Parallel Link Calibration System for Six-Axis Force Sensor Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing calibration apparatuses require configuration changes based on load magnitude and suffer from sliding resistance errors, making calibration less efficient and accurate.
Innovation Solution
A calibration system featuring a stage, weighting jig, parallel link mechanism, and control apparatus, where a weighted body is fixed between the stage and jig, and six rods apply loads in six axial directions, allowing for precise calibration without configuration changes or sliding resistance issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If wire and pulley are used to convert gravity into load in six axial directions, then the calibration apparatus can apply load in multiple directions, but sliding resistance is generated between the wire and pulley causing measurement errors
Solution Approach 1:
The patent replaces the wire-pulley mechanical system with a parallel link mechanism consisting of six rods. This substitution eliminates the sliding friction between wire and pulley by using direct mechanical connections through rods that can be precisely controlled by output parts, thereby maintaining six-directional load application capability while significantly improving measurement accuracy.
2Adaptability or versatility
If the number or type of weights is changed according to load magnitude, then different load ranges can be covered, but the apparatus configuration becomes complex and requires frequent adjustments
Solution Approach 1:
The patent creates a universal calibration apparatus where the parallel link mechanism with six rods can generate loads of different magnitudes through controlled displacement of output parts without changing the basic apparatus configuration. The system achieves multiple load ranges by varying the displacement amount rather than changing physical components, making the apparatus multi-functional and eliminating the need for frequent reconfiguration.
Solution Approach 2:
The patent introduces dynamic control through the parallel link mechanism where the load magnitude is adjusted by controlling the displacement of output parts rather than using fixed weights. This dynamic adjustment capability allows the apparatus to adapt to different load requirements by changing the position of movable components rather than reconfiguring the entire system.
3Device complexity
If a fixed apparatus configuration is used, then device complexity is reduced, but the ability to apply different load magnitudes is limited
Solution Approach 1:
The patent maintains a relatively fixed apparatus configuration while achieving load magnitude adjustment through dynamic control of the parallel link mechanism. The six rods connected to output parts can be displaced to different positions, allowing the same structural configuration to generate various load magnitudes. This dynamic positioning capability provides adaptability without requiring complex reconfiguration of the apparatus.
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
Enables easier and more accurate calibration by eliminating the need for configuration adjustments and minimizing sliding resistance, ensuring precise load application in six axial directions.
Implementation Method 1
The parallel link mechanism includes six rods. The parallel link mechanism includes output parts corresponding to the six rods, respectively. The six rods are connected in parallel to the weighting jig. The control apparatus controls an output of each of the output parts, relatively displaces the weighting jig with respect to the stage, and calibrates the force sensor on the basis of the value output from the force sensor and the load value output from the master sensor.
Implementation Method 2
The weighted body includes a force sensor configured to output a value based on a load value including at least a component in one axial direction among components in six axial directions of a load applied to the weighted body
Implementation Method 3
The calibration apparatus disclosed in Patent Document 1 converts gravity applied to the weight into the load in six axial directions applied to the weighted body by the wire and the pulley.
Data Source
AI summary
A calibration system including a stage, a weighting jig, a parallel link mechanism, and a control apparatus is provided. A weighted body includes a force sensor configured to output a value based on a load value including at least a component in one axial direction among components in six axial directions of a load applied to the weighted body, and a master sensor calibrated to output the load value according to the load. The parallel link mechanism includes output parts corresponding to the six rods, respectively. The six rods are connected in parallel to the weighting jig. The control apparatus is configured to control an output of each of the output parts, relatively displace the weighting jig with respect to the stage, and calibrate the force sensor on the basis of the value output from the force sensor and the load value output from the master sensor.