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Article
Publication date: 18 October 2018

Lijun Ding, Shuguang Dai and Pingan Mu

Measurement uncertainty calculation is an important and complicated problem in digitised components inspection. In such inspections, a coordinate measuring machine (CMM) and laser…

Abstract

Purpose

Measurement uncertainty calculation is an important and complicated problem in digitised components inspection. In such inspections, a coordinate measuring machine (CMM) and laser scanner are usually used to get the surface point clouds of the component in different postures. Then, the point clouds are registered to construct fully connected point clouds of the component’s surfaces. However, in most cases, the measurement uncertainty is difficult to estimate after the scanned point cloud has been registered. This paper aims to propose a simplified method for calculating the uncertainty of point cloud measurements based on spatial feature registration.

Design/methodology/approach

In the proposed method, algorithmic models are used to calculate the point cloud measurement uncertainty based on noncontact measurements of the planes, lines and points of the component and spatial feature registration.

Findings

The measurement uncertainty based on spatial feature registration is related to the mutual position of registration features and the number of sensor commutation in the scanning process, but not to the spatial distribution of the measured feature. The results of experiments conducted verify the efficacy of the proposed method.

Originality/value

The proposed method provides an efficient algorithm for calculating the measurement uncertainty of registration point clouds based on part features, and therefore has important theoretical and practical significance in digitised components inspection.

Details

Sensor Review, vol. 39 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 11 March 2014

Suyong Yeon, ChangHyun Jun, Hyunga Choi, Jaehyeon Kang, Youngmok Yun and Nakju Lett Doh

– The authors aim to propose a novel plane extraction algorithm for geometric 3D indoor mapping with range scan data.

Abstract

Purpose

The authors aim to propose a novel plane extraction algorithm for geometric 3D indoor mapping with range scan data.

Design/methodology/approach

The proposed method utilizes a divide-and-conquer step to efficiently handle huge amounts of point clouds not in a whole group, but in forms of separate sub-groups with similar plane parameters. This method adopts robust principal component analysis to enhance estimation accuracy.

Findings

Experimental results verify that the method not only shows enhanced performance in the plane extraction, but also broadens the domain of interest of the plane registration to an information-poor environment (such as simple indoor corridors), while the previous method only adequately works in an information-rich environment (such as a space with many features).

Originality/value

The proposed algorithm has three advantages over the current state-of-the-art method in that it is fast, utilizes more inlier sensor data that does not become contaminated by severe sensor noise and extracts more accurate plane parameters.

Details

Industrial Robot: An International Journal, vol. 41 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 11 July 2019

Mostafa Safdari Ranjbar, Tae-Young Park, Soroush Ghazinoori and Manochehr Manteghi

This paper aims to investigate the pattern of technological capability building in the gas turbine industry as a complex product system (CoPS) in an Iranian gas turbine producer…

Abstract

Purpose

This paper aims to investigate the pattern of technological capability building in the gas turbine industry as a complex product system (CoPS) in an Iranian gas turbine producer named Oil Turbo Compressor Company (OTC) and to recognize multi-level (firm, industry and national) drivers influencing technological catching up in this company.

Design/methodology/approach

This paper used a qualitative approach and case study research strategy. A preliminary theoretical framework is proposed based on research background. Also, the data were collected from various sources, including the interview with 11 experts, studying many documents and participating in some relevant meetings and conventions. To analyze the data, the authors relied on their preliminary theoretical framework and applied the chronological sequence analysis technique.

Findings

Our findings show that, first, in contrast with mass-produced industries where capability building pattern often leads to product innovation, technological capabilities in OTC have evolved from assembling to manufacturing, upgrading and finally redesigning of existing models of gas turbines. Second, two firm-level (proper technology acquisition strategies and building organizational and managerial capabilities), two industry-level (networking, integration and collaboration among key actors and existence of local market and demand) and two national-level (government’s policies, supports and initiatives and institutional arrangement and political conditions) drivers have played indispensable roles in facilitating and accelerating technological catching up by OTC.

Research limitations/implications

Inevitably, the current research faces a few limitations. For instance, the difficulty of generalization is considered an inherent problem because it is a case study of only one Iranian latecomer company, as well as only one CoPS industry. Regarding implications, the findings suggest that technological catching up in CoPS industries in developing countries is not a simple and autonomous process and is influenced by multi-level factors, including national-, industry- and firm-level drivers.

Originality/value

In terms of theory, this paper tends to investigate and explain the catching-up process in OTC as an Iranian gas turbine producer by applying a multi-level theoretical framework that consists of firm-, industry- and national-level drivers. In terms of practice, this paper aims at investigating drivers affecting the catching-up process in a CoPS industry in a developing country that was faced with vast international sanctions, while many other studies in this area examined cases from developing countries such as Korea and China that had the opportunity of enjoying international collaborations and overseas knowledge flows.

Details

Journal of Science and Technology Policy Management, vol. 11 no. 1
Type: Research Article
ISSN: 2053-4620

Keywords

Article
Publication date: 19 June 2017

Bo Sun, Yadan Zeng, Houde Dai, Junhao Xiao and Jianwei Zhang

This paper aims to present the spherical entropy image (SEI), a novel global descriptor for the scan registration of three-dimensional (3D) point clouds. This paper also…

Abstract

Purpose

This paper aims to present the spherical entropy image (SEI), a novel global descriptor for the scan registration of three-dimensional (3D) point clouds. This paper also introduces a global feature-less scan registration strategy based on SEI. It is advantageous for 3D data processing in the scenarios such as mobile robotics and reverse engineering.

Design/methodology/approach

The descriptor works through representing the scan by a spherical function named SEI, whose properties allow to decompose the six-dimensional transformation into 3D rotation and 3D translation. The 3D rotation is estimated by the generalized convolution theorem based on the spherical Fourier transform of SEI. Then, the translation recovery is determined by phase only matched filtering.

Findings

No explicit features and planar segments should be contained in the input data of the method. The experimental results illustrate the parameter independence, high reliability and efficiency of the novel algorithm in registration of feature-less scans.

Originality/value

A novel global descriptor (SEI) for the scan registration of 3D point clouds is presented. It inherits both descriptive power of signature-based methods and robustness of histogram-based methods. A high reliability and efficiency registration method of scans based on SEI is also demonstrated.

Details

Industrial Robot: An International Journal, vol. 44 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 2 February 2024

Bushi Chen, Xunyu Zhong, Han Xie, Pengfei Peng, Huosheng Hu, Xungao Zhong and Qiang Liu

Autonomous mobile robots (AMRs) play a crucial role in industrial and service fields. The paper aims to build a LiDAR-based simultaneous localization and mapping (SLAM) system…

Abstract

Purpose

Autonomous mobile robots (AMRs) play a crucial role in industrial and service fields. The paper aims to build a LiDAR-based simultaneous localization and mapping (SLAM) system used by AMRs to overcome challenges in dynamic and changing environments.

Design/methodology/approach

This research introduces SLAM-RAMU, a lifelong SLAM system that addresses these challenges by providing precise and consistent relocalization and autonomous map updating (RAMU). During the mapping process, local odometry is obtained using iterative error state Kalman filtering, while back-end loop detection and global pose graph optimization are used for accurate trajectory correction. In addition, a fast point cloud segmentation module is incorporated to robustly distinguish between floor, walls and roof in the environment. The segmented point clouds are then used to generate a 2.5D grid map, with particular emphasis on floor detection to filter the prior map and eliminate dynamic artifacts. In the positioning process, an initial pose alignment method is designed, which combines 2D branch-and-bound search with 3D iterative closest point registration. This method ensures high accuracy even in scenes with similar characteristics. Subsequently, scan-to-map registration is performed using the segmented point cloud on the prior map. The system also includes a map updating module that takes into account historical point cloud segmentation results. It selectively incorporates or excludes new point cloud data to ensure consistent reflection of the real environment in the map.

Findings

The performance of the SLAM-RAMU system was evaluated in real-world environments and compared against state-of-the-art (SOTA) methods. The results demonstrate that SLAM-RAMU achieves higher mapping quality and relocalization accuracy and exhibits robustness against dynamic obstacles and environmental changes.

Originality/value

Compared to other SOTA methods in simulation and real environments, SLAM-RAMU showed higher mapping quality, faster initial aligning speed and higher repeated localization accuracy.

Details

Industrial Robot: the international journal of robotics research and application, vol. 51 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 14 June 2011

Jin Sun, Juntong Xi, Xiaobo Chen and Yaoyang Xiong

The purpose of this paper is to describe a computer‐aided design/manufacturing (CAD/CAM) system for fabricating facial prostheses.

1119

Abstract

Purpose

The purpose of this paper is to describe a computer‐aided design/manufacturing (CAD/CAM) system for fabricating facial prostheses.

Design/methodology/approach

The CAD/CAM system can be used for fabricating custom‐made facial prostheses with symmetrical or asymmetrical features. This system integrates non‐contact structured light scanning, reverse engineering and rapid prototyping manufacturing technology. Fringe projection based on the combination of the phase‐shift and grey‐code methods is used for data collection. A robust approach is proposed to calculate the mid‐plane of the human face without any knowledge of the centroid position or the principal axis in data processing.

Findings

Results show that the proposed method increases the fabrication accuracy and reduces the operating time. Patients were satisfied with the rehabilitation results as the custom‐made facial prostheses fitted them well.

Practical implications

This study improves the fabrication accuracy of facial prostheses. Three‐dimensional data of the facial surface of a patient needing a facial prosthesis were obtained with almost no harm to his body; after a series of robust processes, a precise and suitable aesthetic facial prosthesis was fabricated.

Originality/value

This system has bright prospects for clinical application because of its advantages over other methods in terms of speed, accuracy, safety, cost, etc.

Details

Rapid Prototyping Journal, vol. 17 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 13 October 2023

Kai Wang, Jiaying Liu, Shuai Yang, Jing Guo and Yongzhen Ke

This paper aims to automatically obtain the implant parameter from the CBCT images to improve the outcome of implant planning.

Abstract

Purpose

This paper aims to automatically obtain the implant parameter from the CBCT images to improve the outcome of implant planning.

Design/methodology/approach

This paper proposes automatic simulated dental implant positioning on CBCT images, which can significantly improve the efficiency of implant planning. The authors introduce the fusion point calculation method for the missing tooth's long axis and root axis based on the dental arch line used to obtain the optimal fusion position. In addition, the authors proposed a semi-interactive visualization method of implant parameters that be automatically simulated by the authors' method. If the plan does not meet the doctor's requirements, the final implant plan can be fine-tuned to achieve the optimal effect.

Findings

A series of experimental results show that the method proposed in this paper greatly improves the feasibility and accuracy of the implant planning scheme, and the visualization method of planting parameters improves the planning efficiency and the friendliness of system use.

Originality/value

The proposed method can be applied to dental implant planning software to improve the communication efficiency between doctors, patients and technicians.

Details

Engineering Computations, vol. 40 no. 9/10
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 17 August 2012

Janusz Będkowski, Andrzej Masłowski and Geert De Cubber

The purpose of this paper is to demonstrate a real time 3D localization and mapping approach for the USAR (Urban Search and Rescue) robotic application, focusing on the…

Abstract

Purpose

The purpose of this paper is to demonstrate a real time 3D localization and mapping approach for the USAR (Urban Search and Rescue) robotic application, focusing on the performance and the accuracy of the General‐purpose computing on graphics processing units (GPGPU)‐based iterative closest point (ICP) 3D data registration implemented using modern GPGPU with FERMI architecture.

Design/methodology/approach

The authors put all the ICP computation into GPU, and performed the experiments with registration up to 106 data points. The main goal of the research was to provide a method for real‐time data registration performed by a mobile robot equipped with commercially available laser measurement system 3D. The main contribution of the paper is a new GPGPU based ICP implementation with regular grid decomposition. It guarantees high accuracy as equivalent CPU based ICP implementation with better performance.

Findings

The authors have shown an empirical analysis of the tuning of GPUICP parameters for obtaining much better performance (acceptable level of the variance of the computing time) with minimal lost of accuracy. Loop closing method is added and demonstrates satisfactory results of 3D localization and mapping in urban environments. This work can help in building the USAR mobile robotic applications that process 3D cloud of points in real time.

Practical implications

This work can help in developing real time mapping for USAR robotic applications.

Originality/value

The paper proposes a new method for nearest neighbor search that guarantees better performance with minimal loss of accuracy. The variance of computational time is much less than SoA.

Article
Publication date: 1 June 1992

THE Garuda Maintenance Facility (GMF) is an integral part and the backbone of the maintenance of its fleet of planes as they provide domestic, regional and international air…

Abstract

THE Garuda Maintenance Facility (GMF) is an integral part and the backbone of the maintenance of its fleet of planes as they provide domestic, regional and international air transportation services. The GMF provides Garuda Indonesia, the flag carrier, with a competitive advantage amidst the increasingly keen atmosphere of competition in international air transport.

Details

Aircraft Engineering and Aerospace Technology, vol. 64 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 24 September 2019

Kun Wei, Yong Dai and Bingyin Ren

This paper aims to propose an identification method based on monocular vision for cylindrical parts in cluttered scene, which solves the issue that iterative closest point (ICP…

Abstract

Purpose

This paper aims to propose an identification method based on monocular vision for cylindrical parts in cluttered scene, which solves the issue that iterative closest point (ICP) algorithm fails to obtain global optimal solution, as the deviation from scene point cloud to target CAD model is huge in nature.

Design/methodology/approach

The images of the parts are captured at three locations by a camera amounted on a robotic end effector to reconstruct initial scene point cloud. Color signatures of histogram of orientations (C-SHOT) local feature descriptors are extracted from the model and scene point cloud. Random sample consensus (RANSAC) algorithm is used to perform the first initial matching of point sets. Then, the second initial matching is conducted by proposed remote closest point (RCP) algorithm to make the model get close to the scene point cloud. Levenberg Marquardt (LM)-ICP is used to complete fine registration to obtain accurate pose estimation.

Findings

The experimental results in bolt-cluttered scene demonstrate that the accuracy of pose estimation obtained by the proposed method is higher than that obtained by two other methods. The position error is less than 0.92 mm and the orientation error is less than 0.86°. The average recognition rate is 96.67 per cent and the identification time of the single bolt does not exceed 3.5 s.

Practical implications

The presented approach can be applied or integrated into automatic sorting production lines in the factories.

Originality/value

The proposed method improves the efficiency and accuracy of the identification and classification of cylindrical parts using a robotic arm.

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