Depth Camera Self-Calibration via Fiducial Projection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Stereo depth camera systems face calibration challenges due to relative movements between components caused by temperature changes, drops, or bending, requiring recalibration but often become impractical without a reference chart.
Innovation Solution
The system uses an IR projector to display invisible fiducial images, which are captured by cameras to recalculate calibration coefficients, allowing for automatic recalibration without external patterns or user intervention.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If recalibration is performed using a special reference chart, then measurement precision is restored, but ease of operation deteriorates due to requiring external equipment and user intervention
Solution Approach 1:
The system performs self-calibration by projecting fiducial patterns and capturing images using its own integrated camera, eliminating the need for external reference charts or user intervention. The processor automatically determines calibration coefficients from the captured fiducial pattern images, enabling the device to recalibrate itself in situ.
Solution Approach 2:
Fiducial projection patterns serve as an intermediary medium that enables calibration without requiring physical contact with external reference objects. These patterns are projected onto the scene and captured by the camera, providing the necessary reference information for calculating calibration coefficients.
2Adaptability or versatility
If the system is made portable and flexible, then adaptability improves, but reliability deteriorates due to component movement from drops, bending, or temperature changes
Solution Approach 1:
The system transitions from static calibration (performed once during assembly) to dynamic calibration (can be performed anytime in situ). The ability to recalibrate at any time allows the system to adapt to changes in component relationships caused by portability-related events such as drops, bending, or temperature variations.
Solution Approach 2:
The system performs preliminary calibration during assembly, and then enables on-demand recalibration whenever needed. This preliminary action establishes the baseline calibration, while the capability for subsequent recalibration ensures continued reliability despite physical changes.
3Manufacturing precision
If initial calibration is performed during assembly, then manufacturing precision is achieved, but ease of repair deteriorates when recalibration is needed after component movement
Solution Approach 1:
The patent replaces the mechanical requirement of physical reference charts with an optical/electronic solution. Fiducial patterns are projected and captured digitally, allowing calibration coefficients to be determined through image processing rather than mechanical measurement, enabling recalibration without disassembly or special tools.
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
Enables accurate depth reconstruction by recalibrating the camera system's components automatically, maintaining precision even after physical changes, without the need for special charts or user-generated patterns.
Implementation Method 1
activates an infrared light source of the depth camera system for displaying one or more invisible fiducial projection patterns
Data Source
AI summary
A method and apparatus for performing inbuilt calibration of camera system that performs three-dimensional measurements and depth reconstruction are described. In one embodiment, the method includes displaying, using a projector of a capture device, a fiducial projection pattern in response to calibration of the capture device. The method may also include capturing, with a camera of the capture, an image of the fiducial projection pattern. The method may also include determining calibration coefficient values indicative of relative physical relationships of one or more components of the depth camera system based on analysis of the captured image of the fiducial projection pattern.