3D Trajectory Error Display for Machine Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current display devices for machine tools fail to accurately quantify and visualize errors in three-dimensional trajectories, making it difficult to intuitively identify and diagnose issues in the actual trajectory compared to the commanded trajectory.
Innovation Solution
A trajectory display device that calculates the error between the actual and commanded positions of a machine tool's three-dimensional trajectory by determining the shorter length of either a normal line or a line segment connecting the actual position to the commanded position, and visually represents this error through color and line thickness changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If combined positional deviation is used to represent trajectory error, then the error can be displayed in a simple manner, but the error does not correctly indicate the deviation of actual position from commanded trajectory
Solution Approach 1:
The patent replaces the conventional mechanical approach of combining positional deviations with a mathematical/geometric approach. By calculating the perpendicular distance from actual position points to the commanded trajectory curve, the system achieves accurate error measurement without the inaccuracies of simple deviation combination. This substitution of calculation methodology resolves the contradiction between simplicity and accuracy.
Solution Approach 2:
The patent introduces an intermediary geometric construction - the perpendicular distance measurement - as a mediator between the commanded trajectory and actual position. This intermediary approach provides a clear, accurate, and intuitive representation of trajectory error that overcomes the limitations of direct positional deviation combination while maintaining computational feasibility.
2Loss of information
If combined positional deviation is displayed, then trajectory error can be visualized, but it takes time to specify problems and find causes
Solution Approach 1:
The patent applies color changes to visually encode trajectory error information. By displaying the perpendicular distance errors with color variations, the system enables rapid identification of problem areas and their causes, reducing the time required for diagnosis while preserving complete error information.
Solution Approach 2:
The patent adds a visual dimension to trajectory error representation by using color and graphical display of perpendicular distances. This dimensional enhancement transforms abstract numerical errors into intuitive visual information, allowing operators to quickly identify and diagnose trajectory problems without losing error details.
3Device complexity
If positional deviation is calculated at discrete time intervals, then calculation is simplified, but the deviation does not represent the true distance to commanded trajectory
Solution Approach 1:
The patent applies dynamic calculation methods that adapt to the trajectory geometry. By calculating perpendicular distances from actual positions to the commanded trajectory curve at discrete intervals, the system maintains computational efficiency while achieving accurate error measurement. The dynamic adjustment of calculation approach based on trajectory characteristics resolves the contradiction between simplicity and precision.
Data Source
AI summary
A trajectory display device capable of correctly quantifying an error of a three-dimensional trajectory of a machine tool, and displaying or outputting the error. The trajectory display device has a command line segment defining part adapted to define a command line segment which connects two temporally adjacent points, in relation to each commanded position; an error calculating part adapted to define a normal line extending from the actual position to each command line segment and calculate an error of the actual position relative to a commanded trajectory, the error being determined as a shorter one between a length of a shortest normal line among the defined normal lines and a length of a line segment extending from the actual position to a commanded position which is the nearest from the actual position.