Automated Inertial Sensor Calibration on Repeatable Bidirectional Paths

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Inertial sensors in Global Navigation Satellite Systems (GNSS) accumulate errors over time, leading to inaccurate position measurements due to misalignment and vibration, which are not effectively addressed by existing calibration methods that rely on user-operated driving.

Innovation Solution

Automated calibration of inertial sensors by driving a machine along a prescribed path with automated steering, ensuring the machine navigates the same terrain in both directions to collect consistent pitch and roll measurements, which are then analyzed to determine and adjust for sensor biases.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If automated calibration is performed using user-operated driving, then calibration can be conducted, but the calibration reliability is low due to inconsistent terrain navigation

Engineering Contradiction:
Improvecalibration reliabilityVSAvoidposition measurement accuracy
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The system performs self-calibration by automatically comparing sensor measurements from forward and reverse trips along the same path. The machine services its own calibration needs without external intervention, using its built-in sensors and automated steering to collect and analyze data for determining sensor biases.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system uses feedback from comparing pitch and roll measurements taken during forward and reverse traversal of the same terrain to identify and correct sensor biases. The calibration process continuously refines sensor accuracy based on the discrepancy between opposing-direction measurements along the calibrated path.

Inventive Principle:
Principle #23Feedback

2Measurement precision

If inertial sensors are used to augment GPS receiver, then position data accuracy is improved, but sensor error accumulation causes drift over time

Engineering Contradiction:
Improveposition data accuracyVSAvoidsensor measurement reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system changes the operational parameters of the inertial sensors by subjecting them to controlled forward and reverse motion along a calibrated path. By varying the direction of travel and comparing sensor responses, the system identifies bias parameters that need correction and applies parameter adjustments to maintain measurement reliability.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If manual calibration methods are used, then calibration can be performed, but consistency and repeatability are poor

Engineering Contradiction:
Improvecalibration easeVSAvoidcalibration consistency
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The system replaces manual mechanical calibration operations with an automated electronic control system. The automated steering and data collection processes eliminate human variability, ensuring consistent and repeatable calibration results through systematic execution of the calibration protocol.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP3982086B1Apparatus to automate multi-point inertial sensor calibration
Publication Date: 2025.08.27 DEERE & CO
  • EP3982086B1 patent drawingFigure 1
  • EP3982086B1 patent drawingFigure 2
  • EP3982086B1 patent drawingFigure 3

AI summary

Methods, apparatus, systems and articles of manufacture are disclosed to automate multi-point inertial sensor calibration. Example apparatus disclosed herein includes a calibration path determiner to determine a calibration path for a machine to follow during calibration of the inertial sensors, the calibration path including a first point of a calibration measurement path, a second point of the calibration measurement path. The example apparatus disclosed herein includes an automated steerer to control steering of the machine on the calibration path during the calibration of the inertial sensors. The example apparatus disclosed herein includes a data recorder to record pitch and roll measurements from the inertial sensors as the machine follows the calibration path between the first point of the calibration measurement path and the second point of the calibration measurement path. The example apparatus disclosed herein includes a sensor bias determiner to determine calibration results for the inertial sensors.