Acoustic Probe TCP Tracking for Robotic Calibration

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for precisely determining the tool center point (TCP) and orientation of a robotic manipulator arm, especially with synthetic acoustic probes, are either imprecise without calibration or require tedious manual calibration, which is challenging for tools with virtual TCPs like composite material testers.

Innovation Solution

A method using acoustic probe measurements to track the TCP and orientation by determining distances and amplitudes relative to fixed reference targets, allowing the robot to align the probe's axes within its frame of reference without auxiliary tools, simplifying the calibration process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If manual calibration with reference marks is used, then measurement precision is improved, but device complexity and ease of operation deteriorate

Engineering Contradiction:

ImproveTCP and orientation determination precisionVSAvoidcalibration process complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces manual mechanical calibration operations with an automated optical measurement system. The coordinate measuring machine automatically measures reference marks and calculates TCP and orientation parameters through computational geometry, eliminating the need for manual manipulation of tools and reference marks while maintaining high measurement precision.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a coordinate measuring machine as an intermediary device between the robot system and the reference marks. This intermediary automatically performs measurement and calculation functions, simplifying the calibration process by separating the measurement task from the robot control system and providing precise geometric data through dedicated measurement equipment.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of operation

If a priori determination is used, then ease of operation is improved, but measurement precision deteriorates

Engineering Contradiction:

Improvecalibration operation simplicityVSAvoidTCP and orientation determination precision

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The patent performs preliminary measurement of reference marks and calculation of TCP and orientation parameters before actual robot operation. This preliminary action establishes accurate geometric parameters that are stored and used during robot operation, combining the benefits of advance preparation with high precision through automated measurement and calculation.

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If manual calibration is used, then measurement precision is improved, but loss of time increases

Engineering Contradiction:

ImproveTCP and orientation determination precisionVSAvoidcalibration time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent replaces time-consuming manual calibration operations with automated measurement and calculation processes. The coordinate measuring machine rapidly captures geometric data and computes TCP and orientation parameters through algorithmic processing, significantly reducing calibration time while maintaining or improving measurement precision compared to manual methods.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 method enables precise and simplified tracking of the tool's position and orientation, improving the robotic arm's ability to position the acoustic probe accurately for non-destructive testing, reducing manual intervention and calibration time.

Implementation Method 1

a first step in which the distance between the acoustic probe and a point on the surface of a point reference target occupying a fixed position is determined by means of the acoustic probe

Methodology Applied

Scientific EffectTime of flight: Time of Flight

Implementation Method 2

a second step in which amplitude and/or flight time measurements made by the acoustic probe are used in order to carry out the tracking of a fixed reference axis

Methodology Applied

Scientific EffectAcoustic reflection: Reflection

Data Source

PatentUS10201899B2Marking of the tool center and of the orientation of an acoustic probe in a reference frame, by ultrasound method

Publication Date: 2019.02.12 AIRBUS (SAS)

AI summary

A process for marking the real position and real orientation of a tool in relation to the manipulator arm of a robot. The process utilizes the amplitude measurements of acoustic signals and the flight time measurement of the acoustic waves emitted by an acoustic probe of the tool and reflected by the fixed reference elements. The position of the center of reference of the probe relative to the end of the manipulator arm is determined. The axes X and Y defining the plane of the probe along reference axes X′ and Y′ of known orientations are oriented so that the modification of the position and of the orientation of the probe in the reference frame can be defined. The displacements of the manipulator arm are managed by the controller based on the position of the probe in relation to the manipulator arm and the reference orientation of the probe.