Mechanical Sciences最新文献_第8页

Design and analysis of a hollow-ring permanent magnet brake for robot joints 机器人关节用空心环永磁制动器的设计与分析

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-08-05 DOI: 10.5194/ms-13-687-2022

Ruoyu Tan, Jieji Zheng, Bin Yu, Baoyu Li, D. Fan, Xin Xie

{"title":"Design and analysis of a hollow-ring permanent magnet brake for robot joints","authors":"Ruoyu Tan, Jieji Zheng, Bin Yu, Baoyu Li, D. Fan, Xin Xie","doi":"10.5194/ms-13-687-2022","DOIUrl":"https://doi.org/10.5194/ms-13-687-2022","url":null,"abstract":"Abstract. An electromagnetic brake is the key basic component to\u0000ensure the safety of robot joints. The conventional electromagnetic brake\u0000mostly uses a set of springs to provide braking force and solenoid power to provide a recovery force, which makes this kind of brake with large thickness\u0000and small braking torque that is not conducive to the application in light and\u0000small joint components. In many design processes, unclear understanding of\u0000the machine-electric-magnetic coupling characteristics leads to relatively\u0000simple theoretical models and inaccurate theoretical results, which do not\u0000provide more help for subsequent designs. In this paper, a hollow-ring type\u0000permanent magnetic power-loss protection brake, integrated inside a joint\u0000assembly, is designed. The brake uses rare earth Nd–Fe–B permanent magnets to\u0000provide braking suction instead of ordinary spring packs, and achieves\u0000motion guidance and braking torque transmission by means of leaf spring.\u0000Combined with the deformation model of the leaf spring and the magnetic\u0000circuit models of the brake under the power-on and power-off conditions,\u0000the overall coupling dynamics model of the brake is established. The\u0000theoretical results are compared through finite-element software, and a prototype is produced for experimental testing. Finally, the accuracy and\u0000validity of the theoretical model are verified, providing a theoretical and\u0000experimental basis for the design of this type of brake.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47585495","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

Electromyogram-based motion compensation control for the upper limb rehabilitation robot in active training 基于肌电图的上肢康复机器人主动训练运动补偿控制

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-08-03 DOI: 10.5194/ms-13-675-2022

Qiaoling Meng, Yiming Yue, Sujiao Li, Hongliu Yu

{"title":"Electromyogram-based motion compensation control for the upper limb rehabilitation robot in active training","authors":"Qiaoling Meng, Yiming Yue, Sujiao Li, Hongliu Yu","doi":"10.5194/ms-13-675-2022","DOIUrl":"https://doi.org/10.5194/ms-13-675-2022","url":null,"abstract":"Abstract. Active participation in training is very important for improving the rehabilitation effect for patients with upper limb dysfunction. However,\u0000traditional upper limb rehabilitation robots cannot drive the patients' arms\u0000by following their varying motion intents during active training. This\u0000control strategy can weaken the patients' active participation. This paper\u0000proposes a novel center-driven upper limb rehabilitation robot and an\u0000electromyogram (EMG)-based motion compensation control method for the upper limb rehabilitation robot in active training in order to improve the patients'\u0000active participation. In addition, the trajectory planning equations for the\u0000proposed robot manipulator are analyzed and built in order to provide the reference trajectory in active training. In the end, two experiments are\u0000carried out to verify the proposed control method. The EMG compensation\u0000experiments show that the maximum error between the theoretical and\u0000experimental motor rotating speeds is no more than 1.3 %. The active training control experiment results show that the proposed robot can implement the reference trajectory in real time. The control method can implement the positive relationship between the rotating speed and the intensity of EMG emerging during upper limb training. It shows that the proposed rehabilitation robot can provide auxiliary force according to the patients' motion intents.\u0000The proposed rehabilitation robot can guide the patients in implementing the reference task in active training.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42974212","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 of an origami-based cylindrical deployable mechanism 基于折纸的圆柱形可展开机构的设计

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-08-03 DOI: 10.5194/ms-13-659-2022

Long Huang, Peng Zeng, Lairong Yin, Juan Huang

引用次数: 7

Research on adaptive speed control method of an autonomous vehicle passing a speed bump on the highway based on a genetic algorithm 基于遗传算法的自动驾驶汽车过减速带自适应速度控制方法研究

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-07-21 DOI: 10.5194/ms-13-647-2022

Longjun Wang, Zhiyong Yang, Xiangdong Chen, R. Zhang, Yu Zhou

{"title":"Research on adaptive speed control method of an autonomous vehicle passing a speed bump on the highway based on a genetic algorithm","authors":"Longjun Wang, Zhiyong Yang, Xiangdong Chen, R. Zhang, Yu Zhou","doi":"10.5194/ms-13-647-2022","DOIUrl":"https://doi.org/10.5194/ms-13-647-2022","url":null,"abstract":"Abstract. When autonomous vehicles pass through uneven roads, especially the consecutive speed control humps (SCHs) on expressways, the\u0000speed of them will have a significant influence on the safety and comfort of\u0000driving. How to automatically select the most appropriate speed has become a\u0000practical research subject. This paper studies the nonlinear vibration\u0000process of the suspension system when the autonomous vehicle passes through\u0000the SCHs on a highway. Firstly, the paper establishes a\u0000four-degree-of-freedom (4-DOF) nonlinear half-vehicle model and a\u0000stimulation function of trapezoidal SCHs and then uses the Runge–Kutta method to numerically solve the differential equations of motion of the suspension system. In the next part, the paper chooses the genetic algorithm to build a\u0000multi-objective optimization problem model, which selects the vertical\u0000displacement of the vehicle body, the suspension's dynamic deflection and the dynamic load of the tire as optimization objectives and combines the method\u0000of the unified objective function to find the optimal passing speed. Finally, the paper designs and carries out the solution process of the\u0000multi-objective optimization problem for the vehicle under three scenarios, conventional passive suspension, semi-active suspension, active suspension,\u0000and compares the optimized state with the pre-optimized state to prove the\u0000effectiveness of the optimization model.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43565141","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

Stiffness analysis of a 3-DOF parallel mechanism for engineering special machining 工程特殊加工三自由度并联机构刚度分析

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-07-20 DOI: 10.5194/ms-13-635-2022

Haiqiang Zhang, J. Tang, Changtao Yan, G. Cui, Minghui Zhang, Yan’an Yao

{"title":"Stiffness analysis of a 3-DOF parallel mechanism for engineering special machining","authors":"Haiqiang Zhang, J. Tang, Changtao Yan, G. Cui, Minghui Zhang, Yan’an Yao","doi":"10.5194/ms-13-635-2022","DOIUrl":"https://doi.org/10.5194/ms-13-635-2022","url":null,"abstract":"Abstract. There are considerably rigorous requirements for accuracy\u0000and stability of the mechanism to accomplish large-scale and complex surface\u0000machining tasks in the aerospace field. In order to improve the stiffness\u0000performance of the parallel mechanism, this paper proposes a novel three\u0000degrees of freedom (DOF) redundantly actuated 2RPU-2SPR (where R, P, U and\u0000S stand for revolute, prismatic, universal and spherical joints,\u0000respectively) parallel mechanism. Firstly, the kinematics position inverse\u0000solution is derived and a dimensionless generalized Jacobian matrix is\u0000established through the driving Jacobian matrix and constraint Jacobian\u0000matrix. Secondly, the stiffness model of the parallel mechanism is deduced and\u0000the accuracy of the stiffness model is verified through finite-element analysis. Using eigenscrew decomposition to illustrate the physical interpretation of the\u0000stiffness matrix, the stiffness matrix is equivalent to six simple screw\u0000springs. Finally, the simulation experiment results demonstrate that\u0000redundantly actuated parallel mechanism has better stiffness performance\u0000compared to the traditional 2RPU-SPR parallel mechanism.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43281656","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

Short communication: Experiment study on micro-textured tool with internal cooling 短通信:内冷微织构刀具的实验研究

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-07-20 DOI: 10.5194/ms-13-619-2022

Gang Yang, Wei Feng

引用次数: 1

Structural analysis of ancient Chinese textile mechanisms 中国古代纺织机械结构分析

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-07-20 DOI: 10.5194/ms-13-625-2022

Shi-wu Li, Kan Shi, M. Wang, Yan-an Yao

引用次数: 0

Dynamic modeling of a metro vehicle considering the motor–gearbox transmission system under traction conditions 考虑电动机-齿轮箱传动系统的地铁车辆牵引动力学建模

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-07-15 DOI: 10.5194/ms-13-603-2022

Tao Zhang, Taimu Jin, Ziwei Zhou, Zaigang Chen, Kaiyun Wang

{"title":"Dynamic modeling of a metro vehicle considering the motor–gearbox transmission system under traction conditions","authors":"Tao Zhang, Taimu Jin, Ziwei Zhou, Zaigang Chen, Kaiyun Wang","doi":"10.5194/ms-13-603-2022","DOIUrl":"https://doi.org/10.5194/ms-13-603-2022","url":null,"abstract":"Abstract. As a vital means of transportation to alleviate urban\u0000traffic congestion, the metro vehicle has been developing rapidly in China during recent\u0000years. For the violent vibration and shock under the frequent\u0000switches between traction and braking conditions, higher requirements are\u0000put forward in the drive system. The dynamic performance of the traction\u0000motor and gearbox, which are the key elements in the drive system of the\u0000metro vehicle, is worthy of attention. Based on the classical vehicle–track coupled dynamics and the gear dynamics theory, a vertical–longitudinal dynamics model for a metro vehicle with frame-hung motors and gearboxes is developed in this paper. This model enables the consideration of some complicated excitations, such as external excitations (the track vertical irregularity) and internal excitations (the mesh stiffness and the dynamic transmission error). The established dynamics model is then validated by comparing the simulated results with the field test results in both time domain and time–frequency domain under traction conditions. Consequently, the established dynamics model is demonstrated to be capable of revealing the dynamic performance of the metro vehicle effectively, especially for the traction and transmission system in the entire vehicle vibration environment of a metro. In turn, the results indicate that the gear transmission has a great and lasting effect on the force state of the traction motors and gearboxes compared to its effect on the axle load transfer.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45306417","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

Automatic adjustment of laparoscopic pose using deep reinforcement learning 使用深度强化学习的腹腔镜姿势自动调整

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-06-28 DOI: 10.5194/ms-13-593-2022

Lingtao Yu, Yongqiang Xia, Pengcheng Wang, Lining Sun

{"title":"Automatic adjustment of laparoscopic pose using deep reinforcement learning","authors":"Lingtao Yu, Yongqiang Xia, Pengcheng Wang, Lining Sun","doi":"10.5194/ms-13-593-2022","DOIUrl":"https://doi.org/10.5194/ms-13-593-2022","url":null,"abstract":"Abstract. Laparoscopic arm and instrument arm control tasks are usually accomplished by an operative doctor. Because of intensive workload and long operative time, this method not only causes the operation not to be flow,\u0000but also increases operation risk. In this paper, we propose a method for\u0000automatic adjustment of laparoscopic pose based on vision and deep\u0000reinforcement learning. Firstly, based on the Deep Q Network framework, the raw laparoscopic image is taken as the only input to estimate the Q values\u0000corresponding to joint actions. Then, the surgical instrument pose\u0000information used to formulate reward functions is obtained through object-tracking and image-processing technology. Finally, a deep neural network\u0000adopted in the Q-value estimation consists of convolutional neural networks\u0000for feature extraction and fully connected layers for policy learning. The\u0000proposed method is validated in simulation. In different test scenarios, the\u0000laparoscopic arm can be well automatically adjusted so that surgical\u0000instruments with different postures are in the proper position of the field\u0000of view. Simulation results demonstrate the effectiveness of the method in learning the highly non-linear mapping between laparoscopic images and the optimal action policy of a laparoscopic arm.\u0000","PeriodicalId":18413,"journal":{"name":"Mechanical Sciences","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2022-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44665907","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

Roundness error evaluation in image domain based on an improved bee colony algorithm 基于改进蜂群算法的图像域圆度误差评估

IF 1.4 4区工程技术

Mechanical Sciences Pub Date : 2022-06-23 DOI: 10.5194/ms-13-577-2022

Benchi Jiang, X. Du, Shilei Bian, Lulu Wu

引用次数: 1