Machine Tool Control System for Automated Workpiece Origin Setting

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for setting a workpiece origin in NC machine tools are labor-intensive and time-consuming, particularly when using touch sensors or cameras, as they require manual intervention and precise operator control.

Innovation Solution

A machine tool control system that employs an imaging apparatus to capture images of the workpiece from multiple directions, calculates three-dimensional coordinates of a specified machining start point, and converts these coordinates into the machine coordinate system for setting the workpiece origin, with optional integration of a touch probe for contact motion and a robot or turret for positioning the imaging apparatus.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a touch probe or camera is used to obtain workpiece origin coordinates, then measurement capability is improved, but operator labor and time consumption increase significantly

Engineering Contradiction:

Improveworkpiece origin coordinate accuracyVSAvoidtime for workpiece origin setting

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The imaging apparatus captures images of the workpiece from multiple directions before the actual machining operation begins. These images are then used to calculate three-dimensional coordinates of the workpiece, which are subsequently converted into machine coordinate system coordinates. This preliminary capture and processing of spatial information eliminates the need for time-consuming manual touch probe operations during the machining setup phase.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Instead of using a physical touch probe to manually measure each point of the workpiece, the system creates an optical copy of the workpiece geometry through imaging from multiple directions. The three-dimensional coordinates are then calculated from these optical copies and converted to machine coordinates, replacing the physical measurement process with an optical information processing approach that is both faster and more accurate.

Inventive Principle:

Principle #26Copying

2Measurement precision

If manual touch probe operation is used to determine workpiece origin, then measurement capability is achieved, but operator skill and attention requirements increase

Engineering Contradiction:

Improveworkpiece origin coordinate accuracyVSAvoidease of workpiece origin setting

Core Design Contradiction:

Measurement precisionVSEase of operation

Solution Approach 1:

The system enables the workpiece itself to provide its own geometric information for origin determination. The imaging apparatus captures the workpiece geometry, and the control unit automatically calculates the three-dimensional coordinates and converts them to machine coordinate system coordinates. This self-service approach eliminates the need for operator intervention and manual operation, making the process easier to perform while maintaining high accuracy.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The manual mechanical touch probe operation is replaced with an optical imaging system and automated computational process. The imaging apparatus captures images, the control unit calculates three-dimensional coordinates from these images, and automatically converts them to machine coordinate system coordinates. This substitution of mechanical manual operation with optical and computational processes significantly improves ease of operation while maintaining measurement precision.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If multiple images from different directions are captured to calculate three-dimensional coordinates, then measurement accuracy is improved, but device complexity increases

Engineering Contradiction:

Improvethree-dimensional coordinate accuracyVSAvoidimaging and coordinate calculation system complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The imaging apparatus is integrated into the machine tool system, serving dual purposes: capturing images of the workpiece for three-dimensional coordinate calculation and functioning as part of the overall machining system. The control unit that performs coordinate calculation and conversion is already present in the machine tool for other control functions, making it multi-functional rather than adding dedicated separate equipment for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS10596677B2Machine tool control system capable of obtaining workpiece origin and workpiece origin setting method

Publication Date: 2020.03.24 FANUC LTD

AI summary

A machine tool control system according to the present invention includes: a three-dimensional coordinate computing unit which calculates three-dimensional coordinates of a workpiece based on a plurality of images of the workpiece, the images being taken by the imaging apparatus from a plurality of different directions, and which calculates, from the three-dimensional coordinates, three-dimensional coordinates of a specified machining start point on the workpiece; and a coordinate converting unit which converts three-dimensional coordinates that includes the machining start point on the workpiece calculated by the three-dimensional coordinate computing unit into coordinates in the machine coordinate system for the machine tool, and which sets the converted three-dimensional coordinates of the machining start point on the workpiece, as a workpiece origin, into the machining program for the machine tool.