Robot Location Utensil for Precise Contact-Guided Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automotive assembly lines face challenges with positioning inaccuracies and damage risks due to variations in component placement and movement during assembly operations, which existing technologies like real-time vision systems and force sensors struggle to address effectively, especially when components are sensitive and require precise handling to avoid scratches or damage.
Innovation Solution
A method utilizing a dedicated location utensil attached to industrial robots to accurately determine and register the target position on vehicle bodies, combining visual servoing and force control to ensure precise and safe assembly operations, while minimizing unwanted contact and using force sensors to detect stable contact conditions, and potentially employing polytetrafluoroethylene (PTFE) or elastomers for reduced damage risk.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If force control is used to adapt to positioning variations, then assembly operation efficiency is improved, but the risk of physical contact damage increases
Solution Approach 1:
The patent introduces a location utensil as an intermediary between the robot end effector and the component. The utensil includes a sensor element that contacts the target to detect position, while a support element provides physical support without damage. This mediator allows the system to obtain positioning information without the main component undergoing harmful physical contact.
Solution Approach 2:
The end effector is segmented into functionally distinct elements: a sensor element for detection and a support element for physical support. The sensor element is specifically designed to be resilient and capable of withstanding contact forces without transmitting damaging forces to the component being assembled. This segmentation allows different parts of the same tool to perform different functions with different mechanical properties.
2Measurement precision
If real-time vision systems and force sensors are mounted on robots, then positioning accuracy is improved, but device complexity increases
Solution Approach 1:
The patent merges the vision system and force sensing capabilities into a single integrated location utensil mounted on the robot end effector. Rather than treating these as separate systems, the utensil combines optical detection (via camera or vision sensor) and physical detection (via force sensor or load cell) into one unified tool, reducing overall system complexity while maintaining high positioning accuracy.
Solution Approach 2:
The location utensil is designed as a multi-functional device that performs both vision-based target detection and force-based position verification. This universal tool can handle various assembly tasks requiring both visual guidance and physical contact sensing, eliminating the need for separate specialized devices and reducing overall system complexity.
3Manufacturing precision
If components are handled with precise force control, then assembly precision is improved, but the risk of damage to painted surfaces increases
Solution Approach 1:
The resilient sensor element acts as a mediator that can detect precise position through controlled contact while its material properties (resilience, compliance) prevent transmission of high contact forces that would damage painted surfaces. The element deforms elastically under contact, absorbing potential damaging forces while still providing accurate position feedback.
Solution Approach 2:
The patent changes the mechanical parameters of the contact element by selecting resilient materials and designing the geometry to provide compliance. This allows the sensor element to make contact with varying force characteristics - sufficient to detect position accurately but limited to prevent surface damage. The support element parameters are similarly optimized to provide stability without excessive force.
Data Source
Figure 1
Figure 2
Figure 3a~3b
AI summary
A method is disclosed, comprising: providing a part having a target at which an assembly operation is to be performed by an industrial robot; determining the target position, by controlling the end effector of the robot to approach the target, detecting a contact between a location utensil attached to the end effector and the target and controlling the end effector of the robot at least by force control until the location utensil reaches a predetermined position relative to the target, and determining the target position as indicated by the absolute position of the location utensil when the location utensil is in said predetermined position relative to the target; registering the target position; and controlling the end effector of the robot to perform the assembly operation at the registered target position. An assembly unit is also disclosed.