scholarly journals A Novel Calibration Method of Articulated Laser Sensor for Trans-Scale 3D Measurement

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1083 ◽  
Author(s):  
Jiehu Kang ◽  
Bin Wu ◽  
Xiaodeng Duan ◽  
Ting Xue
Keyword(s):  
Measurement Instrument ◽  
Calibration Method ◽  
High Accuracy ◽  
Industrial Applications ◽  
Laser Beams ◽  
Laser Sensor ◽  
3D Measurement ◽  
System Parameters ◽  
Laser Sensing ◽  
Processing Techniques

The articulated laser sensor is a new kind of trans-scale and non-contact measurement instrument in regular-size space and industrial applications. These sensors overcome many deficiencies and application limitations of traditional measurement methods. The articulated laser sensor consists of two articulated laser sensing modules, and each module is made up of two rotary tables and one collimated laser. The three axes represent a non-orthogonal shaft architecture. The calibration method of system parameters for traditional instruments is no longer suitable. A novel high-accuracy calibration method of an articulated laser sensor for trans-scale 3D measurement is proposed. Based on perspective projection models and image processing techniques, the calibration method of the laser beam is the key innovative aspect of this study and is introduced in detail. The experimental results show that a maximum distance error of 0.05 mm was detected with the articulated laser sensor. We demonstrate that the proposed high-accuracy calibration method is feasible and effective, particularly for the calibration of laser beams.

Self-Calibration of the Stereo Vision System of the Chang'e-4 Lunar Rover Based on the Points and Lines Combined Adjustment

2020 ◽  
Vol 86 (3) ◽  
pp. 169-176
Author(s):  
Shuo Zhang ◽  
Yang Jia ◽  
Song Peng ◽  
Bo Wen ◽  
Youqing Ma ◽  
...  
Keyword(s):  
Stereo Vision ◽  
Vision System ◽  
Measurement Instrument ◽  
Calibration Method ◽  
High Accuracy ◽  
Calibration Model ◽  
Lunar Rover ◽  
Self Calibration ◽  
Stereo Vision System ◽  
Laboratory Calibration

The stereo vision system is the special engineering measurement instrument of the Chang'e-4 lunar rover. It is composed of the Navigation Camera (NavCam) and the Mast Mechanism (MasMec). An improved self-calibration method for the stereo vision system of the Chang'e-4 lunar rover is proposed. The method consists of two parts: the NavCam's self-calibration and the MasMec's self-calibration. A combined adjustment based on the points and lines is proposed. The baseline constraint of the NavCam is considered. The self-calibration model of the MasMec is established based on the product-of-exponentials formula. Finally, the premission laboratory calibration and the on-site calibration are carried out. The laboratory calibration shows that the proposed approach has high accuracy. The checkpoint with a distance of about 2.7 m to the left NavCam has a point error of about 4 mm. Finally, the proposed approach is applied in the on-site calibration.

A Design of High-Accuracy Displacement Measurement Instrument from Principles of Optics

2012 ◽  
Vol 170-173 ◽  
pp. 2924-2928
Author(s):  
Sheng Biao Chen ◽  
Yun Zhi Tan
Keyword(s):  
Measurement Instrument ◽  
High Accuracy ◽  
Mechanical Tests ◽  
Total Reflection ◽  
Displacement Measurement ◽  
New Method ◽  
Water Volume ◽  
Water Drainage ◽  
Accuracy Of Measurement ◽  
Better Than

In order to measure the water drainage volume in soil mechanical tests accurately, it develop a new method which is based on principles of optics. And from both physical and mathematic aspects, it deduces the mathematic relationship between micro change in displacement and the increment projected on screen. The result shows that total reflection condition is better than refraction condition. What’s more, the screen could show the water volume micro variation clearly, so it can improve the accuracy of measurement.

A study on encoding-based oracle bone script recognition

2020 ◽  
Vol 4 (4) ◽  
pp. 281-290
Author(s):  
Tingzhu Chen ◽  
Yaoyao Qian ◽  
Jingyu Pei ◽  
Shaoteng Wu ◽  
Jiang Wu ◽  
...  
Keyword(s):  
General Public ◽  
Expert Knowledge ◽  
Recognition Accuracy ◽  
Fundamental Problem ◽  
High Accuracy ◽  
Time Range ◽  
Accuracy Rate ◽  
Script Recognition ◽  
Processing Techniques ◽  
Accuracy Speed

Oracle bone script recognition (OBSR) has been a fundamental problem in research on oracle bone scripts for decades. Despite being intensively studied, existing OBSR methods are still subject to limitations regarding recognition accuracy, speed and robustness. Furthermore, the dependency of these methods on expert knowledge hinders the adoption of OBSR systems by the general public and also discourages social outreach of research outputs. Addressing these issues, this study proposes an encoding-based OBSR system that applies image pre-processing techniques to encode oracle images into small matrices and recognize oracle characters in the encoding space. We tested our methods on a collection of oracle bones from the Yin Ruins in XiaoTun village, and achieved a high accuracy rate of 99% within a time range of milliseconds.

A robot hand-eye calibration method of line laser sensor based on 3D reconstruction

2021 ◽  
Vol 71 ◽  
pp. 102136
Author(s):  
Mingyang Li ◽  
Zhijiang Du ◽  
Xiaoxing Ma ◽  
Wei Dong ◽  
Yongzhuo Gao
Keyword(s):  
3D Reconstruction ◽  
Calibration Method ◽  
Laser Sensor ◽  
Robot Hand

scholarly journals High-Accuracy Calibration Based on Linearity Adjustment for Eddy Current Displacement Sensor

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2842 ◽  
Author(s):  
Wei Liu ◽  
Bing Liang ◽  
Zhenyuan Jia ◽  
Di Feng ◽  
Xintong Jiang ◽  
...  
Keyword(s):  
Eddy Current ◽  
Measurement Accuracy ◽  
Characteristic Curve ◽  
Calibration Method ◽  
High Accuracy ◽  
Output Characteristic ◽  
Displacement Sensor ◽  
Support Vector ◽  
Displacement Sensors ◽  
Calibration Accuracy

High precision position control is essential in the process of parts manufacturing and assembling, where eddy current displacement sensors (ECDSs) are widely used owing to the advantages of non-contact sensing, compact volume, and resistance to harsh conditions. To solve the nonlinear characteristics of the sensors, a high-accuracy calibration method based on linearity adjustment is proposed for ECDSs in this paper, which markedly improves the calibration accuracy and then the measurement accuracy. After matching the displacement value and the output voltage of the sensors, firstly, the sensitivity is adjusted according to the specified output range. Then, the weighted support vector adjustment models with the optimal weight of the zero-scale, mid-scale and full-scale are established respectively to cyclically adjust the linearity of the output characteristic curve. Finally, the final linearity adjustment model is obtained, and both the calibration accuracy and precision are verified by the established calibration system. Experimental results show that the linearity of the output characteristic curve of ECDS adjusted by the calibration method reaches over 99.9%, increasing by 1.9–5.0% more than the one of the original. In addition, the measurement accuracy improves from 11–25 μ m to 1–10 μ m in the range of 6mm, which provides a reliable guarantee for high accuracy displacement measurement.

scholarly journals Smart Dye Inspection System in Textile Industry

2020 ◽  
Vol 8 (6) ◽  
pp. 5061-5063
Keyword(s):  
Image Processing ◽  
Reference Material ◽  
Textile Industry ◽  
High Accuracy ◽  
Inspection System ◽  
Manual Operation ◽  
Image Processing Techniques ◽  
Manual Inspection ◽  
Processing Techniques

Inspection on the dyed material in the textile industry is facing a challenging task owing to the accurate measurement of the dye concentration added. Currently manual inspection is done. It consumes more time and less accurate. The proposed work provides a solution to above problem. The image of reference material (cloth) is captured and the features are extracted using image processing techniques. The color concentration of both the reference material and the test fabric is compared. If the dye concentration of the test fabric matches with the reference material, then it is a perfect dyed cloth whereas for mismatched samples, the concentration is to be adjusted is displayed. This smart dyeing inspection system reduces the manual operation and saves time and results in high accuracy.

scholarly journals High Accuracy Measurement of Total Losses in Fractional Horsepower Induction Motors

2015 ◽  
Vol 1 (2) ◽  
pp. 13
Author(s):  
Azzeddine Ferrah ◽  
Mounir Bouzguenda ◽  
Jehad M. Al-Khalaf Bani Younis
Keyword(s):  
Single Phase ◽  
Induction Motors ◽  
Data Acquisition System ◽  
High Accuracy ◽  
Industrial Applications ◽  
Motor Speed ◽  
Accuracy Measurement ◽  
Three Phase ◽  
Better Than ◽  
High Accuracy Measurement

Large and small single-phase and three-phase induction motors are commonly used in industrial applications. The present work represents an attempt towards the design of a high accuracy system for the measurement of fractional horsepower (FHP) induction motor losses and efficiency. The calorimeter designed and built is capable of measuring heat losses of up to 1 kW with an overall accuracy better than 3%. During all tests, ambient temperature, humidity, motor speed and motor frame temperature were recorded using precise digital instruments. The inlet, outlet temperatures and resulting losses were recorded automatically using a high accuracy 12-bit data acquisition system. The preliminary results obtained demonstrate the suitability of the designed calorimeter for the accurate measurement of losses in FHP induction motors.

scholarly journals Depth image correction for intel realsense depth camera

2020 ◽  
Vol 19 (2) ◽  
pp. 1021
Author(s):  
Hyun Jun Park ◽  
Kwang Baek Kim
Keyword(s):  
Image Processing ◽  
Infrared Radiation ◽  
Infrared Camera ◽  
High Accuracy ◽  
Depth Image ◽  
Depth Information ◽  
Depth Camera ◽  
Image Correction ◽  
Image Processing Techniques ◽  
Processing Techniques

<p><span>Intel RealSense depth camera provides depth image using infrared projector and infrared camera. Using infrared radiation makes it possible to measure the depth with high accuracy, but the shadow of infrared radiation makes depth unmeasured regions. Intel RealSense SDK provides a postprocessing algorithm to correct it. However, this algorithm is not enough to be used and needs to be improved. Therefore, we propose a method to correct the depth image using image processing techniques. The proposed method corrects the depth using the adjacent depth information. Experimental results showed that the proposed method corrects the depth image more accurately than the Intel RealSense SDK.</span></p>

scholarly journals Insecticide’s Disappearance after Field Treatment and during Processing into Byproducts

2021 ◽  
Author(s):  
Alberto Angioni ◽  
Nicola Arru
Keyword(s):  
Degradation Rate ◽  
Dilution Effect ◽  
Life Time ◽  
Industrial Applications ◽  
Raw Material ◽  
Epicuticular Waxes ◽  
Industrial Processing ◽  
Table Olive ◽  
Major Factors ◽  
Processing Techniques

Insecticide\'s disappearance after field treatments could be ascribed to different factors such as sunlight photodegradation, dilution effect due to fruit growth, co-distillation during fruit respiration and evaporation. Moreover, the epicuticular waxes could speed or slow down the degradation rate, and the cultivation in an open field or greenhouses could affect the residues dramatically. After harvest, the processing techniques to produce byproducts deeply influence insecticide residues. For example, fruit drying, winemaking, the industrial processing of tomatoes to produce purée, triple-concentrated paste, fine pulp, diced, olive processing to obtain table olive and olive oil, and other industrial applications on fruits affect residues and their half-life time. The scope of this chapter is to highlight the major factors responsible for the disappearance of insecticides after treatment. Moreover, the chapter intends to review the influence of the industrial processes on insecticide behaviour when the raw material is transformed into its byproducts.

Sign in / Sign up

Export Citation Format

Share Document