A Laser Triangulation-Based 3D Measurement System for Inner Surface of Deep Holes

2018 ◽  
Author(s):  
Zhu Ye ◽  
Wang Lianpo ◽  
Yonggang Gu ◽  
Zhai Chao ◽  
Baoyang Jiang ◽  
...  
Keyword(s):  
Measurement System ◽  
Absolute Error ◽  
Surface Measurement ◽  
Laser Triangulation ◽  
Inspection System ◽  
Maximum Absolute Error ◽  
Measurement Systems ◽  
Laser Plane ◽  
Inner Surface ◽  
3D Measurement System

Basing on the laser-triangulation principle, a deep hole inner surface inspection system is developed in this research. Compared with existing inner surface measurement systems, this research takes assembly errors and refraction distortion into consideration and proposes a flexible laser plane calibration technique based on binocular vision that is easy to operate. The measurement system calibrated by proposed method performs well in the field test in which the maximum absolute error of the measured ring gauge diameter is 3μm. Experiment indicates that this system is accurate and suitable for inner surface measurement. Point cloud registration may be applied in the future to extend the system’s applicability.

Three-Dimensional Inner Surface Inspection System Based on Circle-Structured Light

2018 ◽  
Vol 140 (12) ◽  
Author(s):  
Zhu Ye ◽  
Wang Lianpo ◽  
Gu Yonggang ◽  
Bi Songlin ◽  
Zhai Chao ◽  
...  
Keyword(s):  
Structured Light ◽  
Three Dimensional ◽  
Ccd Camera ◽  
Absolute Error ◽  
Surface Measurement ◽  
Laser Triangulation ◽  
Inspection System ◽  
Surface Inspection ◽  
Laser Plane ◽  
Inner Surface

A three-dimensional (3D) inner surface inspection system is developed in this research based on circle-structured light, which is an improved laser triangulation method. A conical reflector is used to reflect the laser and generate radial laser plane that is called circle-structured light, and a CCD camera is used to capture the light stripe on the inner surface. Then, the 3D coordinates of points on the light stripe are calculated through laser triangulation algorithm. Compared with existing inner surface measurement systems, this research takes assembly errors and refraction distortion into consideration and proposes a laser plane mathematical model with four degrees-of-freedom along with corresponding flexible laser plane calibration technique based on binocular vision that is easy to operate. The proposed inspection system calibrated by proposed algorithm performs well in diameter measurement experiment, in which the absolute error is superior to 3 μm, and defect detecting experiment, in which the defect resolution is superior to 0.02 mm. Moreover, the system also performs well in straightness and roundness evaluation. Experiments indicate that this system is applicable in inner surface measurement and inspection, and the calibration method is accurate and easy to operate.

scholarly journals Drift Analysis of GATE Ship Surface Measurement Systems

1979 ◽  
Vol 60 (9) ◽  
pp. 1077-1083 ◽  
Author(s):  
James S. Goerss
Keyword(s):  
Wind Speed ◽  
Measurement System ◽  
Wind Direction ◽  
Low Frequency ◽  
Sea Surface ◽  
Surface Measurement ◽  
Frequency Noise ◽  
Measurement Systems ◽  
Analysis Scheme ◽  
Drift Analysis

An analysis scheme is developed to estimate drift or low frequency noise in ship measurement systems during GATE. The term “measurement system”. is used to encompass the collection of hand recorded as well as automatically recorded observations. The scheme is applied to ship systems measuring pressure, wet-bulb temperature, sea-surface temperature, dry-bulb temperature, wind speed, and wind direction. The drift analysis scheme is found to be quite successful in estimating the drift for the pressure and temperature measurement systems, but little success is found in the analysis of the wind data. In many cases the analysis scheme provides information about the error content of systems that would otherwise be unavailable and shows that drift corrections based solely on ship intercomparison results can, in some cases, lead to significant errors.

The Corruption of a Measurement System Due to Unintentional Bias: A Preliminary Macro-Ergonomic Study

1998 ◽  
Vol 42 (13) ◽  
pp. 969-973
Author(s):  
Matthew R. James ◽  
Mario G. Beruvides
Keyword(s):  
Mechanical System ◽  
Human Behavior ◽  
Measurement System ◽  
Visual Inspection ◽  
Measurement Techniques ◽  
Inspection System ◽  
Measurement Systems ◽  
Research Questions ◽  
Primary Hypothesis ◽  
Measurement Setting

For the better part of the century, researchers have been analyzing the effect of an external prompt on human behavior. The phenomenon described by previous research has been dubbed the Pygmalion effect. This study looks at the effect an external prompt has on subsequent human behavior in a different setting than traditional Pygmalion studies. It examines the reaction of humans to external prompts in a measurement setting. The primary hypothesis of the research states that in a measurement system, indications about the expected outcome of inspections can lead people to inadvertently change their measurement techniques such that their results are significantly skewed toward the bias value compared to an unprompted group. The study was performed on 24 college students, measuring corruption in two different types of measurement systems, a rigid mechanical system and a visual inspection system. In two of the four measurement tasks in the rigid mechanical system, the evidence supported the hypothesis that a bias can be introduced. In the visual inspection system, each of the two measurement tasks supported the existence of an unintentional measurement bias. This study presents a challenge to the objectivity of measurement systems, which is a generally accepted, and poses several research questions from which future studies can be spawned and is a concern to researchers and practitioners interested in this aspect of macro-ergonomics.

scholarly journals Development of Thermal Performance Metrics for Direct Gas-Fired Circulating Heaters

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 588
Author(s):  
Benjamin C. Smith ◽  
Brett C. Ramirez ◽  
Steven J. Hoff
Keyword(s):  
Mass Flow ◽  
Measurement System ◽  
Thermal Efficiency ◽  
Performance Metrics ◽  
Standardized Test ◽  
Flow System ◽  
Standard Test ◽  
Testing System ◽  
Measurement Systems ◽  
Selection Of

Many climate-controlled agricultural buildings use direct gas-fired circulating heaters (DGFCH) for supplement heat. There is no standardized test to calculate thermal efficiency for these heaters. This study aimed to develop a measurement system and analytical analysis for thermal efficiency, quantify the measurement uncertainty, and assess economics of DGFCH efficiency. The measurement system developed was similar to the ASHRAE 103 standard test stand with adaptations to connect the apparatus to the DGFCH. Two different propane measurement systems were used: input ratings < 30 kW used a mass flow system and input ratings > 30 kW used a volumetric gas meter. Three DGFCHs (21.9, 29.3, 73.3 kW) were tested to evaluate the system. Thermal efficiencies ranged from 92.4% to 100.9%. The resulting uncertainty (coverage factor of 2; ~95% Confidence Interval) ranged from 13.1% to 30.7% for input ratings of 56.3 to 11.4 kW. Key sources of uncertainty were propane and mass flow of air measurement. The economic impact of 1% difference in thermal efficiency ranged from USD $61.3 to $72.0 per heating season. Refinement of the testing system and procedures are needed to reduce the uncertainty. The application of this system will aid building designers in selection of DGFCHs for various applications.

Error Compensation Techniques for Fixed-Width Array Multiplier Design — A Technical Survey

2016 ◽  
Vol 26 (03) ◽  
pp. 1730003 ◽  
Author(s):  
S. Balamurugan ◽  
P. S. Mallick
Keyword(s):  
Error Compensation ◽  
Absolute Error ◽  
Mean Square ◽  
Maximum Absolute Error ◽  
Comprehensive Review ◽  
Related Research ◽  
Error Formula ◽  
Error Metrics ◽  
Array Multiplier ◽  
Future Work

This paper provides a comprehensive review of various error compensation techniques for fixed-width multiplier design along with its applications. In this paper, we have studied different error compensation circuits and their complexities in the fixed-width multipliers. Further, we present the experimental results of error metrics, including normalized maximum absolute error [Formula: see text], normalized mean error [Formula: see text] and normalized mean-square error [Formula: see text] to evaluate the accuracy of fixed-width multipliers. This survey is intended to serve as a suitable guideline and reference for future work in fixed-width multiplier design and its related research.

scholarly journals Simulation Analysis of Magnetic Gradient Full-Tensor Measurement System

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Lei Xu ◽  
Ning Zhang ◽  
Liqing Fang ◽  
Huadong Chen ◽  
Pengfei Lin ◽  
...  
Keyword(s):  
Magnetic Dipole ◽  
Measurement System ◽  
Measurement Accuracy ◽  
Simulation Analysis ◽  
Magnetic Gradient ◽  
Measurement Systems ◽  
Magnetometer Array ◽  
Array Structure ◽  
Simulation Results ◽  
Planar Measurement

The magnetic gradient full-tensor measurement system is diverse, and the magnetometer array structure is complex. Aimed at the problem, seven magnetic gradient full-tensor measurement system models are studied in detail. The full-tensor measurement theories of the tensor measurement arrays are analyzed. Under the same baseline distance, the magnetic dipole model is used to simulate the measurement system. Based on different measurement systems, the paper quantitatively compares and analyzes the error of the structure. A more optimized magnetic gradient full-tensor measurement system is suggested. The simulation results show that the measurement accuracy of the planar measurement system is slightly higher than that of the stereo measurement system. Among them, the cross-shaped and square measurement systems have relatively smaller structural errors and higher measurement accuracy.

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