Temperature Compensation Method for Mechanical Base of 3D-Structured Light Scanners

The effect of temperature on three-dimensional (3D) structured light scanners is a very complex issue that, under some conditions, can lead to significant deterioration of performed measurements. In this paper, we present the results of several studies concerning the effect of temperature on the mechanical base of 3D-structured light scanners. We also propose a software compensation method suitable for implementation in any existing scanner. The most significant advantage of the described method is the fact that it does not require any specialized artifact or any additional equipment, nor access to the thermal chamber. It uses a simulation of mechanical base thermal deformations and a virtual 3D measurement environment that allows for conducting virtual measurements. The results from the verification experiments show that the developed method can extend the range of temperatures in which 3D-structured light scanners can perform valid measurements by more than six-fold.

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Temperature Compensation Method for Raster Projectors Used in 3D Structured Light Scanners

Sensors ◽

10.3390/s20205778 ◽

2020 ◽

Vol 20 (20) ◽

pp. 5778

Author(s):

Marcin Adamczyk

Keyword(s):

Thermal Effects ◽

Temperature Compensation ◽

Measurement Method ◽

Environmental Temperature ◽

Structured Light ◽

Three Dimensional ◽

Compensation Method ◽

Effect Of Temperature ◽

Significant Deterioration ◽

Effects Of Temperature

Raster projectors are commonly used in many various measurement applications where active lighting is required, such as in three-dimensional structured light scanners. The effect of temperature on the raster projector, in some conditions, can lead to significant deterioration of the measurements performed with such a scanner. In this paper, the outcomes of several experiments concerning the effects of temperature on raster projectors are presented. The described research is focused on the thermal deformations of projected images caused by common thermal effects observed in projectors: those caused by the warming-up process and changes in ambient environmental temperature. A software compensation method is also presented. It is suitable for implementation in any existing measurement method that uses raster projectors. The results of performed verification experiments show that the developed compensation method can decrease the thermal drift of the projected images by up to 14 times in the ambient temperature range 14–42 °C.

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Temperature Compensation Method for Digital Cameras in 2D and 3D Measurement Applications

Sensors ◽

10.3390/s18113685 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3685 ◽

Cited By ~ 4

Author(s):

Marcin Adamczyk ◽

Paweł Liberadzki ◽

Robert Sitnik

Keyword(s):

Temperature Compensation ◽

Three Dimensional ◽

Compensation Method ◽

Effect Of Temperature ◽

Calibration Model ◽

Digital Cameras ◽

Compensation Model ◽

Camera Design ◽

Compensation Approach ◽

2D And 3D

This paper presents the results of several studies concerning the effect of temperature on digital cameras. Experiments were performed using three different camera models. The presented results conclusively demonstrate that the typical camera design does not adequately take into account the effect of temperature variation on the device’s performance. In this regard, a modified camera design is proposed that exhibits a highly predictable behavior under varying ambient temperature and facilitates thermal compensation. A novel temperature compensation method is also proposed. This compensation model can be applied in almost every existing camera application, as it is compatible with every camera calibration model. A two-dimensional (2D) and three-dimensional (3D) application of the proposed compensation model is also described. The results of the application of the proposed compensation approach are presented herein.

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Projector calibration with error surface compensation method in the structured light three-dimensional measurement system

Optical Engineering ◽

10.1117/1.oe.52.4.043602 ◽

2013 ◽

Vol 52 (4) ◽

pp. 043602 ◽

Cited By ~ 11

Author(s):

Junhui Huang ◽

Zhao Wang ◽

Jianmin Gao ◽

Qi Xue

Keyword(s):

Measurement System ◽

Structured Light ◽

Three Dimensional ◽

Compensation Method ◽

Dimensional Measurement ◽

Error Surface ◽

Projector Calibration ◽

Three Dimensional Measurement

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Effect of temperature on calibration quality of structured-light three-dimensional scanners

Applied Optics ◽

10.1364/ao.53.005154 ◽

2014 ◽

Vol 53 (23) ◽

pp. 5154 ◽

Cited By ~ 6

Author(s):

M. Adamczyk ◽

M. Kamiński ◽

R. Sitnik ◽

A. Bogdan ◽

M. Karaszewski

Keyword(s):

Structured Light ◽

Three Dimensional ◽

Effect Of Temperature

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Calibration Algorithm for Error Screening Based on Line Structured Light

International Journal of Artificial Intelligence Tools ◽

10.1142/s0218213020400138 ◽

2020 ◽

Vol 29 (07n08) ◽

pp. 2040013

Author(s):

Baolong Liu ◽

Ruixia Wu ◽

Yu Liu

Keyword(s):

Structured Light ◽

Three Dimensional ◽

Small Error ◽

Calibration Error ◽

3D Measurement ◽

Screening Model ◽

Calibration Algorithm ◽

On Line ◽

3D Measurement System ◽

Compensation Function

The 3D measurement system based on line-structured light uses a camera to capture laser stripes due to changing in the shape of an object, and uses the acquired pixel coordinates for 3D reconstruction. System calibration is an important step in 3D measurement. The current camera calibration algorithm research mainly focuses on improving the algorithm itself, and there is less research on the influence of external factors. This paper proposes a coplanar hybrid calibration algorithm based on the error screening model by combining the error screening model, mathematical model and neural network model. It is mainly divided into two steps. The first step is to use the radial array constraint calibration algorithm based on the error screening model to solve the camera’s internal and external parameters. The second step uses the camera internal and external parameters obtained in the first step to convert the pixel coordinates into real three-dimensional coordinates, and compares the calculated three-dimensional coordinates with the actual coordinates. Using machine learning to establish a compensation network, get a compensation function, and use the resulting 3D world coordinates to perform point cloud stitching. Experiments show that compared with the traditional calibration algorithm, the calibration algorithm has a small error and reduces the calibration error by about 6.5%.

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A Topology-Based Stereo Matching Method for One Shot 3D Measurement Using Coded Spot-Array Structured Light

Sensors ◽

10.3390/s21196444 ◽

2021 ◽

Vol 21 (19) ◽

pp. 6444

Author(s):

Junhui Mei ◽

Xiao Yang ◽

Zhenxin Wang ◽

Xiaobo Chen ◽

Juntong Xi

Keyword(s):

Stereo Matching ◽

Interpolation Method ◽

Structured Light ◽

Three Dimensional ◽

Single Shot ◽

3D Measurement ◽

Matching Method ◽

Single Pattern ◽

Ring Spot ◽

Spot Array

In this paper, a topology-based stereo matching method for 3D measurement using a single pattern of coded spot-array structured light is proposed. The pattern of spot array is designed with a central reference ring spot, and each spot in the pattern can be uniquely coded with the row and column indexes according to the predefined topological search path. A method using rectangle templates to find the encoded spots in the captured images is proposed in the case where coding spots are missing, and an interpolation method is also proposed for rebuilding the missing spots. Experimental results demonstrate that the proposed technique could exactly and uniquely decode each spot and establish the stereo matching relation successfully, which can be used to obtain three-dimensional (3D) reconstruction with a single-shot method.

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A Reference Matching-Based Temperature Compensation Method for Ultrasonic Guided Wave Signals

Sensors ◽

10.3390/s19235174 ◽

2019 ◽

Vol 19 (23) ◽

pp. 5174

Author(s):

Geng Wang ◽

Yuhang Wang ◽

Hu Sun ◽

Bingrong Miao ◽

Yishou Wang

Keyword(s):

Temperature Compensation ◽

Guided Wave ◽

Compensation Method ◽

Effect Of Temperature ◽

Influence Coefficient ◽

Temperature Range ◽

Ultrasonic Guided Wave ◽

Reference Signals ◽

Different Temperatures ◽

The Relationship

The ultrasonic guided wave-based structural damage diagnosis method has broad application prospects in different fields. However, some environmental factors such as temperature and loads will significantly affect the monitoring results. In this paper, a reference matching-based temperature compensation for ultrasonic guided wave signals is proposed to eliminate the effect of temperature. Firstly, the guided wave signals measured at different temperatures are used as reference signals to establish the relationship between the features of the reference signals and temperature. Then the matching algorithm based on Gabor function is used to establish the relationship between the amplitude influence coefficient obtained by the reference signal and the corresponding temperature. Finally, through these two relationships, the values of the phase and amplitude influence coefficients of the guided wave signals at other temperatures are obtained in a way of interpolation in order to reconstruct the compensation signals at the temperature. The effect of temperature on the amplitude and phase of the guided wave signal is eliminated. The proposed temperature compensation method is featured such that the compensation performance can be improved by multiple iteration compensation of the residual signal. The ultrasonic guided wave test results at different temperatures show that the first iterative compensation of the proposed method can achieve compensation within the temperature range greater than 7 °C, and the compensation within the temperature range greater than 18 °C can be achieved after three iterations.

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Structured-light 3D scanning of exhibited historical clothing—a first-ever methodical trial and its results

Heritage Science ◽

10.1186/s40494-021-00544-x ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Jerzy Montusiewicz ◽

Marek Miłosz ◽

Jacek Kęsik ◽

Kamil Żyła

Keyword(s):

Cultural Heritage ◽

Information Technologies ◽

Structured Light ◽

Three Dimensional ◽

3D Models ◽

3D Scanning ◽

Dimensional Representation ◽

3D Scanner ◽

Three Dimensional Representation ◽

3D Scanners

AbstractHistorical costumes are part of cultural heritage. Unlike architectural monuments, they are very fragile, which exacerbates the problems of their protection and popularisation. A big help in this can be the digitisation of their appearance, preferably using modern techniques of three-dimensional representation (3D). The article presents the results of the search for examples and methodologies of implementing 3D scanning of exhibited historical clothes as well as the attendant problems. From a review of scientific literature it turns out that so far practically no one in the world has made any methodical attempts at scanning historical clothes using structured-light 3D scanners (SLS) and developing an appropriate methodology. The vast majority of methods for creating 3D models of clothes used photogrammetry and 3D modelling software. Therefore, an innovative approach was proposed to the problem of creating 3D models of exhibited historical clothes through their digitalisation by means of a 3D scanner using structural light technology. A proposal for the methodology of this process and concrete examples of its implementation and results are presented. The problems related to the scanning of 3D historical clothes are also described, as well as a proposal how to solve them or minimise their impact. The implementation of the methodology is presented on the example of scanning elements of the Emir of Bukhara's costume (Uzbekistan) from the end of the nineteenth century, consisting of the gown, turban and shoes. Moreover, the way of using 3D models and information technologies to popularise cultural heritage in the space of digital resources is also discussed.

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Combining 3D Structured Light Imaging and Spine X-ray Data Improves Visualization of the Spinous Lines in the Scoliotic Spine

Applied Sciences ◽

10.3390/app11010301 ◽

2020 ◽

Vol 11 (1) ◽

pp. 301

Author(s):

Sławomir Paśko ◽

Wojciech Glinkowski

Keyword(s):

Radiation Exposure ◽

Surface Topography ◽

Structured Light ◽

Spinous Process ◽

Three Dimensional ◽

Diagnostic System ◽

Measurement Tool ◽

Adequate Treatment ◽

X Ray ◽

Spinous Processes

Scoliosis is a three-dimensional trunk and spinal deformity. Patient evaluation is essential for the decision-making process and determines the selection of specific and adequate treatment. The diagnosis requires a radiological evaluation that exposes patients to radiation. This exposure reaches hazardous levels when numerous, repetitive radiographic studies are required for diagnostics, monitoring, and treatment. Technological improvements in radiographic devices have significantly reduced radiation exposure, but the risk for patients remains. Optical three-dimensional surface topography (3D ST) measurement systems that use surface topography (ST) to screen, diagnose, and monitor scoliosis are safer alternatives to radiography. The study aimed to show that the combination of plain X-ray and 3D ST scans allows for an approximate presentation of the vertebral column spinous processes line in space to determine the shape of the spine’s deformity in scoliosis patients. Twelve patients diagnosed with scoliosis, aged 13.1 ± 4.5 years (range: 9 to 20 years) (mean: Cobb angle 17.8°, SD: ±9.5°) were enrolled in the study. Patients were diagnosed using full-spine X-ray and whole torso 3D ST. The novel three-dimensional assessment of the spinous process lines by merging 3D ST and X-ray data in patients with scoliosis was implemented. The method’s expected uncertainty is less than 5 mm, which is better than the norm for a standard measurement tool. The presented accuracy level is considered adequate; the proposed solution is accurate enough to monitor the changes in the shape of scoliosis’s spinous processes line. The proposed method allows for a relatively precise calculation of the spinous process lines based on a three-dimensional point cloud obtained with a four-directional, three-dimensional structured light diagnostic system and a single X-ray image. The method may help reduce patients’ total radiation exposure and avoid one X-ray in the sagittal projection if biplanar radiograms are required for reconstructing the three-dimensional line of the spinous processes line.

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