Mechanical Sciences最新文献

{"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}

{"title":"Design and experiment of magnetic navigation control system based on fuzzy PID strategy","authors":"G. Geng, Feng Jiang, Chao Chai, Jianming Wu, Yejun Zhu, Guiguan Zhou, M. Xiao","doi":"10.5194/ms-13-921-2022","DOIUrl":"https://doi.org/10.5194/ms-13-921-2022","url":null,"abstract":"Abstract. In view of the difficulties in the navigation of facility\u0000agricultural equipment in a greenhouse environment, which are greatly affected by environmental factors, being difficult to navigate, and low accuracy, a magnetic navigation controller suitable for greenhouse environments is\u0000designed based on fuzzy PID (proportion integration differentiation) control and combined with the principle of\u0000magnetic navigation control in this paper. The magnetic navigation in a greenhouse environment is realised, and the installation test is carried out on the existing agricultural machinery platform. The results show that when driving in a straight line, the straightness error is controlled at ±2.5 cm m−1, and when driving on a bend, the driving deviation is controlled at ±4.5 cm m−1. Therefore, it can be considered that the magnetic navigation control method based on fuzzy PID control designed in the greenhouse environment can effectively improve the accuracy of navigation and promote the application of facility agricultural equipment to a certain extent.\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":"43733510","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}

{"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}

{"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}

{"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}

{"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}

{"title":"Drilling performance analysis of impregnated micro bit","authors":"Dongdong Song, Z. Ren, Yingxin Yang, Y. Chen, Gao Nie, Leichuan Tan, Hao Peng, Z. Li, Xiaojing Chen, Meng Li, H. Ren, Long Zuo","doi":"10.5194/ms-13-867-2022","DOIUrl":"https://doi.org/10.5194/ms-13-867-2022","url":null,"abstract":"Abstract. The cutting mechanical properties of impregnated diamond bit depend on the performance of its cutting elements. Aiming at the factors affecting the\u0000cutting element performance of impregnated diamond bit, the laboratory rock breaking experiment of impregnated micro bit is carried out. The results\u0000show that the breaking work ratio and unit wear first decrease and then increase with the increase of diamond particle size and concentration when\u0000drilling sandstone; the rock breaking efficiency and wear resistance are the highest when the concentration is 125 %. The breaking work ratio\u0000first decreases and then increases with the increase of diamond particle size when drilling limestone; the rock cutting efficiency is the highest\u0000when the concentration is 100 %. With the increase of diamond particle size, the breaking work ratio increases and the unit wear decreases when\u0000drilling granite; the rock cutting efficiency and wear resistance are the highest when the concentration is 150 %.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41683490","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}

{"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}

{"title":"Nonlinear characteristics of the driving model of the coaxial integrated macro–micro composite actuator","authors":"Caofeng Yu, Yu Wang, Zhihao Xiao, Ganyong Wu, Yongyong Duan, Kun Yang","doi":"10.5194/ms-13-843-2022","DOIUrl":"https://doi.org/10.5194/ms-13-843-2022","url":null,"abstract":"Abstract. Nonlinearity is one of the important factors affecting the\u0000positioning accuracy of the macro–micro composite actuator. To improve the\u0000positioning accuracy of the driving model of the macro–micro composite\u0000actuator, this paper combines the research phenomenon of the nonlinear\u0000characteristics of the voice coil motor to model the nonlinear factors that\u0000affect the macro-moving part of the macro–micro composite actuator. Firstly,\u0000based on analyzing its structure and working principle, the variation law of\u0000the magnetic field intensity at the working air gap of the macro-motion part\u0000is analyzed by the finite element method, and the driving force model of the\u0000macro-motion part is established. Secondly, through the magnetic field\u0000simulation analysis, there is a magnetization phenomenon in the mover part,\u0000and the static friction model is established. Then, the experimental data are\u0000acquired and processed by building the experimental test platform of the\u0000actuator, and the variation model of the electromechanical time constant\u0000with the macro-motion displacement is established. Then, combined with the\u0000Stribeck model and the static friction model, the kinetic model of the\u0000macro-motion part is established. Finally, using the least square method\u0000identify the parameter model, the results are compared with the\u0000experiment. The results show that the magnetic field distribution at the\u0000working air gap of the macro-motion part of the macro–micro composite\u0000actuator is relatively uniform, but it is related to the macro-motion\u0000displacement and the macro-motion coil current. When the macro-motion part\u0000of the macro-micro composite actuator starts, the friction model can\u0000approximately reflect the change of friction force, the kinetic\u0000model of the macro-motion part can reflect the dynamic characteristics of\u0000the macro-motion part, and the matching degree is 92.97 %. The research\u0000results lay a theoretical and technical foundation for the development of a\u0000high-speed and large-stroke positioning controller of the macro-motion micro\u0000composite actuator.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46070142","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}

{"title":"Dynamic modeling and experiment of hind leg swimming of beaver-like underwater robot","authors":"Gang Chen, Zhenyu Wang, Jiajun Tu, Donghai Wang","doi":"10.5194/ms-13-831-2022","DOIUrl":"https://doi.org/10.5194/ms-13-831-2022","url":null,"abstract":"Abstract. When the beaver-like underwater robot is swimming, its hind legs provide the\u0000main propulsion force for the body, which is the source of power for the\u0000robot's movement. Hind leg swimming dynamics is the basis for analyzing the\u0000generation and change of propulsion force during the robot swimming process,\u0000which directly determines how the robot swimming trajectory is planned.\u0000However, there are few researches on the swimming dynamics of the hind leg\u0000of a beaver-like underwater robot. This paper proposes a rigid–liquid fusion\u0000dynamics modeling method, which simplifies the swimming dynamics of hind\u0000legs of beaver-like robot to hydrodynamics of webbed feet and rigid body\u0000dynamics of thighs and calves. The hydrodynamics of the bendable webbed foot is\u0000established based on the integral hydrodynamics method, and the rigid body\u0000dynamic model of the thigh and calf is constructed using the Newton–Euler\u0000method. Through the force transmission, the overall swimming dynamic model\u0000of the hind leg is established, and the propulsion and lift force of the hind leg\u0000to body are obtained. The ANSYS Fluent simulation of the movement of robot's\u0000hind leg and underwater single-leg swimming experiments verify the\u0000correctness and effectiveness of the dynamics model. Comparing the theory,\u0000simulation, and experimental results of the propulsion and lift force of the\u0000robot's hind legs under bionic swimming, increased amplitude swimming, and\u0000reduced amplitude swimming, it further verifies the correctness of the\u0000proposed rigid–liquid fusion dynamic modeling method, and proves the\u0000superiority of the robot's bionic swimming trajectory. This study can\u0000provide new ideas for the leg dynamic modeling of underwater swimming robots\u0000with bendable webbed feet, and lay a theoretical foundation for exploring\u0000the swimming mechanical process of underwater robots.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48890831","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}