Continuum Robot Control Switching for Smooth Backward Movement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Continuum robots face challenges in performing forward and backward movements without steep bending movements, especially when the attitude of bendable portions deviates from the stored attitude, leading to inefficient operations in environments with external forces.
Innovation Solution
A continuum robot with a forward and backward movement unit, an attitude change unit, and a control unit that switches between position control and back-drivable control based on attitude deviations, allowing for smooth movement and reduced external force reliance during operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the attitude of bendable portions is stored and reverted during forward movement, then the robot can maintain its path, but steep bending movements occur when looking around and then moving backward
Solution Approach 1:
The control system dynamically switches between two control modes: position control mode (when moving forward and needing to maintain stored attitude) and back-drivable control mode (when moving backward or during look-around operations). This dynamic adaptation allows the robot to maintain path stability during forward movement while avoiding steep bending during backward movement or inspection operations.
Solution Approach 2:
The system changes the control parameter state by switching between position control and back-drivable control based on the movement direction and operational state. When backward movement is detected or during look-around operations, the control mode transitions to back-drivable mode, allowing the robot to follow external forces smoothly without steep bending, thus resolving the contradiction between path stability and operation smoothness.
2Manufacturing precision
If position control is used to revert attitude to stored values, then the robot maintains its configuration, but it cannot smoothly follow external forces during backward movement
Solution Approach 1:
The control system dynamically adapts its behavior based on movement direction and operational context. During forward movement, it uses position control to maintain precise attitude. During backward movement or inspection operations, it transitions to back-drivable control, allowing the robot to adapt to external forces. This dynamic switching resolves the contradiction between maintaining precise attitude and adapting to external forces.
Solution Approach 2:
The system uses feedback from the movement direction and operational state to determine which control mode to use. By detecting whether the robot is moving forward or backward, and whether it is performing inspection operations, the feedback mechanism selects the appropriate control mode, enabling both precise attitude maintenance during forward movement and smooth force-following during backward movement.
3Adaptability or versatility
If the robot operates in confined spaces with fragile objects, then it can access hard-to-reach areas, but it risks damaging fragile objects with steep bending movements
Solution Approach 1:
The control system dynamically adjusts its control mode based on the operational context. When accessing confined spaces during forward movement, it uses position control to maintain precise path following. When performing look-around operations or moving backward in confined spaces, it switches to back-drivable control, allowing smooth movement that follows external forces without steep bending, thus reducing the risk of damaging fragile objects while maintaining access to confined spaces.
Solution Approach 2:
The system changes control parameters by switching between position control and back-drivable control modes. This parameter change enables the robot to maintain precise positioning when needed while allowing smooth, force-following movement during inspection and backward operations in confined spaces, thereby protecting fragile objects from damage while preserving access capability.
Data Source
AI summary
A continuum robot includes a forward and backward movement unit configured to cause a plurality of bendable portions to perform forward movement or backward movement in a lengthwise direction, an attitude change unit configured to cause each of the bendable portions to bend to change an attitude, an attitude memory configured to store the attitude with regard to each of the bendable portions, and a control switching unit configured to perform, when the forward movement or the backward movement is detected, in a case where an attitude of at least one bendable portion deviates to a predetermined extent or beyond from an attitude of the at least one bendable portion which is stored in the attitude memory, switching as change control of the attitude for the attitude change unit from position control for changing the attitude into a specified attitude to control for changing the attitude following an external force.