CMM Thermal Shift Compensation via Computational Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing industrial machines, such as coordinate measuring machines, face reduced Z-axis measurement accuracy due to thermal expansion of components like columns, supports, and rams, which is not effectively addressed by current temperature control methods.
Innovation Solution
Incorporating a temperature detecting unit and a shift amount calculating unit that uses reference position data and thermal expansion coefficients to accurately calculate the Z-axis shift of the ram resulting from temperature changes, allowing for precise compensation and maintaining measurement accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If temperature control is implemented to prevent thermal expansion, then measurement accuracy is improved, but device complexity and cost increase
Solution Approach 1:
The patent replaces the mechanical/thermal control system with a computational system. Instead of actively controlling temperatures to prevent expansion, the system uses temperature detection combined with mathematical calculations (thermal expansion coefficients, reference position data) to compute and compensate for dimensional changes in the Z-axis direction, thereby maintaining measurement accuracy without complex temperature control hardware
Solution Approach 2:
The patent changes the approach from controlling physical parameters (temperature) to adjusting computational parameters. By detecting temperature changes and applying thermal expansion coefficients as variable parameters in calculations, the system dynamically compensates for dimensional changes, transforming a physical control problem into a computational adjustment problem
2Measurement precision
If temperature detection and calculation systems are added to compensate for thermal expansion, then Z-axis measurement accuracy is improved, but device complexity increases
Solution Approach 1:
The patent introduces temperature detection units and a calculation unit as intermediary components between the thermal environment and the measurement system. These intermediaries detect temperature changes and compute compensation values, which are then applied to correct Z-axis measurements, thereby isolating the core measurement function from direct thermal interference while adding only minimal computational overhead
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
This solution enables highly accurate calculation and compensation of Z-axis shifts caused by thermal expansion, thereby enhancing the measurement precision of industrial machines by considering the thermal expansion of columns, supports, and rams.
Implementation Method 1
a shift amount calculating unit that calculates a Z-axis shift amount of the ram along the Z-axis direction resulting from a temperature change of each of the column, the support and the ram
Data Source
AI summary
A coordinate measuring machine (industrial machine) includes: a column and a support that extend along the Z-axis; a beam being provided between the column and the support; a slider being movable on the beam; a ram being held on the slider movably along the Z-axis direction; a temperature detecting sensor and a temperature detector that detect the respective temperatures of the column, the support and the ram; and a shift amount calculator that calculates a Z-axis shift amount based on the respective temperatures of the column, the support and the ram, reference position data indicating a positional relationship between the column, the support and the ram at a reference temperature, and respective thermal expansion coefficients for the column, the support and the ram.