Cable-Constrained Planar Positioning for Precise Scalable Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current positioning systems, such as Cartesian robots and cable robots, face challenges in scalability and precise control due to the need for heavy bearing structures and complex nonlinear equation solutions, respectively, while also struggling to effectively constrain degrees of freedom and apply on large scales.
Innovation Solution
A planar positioning system using flexible constraint members, specifically cables, to constrain the degrees of freedom of a moving output member, with a guide mechanism and restraint mechanism that includes cable uptake and release devices and variable-radius spools to maintain precise control and scalability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If heavy bearing structures are used to constrain the output member in Cartesian robots, then the degrees of freedom are effectively constrained, but the moving mass increases significantly
Solution Approach 1:
The patent replaces rigid bearing structures with flexible cable elements to constrain the output member. The cables act as flexible constraint members that can effectively limit degrees of freedom without requiring heavy supporting structures, thereby reducing the moving mass while maintaining constraint effectiveness.
Solution Approach 2:
The patent substitutes traditional mechanical bearing structures with a cable-based constraint system. Instead of using physical bearings and guides to constrain motion, the system uses tensioned cables that create virtual constraints through geometric relationships, eliminating the need for heavy mechanical constraint structures.
2Weight of moving object
If cable robots are used to eliminate heavy moving structures, then the mass is reduced, but precise control becomes difficult due to complex nonlinear equations
Solution Approach 1:
The patent divides the constraint system into independent cable segments, each controlled by dedicated actuators. This segmentation allows the complex nonlinear control problem to be broken down into simpler independent control tasks, where each cable's tension can be controlled separately to achieve precise positioning without solving the full system of nonlinear equations simultaneously.
Solution Approach 2:
The patent implements feedback control mechanisms that use position sensors to monitor the output member's location and adjust cable tensions accordingly. This closed-loop feedback system compensates for the nonlinearities in real-time, maintaining precise control accuracy without requiring complex open-loop calculations of the nonlinear dynamic model.
3Adaptability or versatility
If cable constraints are used to position the output member, then the system achieves scalability, but constraining additional degrees of freedom becomes challenging
Solution Approach 1:
The patent designs the cable constraint system with universal applicability, where the same basic cable-actuator configuration can constrain different degrees of freedom by simply changing the cable attachment points and routing. This multi-functional design allows the system to scale to constrain multiple degrees of freedom without requiring fundamentally different mechanisms for each additional constraint.
Solution Approach 2:
The patent uses geometric dimensioning where cables are arranged in three-dimensional空间的 configurations to constrain motion in multiple directions. By projecting cable forces through spatial geometry, the system can constrain degrees of freedom in multiple dimensions using the same basic cable constraint principle, enabling scalability without proportionally increasing mechanism complexity.
Data Source
AI summary
A system and method for a planar positioning system for an output member, the system having a pair of x-coordinate linear carriages and a pair of y-coordinate linear carriages. The system has a guide mechanism for the pair of x-coordinate linear carriages and the pair of y-coordinate linear carriages. The system has a plurality of movement and constraining cables extending from the pair of x-coordinate linear carriages and the pair of y-coordinate linear carriages to the output member for driving the output, wherein the pair of x-coordinate linear carriages and the output member move in sync in the x-direction and the pair of y-coordinate linear carriages and the output member move in sync in the y-direction. A restraint mechanism restrains the output member in an additional degree of freedom besides the x- and y-directions. The restraint can be a cable uptake and release device.