Accelerometer Calibration via Coordinate Transformation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing accelerometer systems in vehicles require skilled installers and are time-consuming to align, and they can become misaligned over time due to vehicle impacts or mishandling, making it difficult to detect and correct misalignments in the field.
Innovation Solution
A method for automating the alignment of tri-axial accelerometers using coordinate transformations to calibrate the sensor axes with the vehicle's Cartesian coordinate system, allowing for minimal human intervention and adaptive alignment in the field, utilizing devices like the WebTech Wireless Locator Series with GPS and wireless modem technology.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If manual installation and physical alignment of accelerometer axes with vehicle axes is performed, then alignment precision is improved, but installer skill requirement and installation time increase
Solution Approach 1:
The patent replaces manual mechanical alignment procedures with an automated computational method. Instead of physically aligning accelerometer axes with vehicle axes through skilled manual installation, the system uses computer-based coordinate transformations to calculate and correct alignment, eliminating the need for skilled installers while maintaining precision.
Solution Approach 2:
The patent changes the alignment approach from physical parameter adjustment to computational parameter transformation. By using coordinate transformations with calculated rotation matrices, the system adjusts the mathematical representation of accelerometer data to account for misalignment, replacing manual physical alignment with computational parameter correction.
2Manufacturing precision
If manual installation and physical alignment of accelerometer axes with vehicle axes is performed, then alignment precision is improved, but installation time increases
Solution Approach 1:
The patent replaces time-consuming manual mechanical alignment procedures with rapid computational methods. The coordinate transformation calculation is performed automatically by a computer, dramatically reducing installation time from manual procedures to automated computation while maintaining alignment precision.
Solution Approach 2:
The patent performs alignment calculations and coordinate transformation matrix generation as preliminary actions during installation. By pre-calculating the rotation matrices and transformation parameters based on known accelerometer orientation relative to the vehicle, the system eliminates time-consuming trial-and-error alignment procedures.
3Adaptability or versatility
If accelerometer is deployed in the field, then operational flexibility is improved, but misalignment detection and correction difficulty increases
Solution Approach 1:
The patent implements feedback mechanisms that continuously monitor accelerometer performance and detect misalignment conditions in the field. The system uses feedback from operational data to identify when recalibration is needed, enabling automatic detection and correction of misalignment without requiring skilled installers or specialized equipment.
Solution Approach 2:
The patent enables the accelerometer system to self-diagnose and self-correct misalignment issues in the field. Through automated coordinate transformation calculations and built-in calibration capabilities, the system performs its own alignment adjustments without requiring external skilled intervention, maintaining operational flexibility while simplifying misalignment correction.
4Ease of operation
If automated coordinate transformation calibration is implemented, then installer skill requirement is reduced, but measurement precision may be compromised
Solution Approach 1:
The patent replaces manual mechanical alignment with sophisticated computational methods that maintain or improve precision. The coordinate transformation algorithm uses mathematical models to calculate exact rotation matrices, providing sub-pixel alignment precision that exceeds manual methods while requiring no skilled installation.
Solution Approach 2:
The patent transforms the alignment problem from physical parameter adjustment to computational parameter calculation. By using precise mathematical models and coordinate transformations, the system achieves high measurement precision through computational accuracy rather than manual skill, eliminating the trade-off between ease of installation and measurement precision.
Data Source
AI summary
An accelerometer sensor equipped device uses GPS and known alignment data to determine the alignment of the accelerometer sub-system when the vehicle is stationary and in motion. The alignment data is determined from known surface information, measured GPS velocity, and measured GPS Heading.