downward trajectory, but in fact the two-bar linkage mechanism driven by the steering gear is difficult. Accurate implementation: [0003] Specifically, the two-link mechanism of a manipulator generally include...

AI Technical Summary

Problems solved by technology

In the process of moving, since the claw needs to be vertically lowered from a certain height to the predetermined target position, it is hoped to move along a vertical downward trajectory, but in fact the two-bar linkage mechanism driven by the steering gear is difficult. Accurate implementation:

[0003] Specifically, the two-link mechanism of a manipulator generally includes a large arm, a small arm, and a gripper. Assume that the coordinates of the position picked up by the gripper are P(y, z), so the following relationship can be obtained where θ 1 is the angle between the boom and the horizontal plane after the steering gear controls the boom rotation, θ 2 is the angle between the forearm and the extension line of the big arm, l 1 and l 2 are constants; taking the inverse function of the above relational expression, we get It can be seen from the above formula that θ 1 and θ 2 In the implementation process, the value is more complicated, has a greater impact on the grasping, and has a nonlinear coupling relationship, which adds a certain degree of difficulty to the calibration of the trajectory, especially the trajectory that moves to the target position.

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