Robot Arm Runtime Safety Limits for Flexible Operation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing robot safety systems cannot dynamically adjust safety limits during operation, limiting flexibility and increasing certification requirements, as they must be changed when the robot is powered off, which complicates implementation and cycle time.
Innovation Solution
A robot system with a robot process controller and a robot safety controller that can evaluate and adjust safety limits in real-time, using a combination of basic and process control software, allowing for dynamic changes to safety limits while the robot is operational, ensuring the more restrictive limit is always applied for safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If safety limits are adjusted when the robot is powered off, then safety is ensured, but implementation time and cycle time increase
Solution Approach 1:
The patent applies dynamics by enabling safety limits to be adjusted in real-time during robot operation rather than requiring power-off adjustments. The robot controller dynamically modifies safety parameter values (such as speed limits, force limits, or position limits) based on current operational context, allowing the safety system to adapt to changing conditions while the robot remains operational, thus reducing implementation time and cycle time without compromising safety.
2Adaptability or versatility
If safety limits are fixed and cannot be changed during operation, then certification requirements are reduced, but flexibility and adaptability decrease
Solution Approach 1:
The system enables dynamic adjustment of safety limits during robot operation, allowing safety parameters to be modified in real-time based on operational context. This dynamic capability provides flexibility and adaptability for different working conditions while the controller manages the complexity of multiple safety limit configurations through automated selection logic.
Solution Approach 2:
The patent implements parameter changes by allowing safety limit values (such as maximum speed, maximum force, or position boundaries) to be modified during robot operation. The controller can switch between different sets of safety parameters depending on the current task or environmental conditions, providing adaptability without requiring complete system redesign or recertification for each scenario.
3Reliability
If multiple safety limit values are maintained, then safety is ensured, but system complexity and processing overhead increase
Solution Approach 1:
The controller manages multiple safety limit parameter sets by dynamically selecting and applying the appropriate parameters based on current operational mode or task. Rather than maintaining all parameters simultaneously active, the system switches between different parameter configurations, ensuring safety through multiple defined limits while managing complexity through automated parameter selection rather than manual configuration of all possible limits.
Data Source
AI summary
A robot system comprising a robot arm controlled by a process controller according to a combination of basic software and process software and a safety controller configured to monitor and evaluate operation of a robot arm. The basic software is associated with safety limits having normal values limiting operation of the robot arm. The process software is associated with at least one safety limit having a process value which is different from the normal value. The value of a safety limit is configured to be updated with the process value while the robot system is in run-time mode and the robot safety controller is configured to bring the robot arm into a violation stop mode based on the result of an evaluation of an operation parameter, the normal value and the process value of the at least one safety limit.