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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 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-11-17 DOI: 10.5194/ms-13-949-2022
Jiasheng Pan, Leigang Zhang, Qing Sun
Abstract. Robot-assisted rehabilitation has proven to beeffective for improving the motor performance of patients with neuromuscularinjuries. The effectiveness of robot-assisted training directly depends onthe control strategy applied in the therapy training. This paper presents anend-effector upper-limb rehabilitation robot for the functional recoverytraining of disabled patients. A force-field-based rehabilitationcontrol strategy is then developed to induce active patient participationduring training tasks. The proposed control strategy divides the3D space around the rehabilitation training path intoa human-dominated area and a robot-dominated area. It encodes the space around thetraining path and endows the corresponding normal and tangential force; thetangential component assists with movement along the target path, and the normalcomponent pushes the patient's hand towards the target path using areal-time adjustable controller. Compared with a common force-fieldcontroller, the human–robot interaction in this strategy is easy and can be quicklyadjusted by changing the force field's range or the variation characteristicsof two forces, and the intervention in two directions can changecontinuously and smoothly despite the patient's hand crossing the two areas. Visualguidance based on the Unity-3D environment is introduced to provide visualtraining instructions. Finally, the feasibility of the proposed controlscheme is validated via training experiments using five healthy subjects.
摘要机器人辅助康复已被证明对改善神经肌肉损伤患者的运动性能有很大作用。机器人辅助训练的有效性直接取决于治疗训练中应用的控制策略。本文介绍了一种用于残疾患者功能恢复训练的高效上肢康复机器人。然后开发了一种基于力场的康复控制策略,以诱导患者积极参与训练任务。所提出的控制策略将康复训练路径周围的三维空间划分为人类主导区域和机器人主导区域。它对训练路径周围的空间进行编码,并赋予相应的法向力和切向力;所述角度分量有助于沿着所述目标路径的移动,并且所述正常分量使用面积时间可调控制器将患者的手推向目标路径。与普通的力场控制器相比,该策略中的人机交互很容易,可以通过改变力场的范围或两种力的变化特征来快速调整,并且无论患者的手穿过两个区域,两个方向的干预都可以连续而平稳地变化。引入了基于Unity-3D环境的可视化指导,以提供可视化培训指导。最后,通过五名健康受试者的训练实验验证了所提出的控制方案的可行性。
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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 Q4 ENGINEERING, MECHANICAL 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
Abstract. In view of the difficulties in the navigation of facilityagricultural 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 isdesigned based on fuzzy PID (proportion integration differentiation) control and combined with the principle ofmagnetic 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.
摘要针对温室环境下设施农业设备导航困难、受环境因素影响大、导航困难、精度低等问题,结合磁导航控制原理,设计了一种基于模糊PID(比例积分微分)控制的适用于温室环境的磁导航控制器。实现了温室环境下的磁导航,并在现有农机平台上进行了安装试验。结果表明:直线行驶时,直线度误差控制在±2.5 cm m−1,弯道行驶时,驱动偏差控制在±4.5 cm m−1。因此,可以认为在温室环境中设计的基于模糊PID控制的磁导航控制方法,可以有效地提高导航精度,在一定程度上促进设施农业装备的应用。
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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 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-11-08 DOI: 10.5194/ms-13-933-2022
Tsung-Yi Lin, Wen-Feng Lin
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 orabandoned. At present, vertically arranged mechanical turret clocks can be rarely found. This study mainly analyzed the mechanism and technology ofnine existing vertically arranged mechanical turret clocks manufactured in Europe from the 15th to the 17th century, in order to determine thedesign rules based on mechanical evolution and variation. The systematical restoration of vertically arranged mechanical turret clocks in historyhas resulted in 16 representative mechanism configurations of movements of mechanical turret clocks. The content and results of this study canprovide its readers a clearer understanding about the mechanism design and technology of the vertically arranged mechanical turret clocks of eachperiod throughout history in order to establish a comprehensive knowledge system. Furthermore, understanding the design concept of the vertically arrangedmechanical turret clock contributes to the establishment of every possible restoration design construction throughout history. These innovativeresults not only provide new historical materials that could be applied in the research of science and technology history, but also contribute tothe development of creativity and science education teaching materials.
摘要从14世纪到17世纪,欧洲制造了各种类型的机械转塔钟,其中许多已被取代或废弃。目前,垂直排列的机械转塔钟很少见到。本研究主要分析了15世纪至17世纪欧洲生产的九种现有的垂直排列机械转塔钟的机构和工艺,以确定基于机械演化和变化的设计规律。历史上对垂直排列的机械转塔钟进行了系统的修复,形成了16种具有代表性的机械转塔钟机芯机构构型。本研究的内容和结果可以使读者更清楚地了解历史上各个时期垂直排列机械转塔钟的机构设计和技术,从而建立一个全面的知识体系。此外,理解垂直排列的机械塔钟的设计概念有助于建立历史上每一个可能的修复设计施工。这些创新成果不仅为科学技术史研究提供了新的史料,也为创新和科学教育教材的发展做出了贡献。
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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 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-11-04 DOI: 10.5194/ms-13-909-2022
Yongping Liu, Dengqiu Ma
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.
摘要为了提高变双曲圆弧齿迹(VH-CATT)圆柱齿轮的承载能力,为其减振降噪提供数学模型依据,提出了基于抛物面成形刀片和刀具倾斜度的齿面修形设计方法。完成了斜刀的几何设计。推导了修正后的齿面方程,并进一步分析了修正参数对齿面曲率特性的影响。建立了齿面接触分析法(TCA),分析了修正参数对椭圆接触面积的影响。研究表明,抛物线系数a和抛物线顶点位置u0对凹凸齿面的主曲率、齿形和齿线方向都有影响,但刀具倾角只对齿线方向的曲率有影响,而且影响更大。刀具倾角γ、抛物线系数a和抛物线顶点位置u0对椭圆接触面积有一定的影响。刀具倾斜角γ是提高承载力的最重要的修正参数,但过大的刀具倾斜角会引起桥接触,刀具倾斜角的取值范围可以根据齿线半径确定。研究结果为提高VH-CATT圆柱齿轮的承载能力和优化设计提供了技术依据。
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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 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-10-28 DOI: 10.5194/ms-13-899-2022
Khaled Zizouni, A. Saidi, Leyla Fali, I. K. Bousserhane, M. Djermane
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.
摘要使用磁流变阻尼器的地震振动控制是一项引起世界各地研究人员兴趣的技术。这项技术提供了合适的结构建筑保护,确保了人类安全免受地震激励的破坏。这些设备的鲁棒性在许多情况下取决于设计的控制律。多年来,研究重点是开发和建模各种控制器,以增强建筑物的结构振动消除。本文的重点是评估半主动控制的鲁棒性,以减少三层测试结构的位移。半主动控制装置是安装在地震激励结构底层的磁流变流体阻尼器,由自适应非线性控制器控制,该控制器与削波优化算法耦合以驱动电流。所提出的控制器是一种通过自适应技术增强的滑模控制器,以执行控制增益选择并克服抖振问题。目前的适应定律是两个定律之间的切换条件定律,根据系统状态提供所需的增益。数值模拟结果证明了所提出的半主动控制策略在衰减受试结构位移方面的有效性。
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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 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-10-21 DOI: 10.5194/ms-13-877-2022
Tsung-Yi Lin, Wen-Feng Lin
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 17thcenturies, 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.
摘要室内钟是重量驱动的挂钟,也是第一种在家中广泛使用的家用钟。在16世纪和17世纪,尽管欧洲的钟表学家大量制造了各种类型的室内钟,但许多钟后来要么被替换,要么被丢弃。在这项研究中,我们使用了机械进化和变异的方法,基于历史数据和现有时钟对时钟的运动进行了分析和比较,并综合了早期室内钟所有可能的运动配置。共确定了4种行进列车配置和10种打击列车配置,共计40种可行的运动配置。此外,选择了14个现有的具有代表性的室内钟作为例子来说明上述配置及其变体,这使得能够创建一个全面的机芯设计图谱。研究结果不仅有助于系统地进行各种室内钟的重建设计,而且为科学史学者进一步进行历史研究、开发创新和科技教育的新材料提供了新的信息。
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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 Q4 ENGINEERING, MECHANICAL 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
Abstract. The cutting mechanical properties of impregnated diamond bit depend on the performance of its cutting elements. Aiming at the factors affecting thecutting element performance of impregnated diamond bit, the laboratory rock breaking experiment of impregnated micro bit is carried out. The resultsshow that the breaking work ratio and unit wear first decrease and then increase with the increase of diamond particle size and concentration whendrilling sandstone; the rock breaking efficiency and wear resistance are the highest when the concentration is 125 %. The breaking work ratiofirst decreases and then increases with the increase of diamond particle size when drilling limestone; the rock cutting efficiency is the highestwhen the concentration is 100 %. With the increase of diamond particle size, the breaking work ratio increases and the unit wear decreases whendrilling granite; the rock cutting efficiency and wear resistance are the highest when the concentration is 150 %.
摘要浸渍金刚石钻头的切削力学性能取决于其切削元件的性能。针对影响浸渍金刚石钻头切削元件性能的因素,进行了浸渍微钻头的室内破岩试验。结果表明:钻取砂岩时,随着金刚石粒度和浓度的增加,破碎功比和单位磨损量先减小后增大;当浓度为125%时,破岩效率和耐磨性最高。钻取石灰岩时,随着金刚石粒度的增大,破碎功比先减小后增大;当浓度为100%时,岩石切割效率最高。钻取花岗岩时,随着金刚石粒度的增大,破碎功比增大,单位磨损量减小;当浓度为150%时,岩石切削效率和耐磨性最高。
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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 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-10-13 DOI: 10.5194/ms-13-855-2022
Yongming Liu, Lei Fu, Zhuanzhe Zhao, Qiang Ma, Yujian Rui, Zhen Zhang
Abstract. When a traditional performance test device, the rotatevector (RV) reducer, is loading and unloading the reducer tested or runningin different torque ranges, the coaxiality error generated by thetransmission system has an important impact on the detection accuracy of akey performance parameter of the RV reducer, the hysteresis. In order to design ahigh-precision performance test device, a RV reducer coaxiality–geometric hysteresis model is proposed. First of all, the static simulation analysisof the transmission system of the traditional performance test device indifferent torque ranges is carried out using Ansys software, and thecorresponding coaxiality error is obtained. Secondly, the RV reducercoaxiality–geometric hysteresis model is established by means of geometricanalysis, and combined with Adams dynamics simulation software, the dynamicsimulation analysis is carried out under the condition that the coaxialityof the model transmission system is in different error ranges and has no load.When the coaxiality is within the allowable error range, the hysteresisvalue is 0.5467 arcmin, and the result shows that the accuracy of the model is verified.At the same time, when the coaxiality exceeds the allowable range of error,it will have a great impact on the hysteresis. This result has certaintheoretical significance and practical value for the analysis of theinfluence of the coaxiality error of the high-precision RV reducerperformance detection device and the design of the adjustment mechanism.
摘要当传统的性能测试装置RV减速器在不同扭矩范围内加载和卸载测试的减速器或运行时,传动系统产生的同轴度误差对RV减速器性能参数磁滞的检测精度有重要影响。为了设计高精度性能测试装置,提出了RV减速器同轴度-几何磁滞模型。首先,利用Ansys软件对传统性能测试装置的传动系统在不同扭矩范围内进行了静态仿真分析,得到了相应的同轴度误差。其次,通过几何分析的方法建立了RV减速同轴度-几何迟滞模型,并结合Adams动力学仿真软件,在模型传动系统同轴度处于不同误差范围且无负载的情况下进行了动力学仿真分析。同轴度在允许误差范围内时,滞后值为0.5467 arcmin,结果表明该模型的准确性得到了验证。同时,当同轴度超过误差允许范围时,会对磁滞产生很大影响。该结果对分析高精度RV减速器性能检测装置同轴度误差的影响和调节机构的设计具有一定的理论意义和实用价值。
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引用次数: 2
Nonlinear characteristics of the driving model of the coaxial integrated macro–micro composite actuator 同轴集成宏微复合作动器驱动模型的非线性特性
IF 1.4 4区 工程技术 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-10-12 DOI: 10.5194/ms-13-843-2022
Caofeng Yu, Yu Wang, Zhihao Xiao, Ganyong Wu, Yongyong Duan, Kun Yang
Abstract. Nonlinearity is one of the important factors affecting thepositioning accuracy of the macro–micro composite actuator. To improve thepositioning accuracy of the driving model of the macro–micro compositeactuator, this paper combines the research phenomenon of the nonlinearcharacteristics of the voice coil motor to model the nonlinear factors thataffect the macro-moving part of the macro–micro composite actuator. Firstly,based on analyzing its structure and working principle, the variation law ofthe magnetic field intensity at the working air gap of the macro-motion partis analyzed by the finite element method, and the driving force model of themacro-motion part is established. Secondly, through the magnetic fieldsimulation analysis, there is a magnetization phenomenon in the mover part,and the static friction model is established. Then, the experimental data areacquired and processed by building the experimental test platform of theactuator, and the variation model of the electromechanical time constantwith the macro-motion displacement is established. Then, combined with theStribeck model and the static friction model, the kinetic model of themacro-motion part is established. Finally, using the least square methodidentify the parameter model, the results are compared with theexperiment. The results show that the magnetic field distribution at theworking air gap of the macro-motion part of the macro–micro compositeactuator is relatively uniform, but it is related to the macro-motiondisplacement and the macro-motion coil current. When the macro-motion partof the macro-micro composite actuator starts, the friction model canapproximately reflect the change of friction force, the kineticmodel of the macro-motion part can reflect the dynamic characteristics ofthe macro-motion part, and the matching degree is 92.97 %. The researchresults lay a theoretical and technical foundation for the development of ahigh-speed and large-stroke positioning controller of the macro-motion microcomposite actuator.
摘要非线性是影响宏微复合作动器定位精度的重要因素之一。为了提高宏微复合作动器驱动模型的定位精度,本文结合音圈电机非线性特性的研究现象,对影响宏微复合作动器宏观运动部分的非线性因素进行建模。首先,在分析其结构和工作原理的基础上,采用有限元法分析了大运动部件工作气隙处磁场强度的变化规律,建立了大运动部件的驱动力模型;其次,通过磁场仿真分析,发现动件存在磁化现象,并建立了静摩擦模型。然后,通过搭建作动器实验测试平台,对实验数据进行采集和处理,建立机电时间常数随宏观运动位移的变化模型。然后,结合stribeck模型和静摩擦模型,建立了大运动部件的动力学模型。最后,利用最小二乘法对参数模型进行辨识,并与实验结果进行了比较。结果表明:宏微复合作动器宏运动部分工作气隙处磁场分布相对均匀,但与宏运动位移和宏运动线圈电流有关;宏微复合作动器宏运动部分启动时,摩擦模型能近似反映摩擦力的变化,宏运动部分的动力学模型能反映宏运动部分的动态特性,匹配度为92.97%。研究结果为宏动微复合作动器的高速大行程定位控制器的研制奠定了理论和技术基础。
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引用次数: 0
Dynamic modeling and experiment of hind leg swimming of beaver-like underwater robot 类海狸水下机器人后腿游泳动力学建模与实验
IF 1.4 4区 工程技术 Q4 ENGINEERING, MECHANICAL Pub Date : 2022-10-10 DOI: 10.5194/ms-13-831-2022
Gang Chen, Zhenyu Wang, Jiajun Tu, Donghai Wang
Abstract. When the beaver-like underwater robot is swimming, its hind legs provide themain propulsion force for the body, which is the source of power for therobot's movement. Hind leg swimming dynamics is the basis for analyzing thegeneration and change of propulsion force during the robot swimming process,which directly determines how the robot swimming trajectory is planned.However, there are few researches on the swimming dynamics of the hind legof a beaver-like underwater robot. This paper proposes a rigid–liquid fusiondynamics modeling method, which simplifies the swimming dynamics of hindlegs of beaver-like robot to hydrodynamics of webbed feet and rigid bodydynamics of thighs and calves. The hydrodynamics of the bendable webbed foot isestablished based on the integral hydrodynamics method, and the rigid bodydynamic model of the thigh and calf is constructed using the Newton–Eulermethod. Through the force transmission, the overall swimming dynamic modelof the hind leg is established, and the propulsion and lift force of the hind legto body are obtained. The ANSYS Fluent simulation of the movement of robot'shind leg and underwater single-leg swimming experiments verify thecorrectness and effectiveness of the dynamics model. Comparing the theory,simulation, and experimental results of the propulsion and lift force of therobot's hind legs under bionic swimming, increased amplitude swimming, andreduced amplitude swimming, it further verifies the correctness of theproposed rigid–liquid fusion dynamic modeling method, and proves thesuperiority of the robot's bionic swimming trajectory. This study canprovide new ideas for the leg dynamic modeling of underwater swimming robotswith bendable webbed feet, and lay a theoretical foundation for exploringthe swimming mechanical process of underwater robots.
摘要当类似海狸的水下机器人游泳时,它的后腿为身体提供主要的推动力,这是机器人运动的动力来源。后肢游泳动力学是分析机器人游泳过程中推进力产生和变化的基础,它直接决定了机器人游泳轨迹的规划。然而,关于类海狸水下机器人后肢的游泳动力学研究却很少。本文提出了一种刚性-液体融合动力学建模方法,将类海狸机器人后腿的游泳动力学简化为蹼足的流体动力学和大腿和小腿的刚体动力学。基于积分流体力学方法建立了可弯曲腹板足的流体力学模型,并采用牛顿-欧拉方法建立了大腿和小腿的刚体动力学模型。通过力的传递,建立了后肢的整体游泳动力学模型,得到了后肢对身体的推进力和升力。ANSYS Fluent对机器人单腿和水下单腿游泳实验的运动进行了仿真,验证了动力学模型的正确性和有效性。通过比较仿生游泳、增幅游泳和减幅游泳条件下机器人后腿的推进力和升力的理论、仿真和实验结果,进一步验证了所提出的刚性-液体融合动力学建模方法的正确性,证明了机器人仿生游动轨迹的优越性。本研究可为可弯曲蹼足水下游泳机器人的腿部动力学建模提供新的思路,为探索水下机器人的游泳力学过程奠定理论基础。
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引用次数: 0
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Mechanical Sciences
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