Parallel Kinematic Assembly Position Determination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing parallel kinematic devices face challenges in determining the position and orientation of a platform relative to a frame without measuring the lengths of connecting elements, leading to high computational effort, non-unique solutions, and limitations in working space and stability due to the need for additional sensors.
Innovation Solution
The device uses alignment determination units on connecting elements with translational and rotational degrees of freedom to determine the platform's position based on alignment data, eliminating the need for length measurements and reducing the number of required sensors, thereby simplifying the calculation and enhancing stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If forward kinematics is used to calculate platform position from active link positions, then the position can be determined, but high computational effort is required due to high degree solution polynomial and multiple non-unique solutions
Solution Approach 1:
The patent extracts the length measurement function from the active connecting elements and transfers it to separate alignment determination units. This separation allows the kinematic calculation to use only alignment data, eliminating the need to process length measurements and significantly reducing computational complexity while maintaining position determination accuracy.
Solution Approach 2:
The alignment determination units act as intermediaries between the active connecting elements and the position calculation system. These units provide alignment data that serves as a simplified mediator, replacing the complex length measurement data and reducing the computational burden of solving the forward kinematics equations.
2Productivity
If additional sensors are used to simplify forward kinematics solution, then computational effort is reduced, but working space is limited and device complexity increases
Solution Approach 1:
The alignment determination units perform multiple functions: they determine the alignment of active connecting elements, provide data for position calculation, and eliminate the need for separate length measurement sensors. This multi-functionality reduces the overall sensor count and avoids the working space limitations that would result from additional sensors.
Solution Approach 2:
The patent combines the alignment determination and length measurement functions into a single integrated approach using alignment determination units. By merging these functions, the system achieves simplified kinematics calculation without requiring additional separate sensors that would constrain the working space.
3Device complexity
If length of active connecting elements is measured directly, then position calculation is simplified, but measurement complexity increases due to guided/non-guided drives and rotational degrees of freedom
Solution Approach 1:
The patent replaces direct mechanical length measurement of active connecting elements with optical or sensor-based alignment determination. This substitution eliminates the complexity of measuring lengths in elements with both translational and rotational degrees of freedom, as alignment data can be obtained more easily than direct length measurements in such complex mechanical systems.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The invention describes an apparatus (10) comprising a frame (12), a platform (14) and a plurality of first connection elements (16) which have one translational degree of freedom and up to one rotational degree of freedom. The first connection elements (16) are connected to the frame (12) by means of second connection elements (18) having at least one rotational degree of freedom, and are connected to the platform (14) by means of third connection elements (20) having at least one rotational degree of freedom. The apparatus (10) also comprises a device (24), wherein two, three or more of the first connection elements (16) are provided with orientation determination units (22), and the device (24) is configured to determine a position and an orientation of the platform (14) relative to the frame (12) on the basis of orientation data from the orientation determination units (22).