3D Mapping Error Compensation via Geometric Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing 3D optical mapping techniques face errors due to distortions and misalignments in the projection and detection of patterns, leading to inaccuracies in depth coordinate calculations.
Innovation Solution
A method and apparatus that corrects for these errors by computing a geometrical correction factor based on measured offsets of pattern elements, applying it to find corrected offsets, and calculating depth coordinates, which includes correcting for distortions, misalignments, and changes in wavelength and focal length using a processor and look-up tables.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If pattern projection and detection are performed for 3D mapping, then depth coordinate information can be obtained, but measurement precision deteriorates due to distortions and misalignments
Solution Approach 1:
The system performs preliminary calibration by projecting a reference pattern onto a reference surface and detecting it with the detector array before actual 3D mapping. This preliminary action establishes reference data that accounts for system-specific distortions and misalignments, which are then used to correct measurements during operational mapping, thereby improving depth coordinate accuracy while maintaining reliability
Solution Approach 2:
The system uses feedback from the detected pattern positions compared against reference pattern positions to identify offsets and distortions. This feedback loop allows the system to continuously correct for misalignments and distortions by comparing actual measurements with expected values, thereby maintaining high measurement precision and reliability
2Measurement precision
If geometric correction factors are computed and applied to correct offsets, then measurement precision improves, but device complexity increases
Solution Approach 1:
The system replaces complex mechanical alignment and correction mechanisms with computational methods. Instead of using additional mechanical components to physically correct for distortions and misalignments, the invention uses software-based geometric correction factors computed from offset measurements, thereby improving precision while avoiding increased hardware complexity
Solution Approach 2:
The system changes parameters by computing correction factors based on measured offsets and applying these to adjust the detected pattern positions. This parameter transformation approach allows the system to correct for distortions and misalignments through mathematical adjustments rather than physical modifications, improving measurement accuracy without adding device complexity
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 approach enhances the accuracy of 3D mapping by compensating for various distortions and misalignments, resulting in improved depth coordinate calculations and more precise 3D object profiling.
Implementation Method 1
illuminating the object from a light source so as to project a pattern onto the object
Implementation Method 2
capturing an image of the pattern on the object using an array of detector elements
Data Source
AI summary
A method for forming a three-dimensional (3D) map of an object, including illuminating the object from a light source so as to project a pattern onto the object, capturing an image of the pattern using an array of detector elements, and processing the captured image so as to measure respective offsets of elements of the pattern in the captured image relative to a reference pattern, the offsets including at least a first offset of a first element of the pattern and a second offset of a second element of the pattern, measured respectively in first and second, mutually-perpendicular directions in a plane of the array. The method further includes computing a correction factor in response to the first offset, applying the correction factor to the second offset so as to find a corrected offset, and computing depth coordinates of the object in response to the corrected offset.