Robot Motion Control Using External Force and Movement Conditions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for a technique that maintains the work efficiency of a robot while ensuring the safety of objects or workers in its periphery.
Innovation Solution
A control device for a robot that includes an external force acquisition section, a first condition determination section, a second condition determination section, and an operation control section. This device acquires external forces applied to the robot's movable elements, determines if the external force exceeds a predetermined threshold and if the movable element is moving, and stops the robot's operation when both conditions are met, while continuing operation when either condition is not satisfied.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the robot stops operation when external force is detected, then safety is improved, but work efficiency deteriorates
Solution Approach 1:
The patent applies parameter changes by monitoring multiple parameters simultaneously (external force magnitude, movement state, contact duration) rather than relying on a single threshold. The control device evaluates combinations of these parameters to determine when to stop operation, allowing it to distinguish between safe and unsafe conditions. This enables the system to maintain high safety standards while avoiding unnecessary stops that would reduce work efficiency.
2Reliability
If the robot stops operation frequently to ensure safety, then safety is improved, but work efficiency deteriorates
Solution Approach 1:
The patent applies local quality by evaluating the specific characteristics of each external force event locally rather than applying a uniform stop rule. The control device analyzes the magnitude, duration, and context of each force application independently, allowing it to permit operation for minor disturbances while stopping for significant hazards. This localized evaluation minimizes unnecessary work interruptions while maintaining safety.
Solution Approach 2:
The patent applies partial action by implementing a graduated response rather than always stopping operation. For minor external forces or brief contacts, the system allows operation to continue with enhanced monitoring. For severe or persistent external forces, the system stops operation. This partial application of the stop rule reduces time loss while maintaining safety for truly hazardous conditions.
3Productivity
If the robot continues operation without stopping, then work efficiency is improved, but safety deteriorates
Solution Approach 1:
The patent applies feedback by continuously monitoring external force sensors and movement state detectors, then using this feedback to dynamically adjust operation. The control device receives real-time data about external forces and the robot's movement state, evaluates this feedback against safety criteria, and adjusts operation accordingly. This closed-loop feedback system enables continuous operation under safe conditions while automatically stopping when harmful conditions are detected.
Solution Approach 2:
The patent applies preliminary action by establishing predetermined thresholds and evaluation criteria for external forces before operation begins. The control device is pre-configured with safety parameters and decision rules that allow it to quickly determine whether to stop or continue operation when external forces are detected. This preliminary preparation enables rapid response to hazardous conditions without compromising work efficiency during normal operation.
Data Source
AI summary
A control device for a robot includes: an external force acquisition section configured to acquire external force applied to a movable element during operation of the robot; a first condition determination section configured to determine whether or not a first condition that the external force exceeding a predetermined first threshold is applied to the movable element is satisfied; a second condition determination section configured to determine whether or not a second condition that the movable element is moving is satisfied; and an operation control section configured to stop the operation of the robot when both the first condition and the second condition are satisfied, while continuing the operation of the robot when at least one of the first condition and the second condition is not satisfied.