Multi-Axis Positioner With 5-DOF Joints for Submicron Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hexapods, despite being the world-class multi-axis positioning stage design, are cost-prohibitive due to the need for complex computer algorithms, high-performance actuators, and precise spherical joints, making them impractical for applications requiring submicron precision at an affordable cost.
Innovation Solution
A parallel position manipulator with three to six prismatic joint actuators, each with five Degrees of Freedom, using magnetic or other actuators to support a top plate over a base plate, allowing independent movement of actuators to prevent binding and reduce the need for complex motion calculations, thereby reducing costs and increasing precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If hexapod design is used for multi-axis positioning, then positioning precision is improved, but device complexity and cost increase exponentially
Solution Approach 1:
The hexapod system is segmented into six independent actuators, each controlling one leg independently. This segmentation allows each actuator to operate autonomously without requiring complex coordinated motion calculations, significantly reducing computational complexity while maintaining positioning precision
Solution Approach 2:
Each actuator in the hexapod serves multiple functions: it provides positioning along its specific axis, contributes to overall stage stability, and can independently adjust for compensation. This multi-functionality reduces the need for additional specialized components, simplifying the overall system despite the six-axis capability
2Measurement precision
If spherical joints with tight tolerances are used to reduce slop, then positioning resolution is improved, but manufacturing cost and actuator performance requirements increase exponentially
Solution Approach 1:
Traditional mechanical spherical joints with tight tolerances are replaced with magnetic coupling mechanisms. The magnetic coupling provides precise positioning through magnetic field interaction without requiring mechanically precise spherical bearings, significantly reducing manufacturing costs while maintaining or improving positioning resolution
Solution Approach 2:
The system changes from mechanical contact-based positioning to magnetic field-based positioning. By altering the fundamental parameter of interaction from mechanical contact to magnetic coupling, the system achieves high precision without the exponential cost increase associated with tight mechanical tolerances
3Measurement precision
If hexapod with high-performance actuators is used, then positioning precision is improved, but cost increases significantly
Solution Approach 1:
The positioning task is divided into six independent actuator operations rather than requiring six actuators to move in complex coordinated patterns. This segmentation allows each actuator to use simpler, lower-cost mechanisms while achieving the same overall positioning precision through independent control
Solution Approach 2:
The system replaces expensive, high-performance actuators with simpler, more affordable actuator mechanisms. By using magnetic coupling and independent actuator operation, the system achieves comparable precision with less expensive components, making the overall system cost-effective
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables precise, cost-effective multi-axis positioning with reduced computational complexity and actuator performance requirements, achieving submicron precision without the high costs associated with hexapods.
Implementation Method 1
magnetic force, gravity, and/or a pliable polymer, such as silicone, may be employed to keep the up to five DOF pivot points in contact with their respective (that is, top or bottom) plate
Implementation Method 2
magnetic force, gravity, and/or a pliable polymer, such as silicone, may be employed to keep the up to five DOF pivot points in contact with their respective (that is, top or bottom) plate
Data Source
AI summary
A multi-axis positioning stage or positioner includes a top plate supported and manipulatable by a plurality of prismatic joint actuators. Each actuator includes an actuator joint having four or five Degrees of Freedom (DOF) with the top plate. When one or more of the actuators extends or contracts, the pivot points, or four or five DOF actuator joints, of the remaining actuators are allowed to shift to move the top plate. The actuators can be disposed between at least one base plate or base structure, and can be fixed thereto.