Mechanical Sciences最新文献_第6页

A real-time and accurate detection approach for bucket teeth falling off based on improved YOLOX 基于改进YOLOX的斗齿脱落实时准确检测方法

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-11-25 DOI: 10.5194/ms-13-979-2022

Jinnan Lu, Yang Liu

{"title":"A real-time and accurate detection approach for bucket teeth falling off based on improved YOLOX","authors":"Jinnan Lu, Yang Liu","doi":"10.5194/ms-13-979-2022","DOIUrl":"https://doi.org/10.5194/ms-13-979-2022","url":null,"abstract":"Abstract. An electric shovel is a bucket-equipped mining excavator widely used in open-pit mining today. The prolonged direct impact between the\u0000bucket teeth and the ore during the mining process will cause the teeth to\u0000loosen prematurely or even break, resulting in unplanned downtime and\u0000productivity losses. To solve this problem, we propose a real-time and\u0000accurate detection algorithm of bucket teeth falling off based on improved\u0000YOLOX. Firstly, to solve the problem of poor detection effect caused by uneven illumination, the dilated convolution attention mechanism is added to\u0000enhance the feature expression ability of the target in complex backgrounds\u0000so as to improve the detection accuracy of the target. Secondly, considering\u0000the high computing cost and large delay of the embedded device, the deep\u0000separable convolution is used to replace the traditional convolution in the\u0000feature pyramid network, and the model compression strategy is used to prune\u0000the redundant channels in the network, reduce the model volume, and improve\u0000the detection speed. The performance test is carried out on the\u0000self-constructed dataset of WK-10 electric shovel. The experimental results show that, compared with the YOLOX model, the mean average precision of the\u0000algorithm in this paper reaches 95.26 %, only 0.33 % lower, while the\u0000detection speed is 50.8 fps, 11.9 fps higher, and the model volume is 28.42 MB,\u0000which is reduced to 29.46 % of the original. Compared with many other\u0000existing methods, the target detection algorithm proposed in this paper has\u0000the advantages of higher precision, smaller model volume, and faster speed.\u0000It can meet the requirements of real-time and accurate detection of the\u0000bucket teeth falling off.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48014232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research on structural parameters and kinematic properties of a drill-in granary grain condition detector 粮仓粮情检测仪钻头结构参数及运动特性研究

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-11-17 DOI: 10.5194/ms-13-961-2022

Q. Yin, Junpeng Yu, Shaoyun Song, Yonglin Zhang, Gang Zhao, Zhiqiang Hao, Ao Hu

{"title":"Research on structural parameters and kinematic properties of a drill-in granary grain condition detector","authors":"Q. Yin, Junpeng Yu, Shaoyun Song, Yonglin Zhang, Gang Zhao, Zhiqiang Hao, Ao Hu","doi":"10.5194/ms-13-961-2022","DOIUrl":"https://doi.org/10.5194/ms-13-961-2022","url":null,"abstract":"Abstract. In order to realize the real-time monitoring of the grain condition, grain condition information should be collected during storage operations. A drill-in granary grain condition detector which can drill into a grain pile in a granary is proposed. The kinematic models of four Archimedes screw mechanisms were established, and the motion characteristics of grain particles in spiral grooves were described. Several groups of single variable simulation experiments are designed to discuss the important factors affecting the motion performance of the detector. Based on a discrete element method with multi-body dynamics (DEM-MBD) simulation calculation, the force and velocity change images of grain particles were obtained to verify the feasibility of the scheme. The\u0000steering function of the detector is verified by simulation, and the\u0000relationship between the steering radius and the screw rotation speed\u0000difference is analyzed. The results show that the drill-in granary grain\u0000condition detector can move forward and turn when it is immersed in the\u0000grain pile. It has the characteristics of excellent flexibility and a high\u0000degree of freedom. It compensates for the current situation in which robots\u0000cannot go deep inside the grain pile and complete the steering.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41423619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of a force-field-based control strategy for an upper-limb rehabilitation robot 基于力场的上肢康复机器人控制策略研究

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-11-17 DOI: 10.5194/ms-13-949-2022

Jiasheng Pan, Leigang Zhang, Qing Sun

{"title":"Development of a force-field-based control strategy for an upper-limb rehabilitation robot","authors":"Jiasheng Pan, Leigang Zhang, Qing Sun","doi":"10.5194/ms-13-949-2022","DOIUrl":"https://doi.org/10.5194/ms-13-949-2022","url":null,"abstract":"Abstract. Robot-assisted rehabilitation has proven to be\u0000effective for improving the motor performance of patients with neuromuscular\u0000injuries. The effectiveness of robot-assisted training directly depends on\u0000the control strategy applied in the therapy training. This paper presents an\u0000end-effector upper-limb rehabilitation robot for the functional recovery\u0000training of disabled patients. A force-field-based rehabilitation\u0000control strategy is then developed to induce active patient participation\u0000during training tasks. The proposed control strategy divides the\u00003D space around the rehabilitation training path into\u0000a human-dominated area and a robot-dominated area. It encodes the space around the\u0000training path and endows the corresponding normal and tangential force; the\u0000tangential component assists with movement along the target path, and the normal\u0000component pushes the patient's hand towards the target path using a\u0000real-time adjustable controller. Compared with a common force-field\u0000controller, the human–robot interaction in this strategy is easy and can be quickly\u0000adjusted by changing the force field's range or the variation characteristics\u0000of two forces, and the intervention in two directions can change\u0000continuously and smoothly despite the patient's hand crossing the two areas. Visual\u0000guidance based on the Unity-3D environment is introduced to provide visual\u0000training instructions. Finally, the feasibility of the proposed control\u0000scheme is validated via training experiments using five healthy subjects.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49264974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Design and experiment of magnetic navigation control system based on fuzzy PID strategy 基于模糊PID策略的磁导航控制系统设计与实验

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-11-08 DOI: 10.5194/ms-13-921-2022

G. Geng, Feng Jiang, Chao Chai, Jianming Wu, Yejun Zhu, Guiguan Zhou, M. Xiao

引用次数: 0

The evolution and restoration of European vertically arranged mechanical turret clocks before the 17th century 17世纪以前欧洲垂直排列的机械转塔钟的演变和修复

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-11-08 DOI: 10.5194/ms-13-933-2022

Tsung-Yi Lin, Wen-Feng Lin

{"title":"The evolution and restoration of European vertically arranged mechanical turret clocks before the 17th century","authors":"Tsung-Yi Lin, Wen-Feng Lin","doi":"10.5194/ms-13-933-2022","DOIUrl":"https://doi.org/10.5194/ms-13-933-2022","url":null,"abstract":"Abstract. From the 14th to 17th century in Europe, a variety of types of mechanical turret clocks were manufactured, many of which have been replaced or\u0000abandoned. At present, vertically arranged mechanical turret clocks can be rarely found. This study mainly analyzed the mechanism and technology of\u0000nine existing vertically arranged mechanical turret clocks manufactured in Europe from the 15th to the 17th century, in order to determine the\u0000design rules based on mechanical evolution and variation. The systematical restoration of vertically arranged mechanical turret clocks in history\u0000has resulted in 16 representative mechanism configurations of movements of mechanical turret clocks. The content and results of this study can\u0000provide its readers a clearer understanding about the mechanism design and technology of the vertically arranged mechanical turret clocks of each\u0000period throughout history in order to establish a comprehensive knowledge system. Furthermore, understanding the design concept of the vertically arranged\u0000mechanical turret clock contributes to the establishment of every possible restoration design construction throughout history. These innovative\u0000results not only provide new historical materials that could be applied in the research of science and technology history, but also contribute to\u0000the development of creativity and science education teaching materials.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48915964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Surface modification and tooth contact analysis of variable hyperbolic circular-arc-tooth-trace cylindrical gears 变双曲圆弧齿线圆柱齿轮表面修形及齿面接触分析

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-11-04 DOI: 10.5194/ms-13-909-2022

Yongping Liu, Dengqiu Ma

{"title":"Surface modification and tooth contact analysis of variable hyperbolic circular-arc-tooth-trace cylindrical gears","authors":"Yongping Liu, Dengqiu Ma","doi":"10.5194/ms-13-909-2022","DOIUrl":"https://doi.org/10.5194/ms-13-909-2022","url":null,"abstract":"Abstract. To improve the bearing capacity and provide the mathematical model basis for vibration and noise reduction of the variable hyperbolic circular-arc-tooth-trace (VH-CATT) cylindrical gear, the tooth surface modification design method based on the parabolic forming blade and cutter inclination was proposed. The geometric design of inclined cutter was completed. The modified tooth surface equation was deduced, and the influence of modification parameters on tooth surface curvature characteristics was analysed further. The tooth contact analysis (TCA) was established, and the influence of modification parameters on the elliptical contact area was analysed. Research shows that the parabolic coefficient a and the parabolic vertex position u0 have effects on the main curvature of concave–convex tooth surface, both the tooth profile and the tooth line direction, but the cutter inclination angle only has influence on the curvature of the tooth line direction, and the influence is larger. The cutter inclination angle γ, parabola coefficient a, and parabolic vertex position u0 have certain influences on the elliptical contact area. The cutter inclination angle γ is the most important modification parameter to improve the bearing capacity, but the excessive cutter inclination angle will cause bridge contact, the value range cutter inclination γ can be determined based on the tooth line radius. The research results provide a technical basis for improving the bearing capacity of the VH-CATT cylindrical gear and optimising the design.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48705385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adaptive sliding-mode control for improved vibration mitigation in civil engineering structures 改进土木工程结构减振的自适应滑模控制

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-10-28 DOI: 10.5194/ms-13-899-2022

Khaled Zizouni, A. Saidi, Leyla Fali, I. K. Bousserhane, M. Djermane

{"title":"Adaptive sliding-mode control for improved vibration mitigation in civil engineering structures","authors":"Khaled Zizouni, A. Saidi, Leyla Fali, I. K. Bousserhane, M. Djermane","doi":"10.5194/ms-13-899-2022","DOIUrl":"https://doi.org/10.5194/ms-13-899-2022","url":null,"abstract":"Abstract. Seismic vibration control using a magneto-rheological damper is a technique that interests several researchers around the world. This technique offers suitable structural building protection, ensuring human safety against earthquake excitation damages. The robustness of these devices depended in many cases on the designed law of control. Over the years, research focused on the development and modelling of various controllers to enhance the structural vibration elimination of buildings. The emphasis of this paper is on the evaluation of semi-active control robustness to reduce the displacements of a three-storey tested structure. The semi-active control device is a magneto-rheological fluid damper installed on the ground floor of the earthquake's excited structure and is controlled by an adaptive non-linear controller coupled to a clipped optimal algorithm to drive the current. The proposed controller is a sliding-mode controller reinforced by an adaptive technique to perform the control gain choice and overcome the chattering problem. The present law of adaptation is a switching conditional law between two laws offering the required gain depending on the system state. The numerical simulation results prove the effectiveness of the proposed semi-active control strategy in attenuating the displacements of the tested structure.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46587666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evolution and mechanism configuration synthesis of chamber clocks movement prior to 1700 1700年以前座钟机芯的演变和机构构型综合

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-10-21 DOI: 10.5194/ms-13-877-2022

Tsung-Yi Lin, Wen-Feng Lin

{"title":"Evolution and mechanism configuration synthesis of chamber clocks movement prior to 1700","authors":"Tsung-Yi Lin, Wen-Feng Lin","doi":"10.5194/ms-13-877-2022","DOIUrl":"https://doi.org/10.5194/ms-13-877-2022","url":null,"abstract":"Abstract. Chamber clocks are weight-driven wall clocks and the first type of domestic clocks to be widely used in the home. During the 16th and 17th\u0000centuries, although horologists in Europe made various types of chamber clocks in large numbers, many of the clocks have since been either replaced or discarded. In this study, we used the method of mechanical evolution and variation, analyzed and compared clock movements based on historical data and existing clocks, and synthesized all possible movement configurations of early-day chamber clocks. A total of 4 going-train configurations and 10 striking-train configurations were identified, making a total of 40 feasible movement configurations. In addition, 14 existing representative chamber clocks were selected as examples to illustrate the above configurations and their variations, which enabled the creation of a comprehensive atlas of the movement designs. The results of the study can not only help to systematically carry out the reconstruction design of various chamber clocks, but also provide new information for scholars of history of science to further historical research and develop new materials for creativity as well as science and technology education.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48067372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Drilling performance analysis of impregnated micro bit 浸渍微钻头钻井性能分析

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-10-19 DOI: 10.5194/ms-13-867-2022

Dongdong Song, Z. Ren, Yingxin Yang, Y. Chen, Gao Nie, Leichuan Tan, Hao Peng, Z. Li, Xiaojing Chen, Meng Li, H. Ren, Long Zuo

引用次数: 7

Analysis of the coaxiality–geometric hysteresis model of a rotate vector reducer based on Ansys Adams 基于Ansys Adams的旋转矢量减速器同轴度-几何磁滞模型分析

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-10-13 DOI: 10.5194/ms-13-855-2022

Yongming Liu, Lei Fu, Zhuanzhe Zhao, Qiang Ma, Yujian Rui, Zhen Zhang

{"title":"Analysis of the coaxiality–geometric hysteresis model of a rotate vector reducer based on Ansys Adams","authors":"Yongming Liu, Lei Fu, Zhuanzhe Zhao, Qiang Ma, Yujian Rui, Zhen Zhang","doi":"10.5194/ms-13-855-2022","DOIUrl":"https://doi.org/10.5194/ms-13-855-2022","url":null,"abstract":"Abstract. When a traditional performance test device, the rotate\u0000vector (RV) reducer, is loading and unloading the reducer tested or running\u0000in different torque ranges, the coaxiality error generated by the\u0000transmission system has an important impact on the detection accuracy of a\u0000key performance parameter of the RV reducer, the hysteresis. In order to design a\u0000high-precision performance test device, a RV reducer coaxiality–geometric hysteresis model is proposed. First of all, the static simulation analysis\u0000of the transmission system of the traditional performance test device in\u0000different torque ranges is carried out using Ansys software, and the\u0000corresponding coaxiality error is obtained. Secondly, the RV reducer\u0000coaxiality–geometric hysteresis model is established by means of geometric\u0000analysis, and combined with Adams dynamics simulation software, the dynamic\u0000simulation analysis is carried out under the condition that the coaxiality\u0000of the model transmission system is in different error ranges and has no load.\u0000When the coaxiality is within the allowable error range, the hysteresis\u0000value is 0.5467 arcmin, and the result shows that the accuracy of the model is verified.\u0000At the same time, when the coaxiality exceeds the allowable range of error,\u0000it will have a great impact on the hysteresis. This result has certain\u0000theoretical significance and practical value for the analysis of the\u0000influence of the coaxiality error of the high-precision RV reducer\u0000performance detection device and the design of the adjustment mechanism.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49393678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2