Least-Square-Method-Based Optimal Laser Spots Acquisition and Position in Cooperative Target Measurement

The relative positioning precisions of coordinate points is an important indicator that affects the final accuracy in the visual measurement system of space cooperative targets. Many factors, such as measurement methods, environmental conditions, data processing principles and equipment parameters,...

Full description

Saved in:
Bibliographic Details
Published in:Sensors (Basel, Switzerland) Switzerland), 2022-07, Vol.22 (14), p.5110
Main Authors: Li, Kai, Yuan, Feng, Hu, Yinghui, Du, Yongbin, Chen, Wei, Lan, Chunyun
Format: Article
Language:English
Subjects:
Accuracy
Algorithms
Cameras
Centroids
Charge coupled devices
cooperative target
Coordinate transformations
Data processing
diode supply current
Equations of state
Experiments
exposure time
laser-projected spot
Lasers
least square method
Light emitting diodes
Measurement methods
Nonlinear equations
Optimization
Position measurement
Semiconductor lasers
Simulation
Target acquisition
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The relative positioning precisions of coordinate points is an important indicator that affects the final accuracy in the visual measurement system of space cooperative targets. Many factors, such as measurement methods, environmental conditions, data processing principles and equipment parameters, are supposed to influence the cooperative target’s acquisition and determine the precision of the cooperative target’s position in a ground simulation experiment with laser projected spots on parallel screens. To overcome the precision insufficiencies of cooperative target measurement, the factors of the laser diode supply current and charge couple device (CCD) camera exposure time are studied in this article. On the hypothesis of the optimal experimental conditions, the state equations under the image coordinates’ system that describe the laser spot position’s variation are established. The novel optimizing method is proposed by taking laser spot position as state variables, diode supply current and exposure time as controllable variables, calculating the optimal controllable variables through intersecting the focal spot centroid line and the 3-D surface, and avoiding the inconvenience of solving nonlinear equations. The experiment based on the new algorithm shows that the optimal solution can guarantee the focal spot’s variation range in 5–10 pixels under image coordinates’ system equivalent to the space with a 3 m distance and 0.6–1.2 mm positioning accuracy.
ISSN:1424-8220
1424-8220
DOI:10.3390/s22145110