Mobile Redundant Robot Control for Obstacle-Aware Path Tracking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Mobile redundant robots face challenges in efficiently navigating through environments with obstacles due to their redundancy, which complicates path planning and collision avoidance.

Innovation Solution

A method for a mobile redundant robot that involves determining the position of obstacles and using the robot's base and arm to move in a way that avoids collisions, utilizing redundancy to optimize path traversal, with a controller managing the movement of the base and arm to minimize deviation from predetermined positions and paths.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the robot uses its redundancy to avoid obstacles by moving the mobile base, then the robot's flexibility and adaptability improve, but the computational complexity of resolving redundancy and planning paths increases

Engineering Contradiction:
Improveobstacle avoidance capabilityVSAvoidcomputational complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The control task is segmented into two independent parts: (1) determining the mobile base pose that avoids obstacles while satisfying task constraints, and (2) calculating the robot arm joint angles to reach the desired position. This segmentation reduces the overall computational complexity by breaking down the redundant degree of freedom resolution into manageable sub-problems.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The method first determines the optimal mobile base pose before calculating the robot arm configuration. By preliminarily resolving the base position using obstacle information and task constraints, the subsequent arm angle calculation becomes simpler and more efficient, reducing overall computational burden.

Inventive Principle:
Principle #10Preliminary action

2Manufacturing precision

If the robot resolves redundancy to precisely approach predetermined positions, then positioning precision improves, but the time required for computation and movement increases

Engineering Contradiction:
Improvepositioning precisionVSAvoidcomputation time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The positioning task is divided into two sequential steps: first determining the mobile base pose that satisfies both task constraints and obstacle avoidance, then calculating the robot arm joint angles. This segmentation allows each sub-problem to be solved independently and efficiently, reducing total computation time while maintaining positioning precision.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The control method uses feedback from obstacle position information and task constraints to dynamically adjust the mobile base pose and robot arm configuration. By continuously monitoring and adjusting based on current state, the system achieves precise positioning without excessive computation time.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3328596B1Method for controlling a mobile redundant robot
Publication Date: 2023.07.05 KUKA DEUT GMBH
  • EP3328596B1 patent drawingFigure 1A~2B
  • EP3328596B1 patent drawingFigure 3
  • EP3328596B1 patent drawingFigure 4

AI summary

A method for controlling a mobile robot with redundant degrees of freedom (ρ1, ρ2), wherein the robot has a mobile base (10) and a multi-axis robot arm (20), and the mobile base (10) travels along a route and at the same time the robot arm (20) travels along a predefined path (B), wherein the robot detects an obstacle (40) which is located on the route, and the route of the mobile base (10) changes in such a way that a collision with the obstacle (40) is avoided. The robot arm (20) is controlled here in such a way that the predefined path (B) is travelled along further, i.e. the TCP still remains on the predefined path (B).