Skewed and Circular Conveyor Boundaries for Robot Picking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for defining a robot's picking area on a conveyor restrict it to straight perpendicular boundaries, leading to inefficiencies such as increased 'Position not reachable' errors, reduced picking area, and software complexity, especially when obstacles are present.
Innovation Solution
The introduction of flexible boundary definitions, allowing for skewed and circular boundaries that can be positioned relative to the conveyor flow direction, enabling the robot to pick objects while avoiding obstacles and maximizing the picking area without additional programming.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If the distance between perpendicular upstream and downstream boundaries is increased to maximize the picking area, then the robot can pick more parts, but the probability of 'Position not reachable' error increases
Solution Approach 1:
The patent applies asymmetry by allowing the upstream and downstream boundaries to be skewed at different angles relative to the conveyor flow direction. This asymmetric boundary configuration enables the picking area to be maximized while avoiding unreachable positions, as the boundaries can be independently adjusted to match the robot's actual work envelope geometry rather than being constrained to symmetric perpendicular lines.
Solution Approach 2:
The patent incorporates circular boundaries that can be superimposed on the support surface to define the picking area. This circular geometry better matches the robot's natural circular work envelope, allowing the robot to operate within its optimal reach zone while avoiding positions that would cause 'Position not reachable' errors, thus maximizing reliable picking area.
2Reliability
If complex custom programming is implemented to prevent the robot from picking in not reachable areas, then the 'Position not reachable' error is avoided, but the robot software complexity and expense increase
Solution Approach 1:
The patent implements preliminary action by pre-defining the picking area boundaries (skewed straight boundaries and/or circular boundaries) before robot operation begins. The robot controller is configured with these boundary parameters in advance, so the robot automatically operates only within the valid picking area without requiring complex real-time programming or custom error-handling logic during execution.
3Ease of manufacture
If only straight perpendicular boundaries are used to define the picking area, then the boundary definition is simple, but it is impossible to maximize the picking area when obstacles are present in the work envelope
Solution Approach 1:
The patent applies dynamics by making the boundary configuration flexible and adaptable. The system allows boundaries to be dynamically selected between straight skewed boundaries and circular boundaries, and these boundaries can be positioned at various angles and radii. This dynamic boundary definition enables the picking area to be optimized for different obstacle configurations while maintaining ease of setup through parameter selection rather than complex programming.
4Productivity
If the picking area is extended to include edge areas of the work envelope, then the picking rate improves, but the robot may attempt to pick parts in unreachable positions
Solution Approach 1:
The patent implements parameter changes by allowing the boundary angles and positions to be adjusted to match the robot's specific work envelope characteristics. By configuring the skewed boundaries at optimal angles and positioning circular boundaries with appropriate radii and centers, the system expands the picking area to include previously unreachable edge areas while maintaining reachability through parameter optimization rather than physical modification.
Data Source
AI summary
A method for controlling motion of a robot relative to a conveyor flow direction of a moving conveyor includes the steps of: establishing a tracking frame for coordinating a position and movement of the robot relative to an object support surface of the conveyor; setting an upstream boundary perpendicular or skewed to a conveyor flow direction of the conveyor; setting a downstream boundary perpendicular or skewed to the conveyor flow direction; optionally setting a circular boundary partially overlapping the upstream boundary and the downstream boundary, wherein the upstream boundary, the downstream boundary and the circular boundary are positioned to define a picking area relative to the support surface; and operating the robot to pick objects from the picking area.