Weaving Welding Robot Braking Control via Residual Deflection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for pendulum welding require manual adjustments of time or path constants based on movement parameters, making the programming of industrial robots for precise braking at reversal points cumbersome and inefficient.
Innovation Solution
The method automates the determination of the braking point for the welding tool by calculating a delayed braking movement based on residual deflection values, eliminating the need for manual adjustments and ensuring the welding tool stops as close as possible to the reversal point without prior knowledge of movement dynamics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If manual adjustments of time or path constants are made based on movement parameters, then the braking precision at reversal points can be improved, but the programming complexity and time consumption increase significantly
Solution Approach 1:
The system determines the actual reversal point automatically based on measured residual deflection values from previous oscillations. The controller uses this self-measured information to calculate and adjust the braking point for the next oscillation, eliminating the need for manual programming of time or path constants while achieving precise braking at reversal points
Solution Approach 2:
The controller measures the residual deflection value after each oscillation and uses this feedback information to determine the optimal braking point for the subsequent oscillation. This closed-loop feedback mechanism automatically adapts to variations in movement parameters without requiring manual reprogramming, thus maintaining high braking precision while simplifying the programming process
2Ease of manufacture
If empirical time or path constants are used for braking initiation, then the programming process becomes simpler, but the braking accuracy decreases because these constants must be manually adapted to each situation
Solution Approach 1:
Instead of relying on pre-programmed empirical constants that require manual adaptation, the system automatically determines the braking point by measuring the actual residual deflection value from the previous oscillation. This self-service approach eliminates manual adaptation while achieving accurate braking, effectively reversing the traditional trade-off between programming ease and braking accuracy
3Manufacturing precision
If the welding tool is stopped exactly at reversal points, then the welding quality improves, but the cycle time increases due to frequent stopping and starting
Solution Approach 1:
The controller calculates and initiates the braking action in advance based on the measured residual deflection value before the welding tool reaches the reversal point. By determining the optimal braking point beforehand and executing it smoothly, the system ensures the welding tool stops precisely at the reversal point for high welding quality while minimizing unnecessary stopping time, thus improving productivity
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for weaving welding at least one workpiece (21) by means of a welding tool (18), which is moved automatically by a robot arm (1a) of an industrial robot (1) along a programmed path relative to the workpiece (21), and thereby produces a weld seam (25) on the workpiece (21), comprising the steps of performing a programmed feed movement by the robot arm (1a) along the programmed path; executing a pendulum movement of the welding tool (18) which is synchronous to the feed movement; braking the feed movement within a pendulum period (P1) up to a standstill (S) before the pendulum movement has reached its next inversion point (U); determining a residual deflection value (R) which is defined by a first position (S) at standstill and a second position (U) at the next reversal point of the pendulum movement; and braking the feed movement in a following pendulum period (P2) with a brake movement which is delayed from a previous pendulum period as a function of the residual deflection value (R).