Multi-Camera Optical Mirror Position and Orientation Tracking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods fail to accurately determine the positions and orientations of mirrors in a field of view using a single camera setup, making it difficult to spatially resolve vorticity of fluid flows or deformations of surfaces, as the orientation data from one camera cannot be reliably allocated to position data from another camera.

Innovation Solution

A method involving three cameras – one in the image plane, one in the focal plane, and another in an intermediate plane – where all cameras take synchronized pictures, allowing the light intensity distribution from the intermediate plane to correlate positions and orientations of mirrors, enabling precise tracking of mirror positions and orientations within the field of view.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single camera is used to determine mirror positions and orientations, then the device complexity is reduced, but the measurement precision deteriorates because orientation data cannot be reliably allocated to position data

Engineering Contradiction:
Improvecamera setupVSAvoidmirror position and orientation determination
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The measurement task is segmented into two separate functions: one camera (first camera) determines mirror positions by imaging the field of view, while another camera (second camera) determines mirror orientations by detecting reflected light directions. This segmentation allows each camera to specialize in one measurement aspect, resolving the allocation problem between position and orientation data.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A third camera arranged in an intermediate plane serves as an intermediary that captures images containing both position and orientation information of mirrors. This intermediate camera provides the correlation data needed to link position measurements from the first camera with orientation measurements from the second camera, enabling accurate spatially resolved determination.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If multiple cameras are used to determine both positions and orientations of mirrors, then the measurement precision is improved, but the device complexity increases

Engineering Contradiction:
Improvemirror position and orientation determinationVSAvoidcamera setup
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The optical system is designed with multi-functionality where the same optical path and illumination system serve multiple cameras simultaneously. The first, second, and third cameras share the optical infrastructure, allowing the system to perform multiple measurement functions (position determination, orientation determination, and correlation) without proportionally increasing overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The third camera is positioned in an intermediate plane between the first camera's image plane and the second camera's focal plane. This dimensional arrangement in optical space allows the intermediate camera to capture information that bridges the gap between position and orientation measurements, providing correlation data without requiring a completely separate measurement system.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Reliability

If synchronized pictures are taken with multiple cameras, then the reliability of correlating position and orientation data is improved, but the loss of time increases due to complex coordination

Engineering Contradiction:
Improvedata correlationVSAvoidsynchronization coordination
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system uses the third camera's intermediate plane images as feedback to establish the correlation between position and orientation data. By capturing images at the intermediate plane that contain both position and orientation information, the system creates a reference framework that enables reliable data association without requiring complex real-time synchronization coordination between all cameras.

Inventive Principle:
Principle #23Feedback

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 allows for accurate spatially resolved determination of mirror positions and orientations, enabling effective tracking of fluid flow vorticity and surface deformations, even with multiple mirrors, by correlating light spots across multiple images taken simultaneously or at subsequent points in time.

Implementation Method 1

A second camera is arranged in a focal plane of the objective; and a third camera is arranged in an intermediate plane located at a distance to both the image plane and the focal plane of the objective

Methodology Applied
Scientific EffectFocusing: Focusing

Implementation Method 2

The field of view is illuminated with parallel light rays... light intensity distribution of the picture taken with the first camera essentially or even completely depends on the positions of the mirrors in the field of view reflecting the parallel light rays

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 3

the light intensity distribution of the image taken with the second camera essentially or even completely depends on the direction of the parallel or almost-no-divergence light rays reflected by the mirrors... light intensity distribution of the picture taken with the first camera essentially or even completely depends on the positions of the mirrors

Methodology Applied
Scientific EffectLight propagation: Light

Data Source

PatentEP3015817B1Optical method of and apparatus for determining positions and orientations of a plurality of mirrors in the field of view of an objective lens
Publication Date: 2019.12.18 MAX PLANCK GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN EV
  • EP3015817B1 patent drawingFigure 1~2
  • EP3015817B1 patent drawingFigure 3

AI summary

For determining positions and orientations of a plurality of mirrors (1 to 4) in an field of view (5) of an objective (6), the field of view (5) is illuminated with parallel light rays (15). A first camera (19) is arranged in an image plane (21) onto which the objective (6) images the field of view (5). A second camera (17) is arranged in a focal plane (22) of the objective (6), and a third camera (18) is arranged in an intermediate plane (23) located at distances to both the image plane (21) and the focal plane (22) of the objective (6). At a same point in time a first picture, a second picture and a third picture are taken with the first, the second and the third camera (19, 17, 18), respectively. The positions of the mirrors (4) in the field of view (5) are determined from positions of light spots (25) in the first picture; the orientations of the mirrors (1 to 4) in the field of view (5) are determined from positions of light spots (24) in the second picture; and which of the orientations belongs to which of the positions of the mirrors (1 to 4) in the field of view (5) are determined by correlating positions of light spots (26) in the third picture with both the light spots (25) in the first picture and the light spots (24) in the second picture.