Name: measurement of the hand transmitted vibration of the human hand arm system during operation of a hand tractor
Uploaded: 2021-06-16T14:00:00
Description: Watch this Scientific Journal Video about Measurement of the Hand Transmitted Vibration of the Human Hand Arm System During Operation of a Hand Tractor at JoVE.com

这项工作得到了中国重庆市自然科学基金（cstc2019jcyj-msxmX0046）、重庆市教委（KJQN2002001127）项目和中国重庆市巴南区科委（2020TJZ010）项目的支持。作者要感谢杨燕教授提供试验场。我们也感谢王景树博士和马景华博士指导使用振动测量仪器。感谢受试者在实验期间的全心合作。

所有程序均经重庆理工大学伦理委员会批准，各学科在参与本研究前均提供书面知情同意。
1. 手扶拖拉机准备
<ol><li>确保手扶拖拉机在充分的燃油箱下接受适当的测试，没有螺栓松动，并且不会产生其他可能导致异常振动的机械缺陷。 注：本实验中使用的手扶拖拉机的规格在 表1中给出。</li>
	<li>将手扶拖拉机放置在具有干燥、坚固和平地表面的试验场。 ?...

<ol>
	<li>Ahmadian, H., Hassan-Beygi, S. R., Ghobadian, B., Najafi, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ANFIS+modeling+of+vibration+transmissibility+of+a+power+tiller+to+operator.">ANFIS modeling of vibration transmissibility of a power tiller to operator.</a> Applied Acoustics. 138, 39-51 (2018).</li><li>Heaver, C., Goonetilleke, K. S., Ferguson, H., Shiralkar, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hand-arm+vibration+syndrome:+a+common+occupational+hazard+in+industrialized+countries.">Hand-arm vibration syndrome: a common occupational hazard in industrialized countries.</a> Journal of Hand Surgery. 36 (5), 354-363 (2011).</li><li>Geethanjali, G., Sujatha, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Study+of+Biomechanical+Response+of+Human+Hand-Arm+to+Random+Vibrations+of+Steering+Wheel+of+Tractor.">Study of Biomechanical Response of Human Hand-Arm to Random Vibrations of Steering Wheel of Tractor.</a> Molecular &amp; Cellular Biomechanics. 10 (4), 303-317 (2013).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ISO+5349-1:+Mechanical+Vibration:+Measurement+and+Evaluation+of+Human+Exposure+to+Hand+Transmitted+Vibration+Part+1:+General+requirements.">ISO 5349-1: Mechanical Vibration: Measurement and Evaluation of Human Exposure to Hand Transmitted Vibration Part 1: General requirements.</a> International Organization for Standardization. , (2001).</li><li>International Organization for Standardization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ISO5349-2:+Mechanical+vibration-+Measurement+and+evaluation+of+human+exposure+to+hand-transmitted+vibration.+Part+2:+Practical+guidance+for+measurement+at+the+workplace.">ISO5349-2: Mechanical vibration- Measurement and evaluation of human exposure to hand-transmitted vibration. 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L., Carballeira, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterisation+of+the+mechanical+impedance+of+the+human+hand-arm+system:+The+influence+of+vibration+direction,+hand-arm+posture+and+muscle+tension.">Characterisation of the mechanical impedance of the human hand-arm system: The influence of vibration direction, hand-arm posture and muscle tension.</a> International Journal of Industrial Ergonomics. 37 (3), 225-231 (2007).</li><li>Marcotte, P., Aldien, Y., Boileau, P. &. #. 2. 0. 1. ;., Rakheja, S., Boutin, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+handle+size+and+hand-handle+contact+force+on+the+biodynamic+response+of+the+hand-arm+system+under+zh-axis+vibration.">Effect of handle size and hand-handle contact force on the biodynamic response of the hand-arm system under zh-axis vibration.</a> Journal of Sound and Vibration. 283 (3-5), 1071-1091 (2005).</li><li>Pan, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relationships+between+hand+coupling+force+and+vibration+biodynamic+responses+of+the+hand-arm+system.">The relationships between hand coupling force and vibration biodynamic responses of the hand-arm system.</a> Ergonomics. 61 (6), 818-830 (2018).</li><li>Dong, R. 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S., Velmurugan, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+handle+shape+and+size+to+reduce+the+hand-arm+vibration+discomfort.">Influence of handle shape and size to reduce the hand-arm vibration discomfort.</a> Work. 63 (3), 415-426 (2019).</li><li>Dewangan, V. K. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characteristics+of+hand-transmitted+vibration+of+a+hand+tractor+used+in+three+operational+modes.">Characteristics of hand-transmitted vibration of a hand tractor used in three operational modes.</a> International Journal of Industrial Ergonomics. 39 (1), 239-245 (2009).</li><li>Kalra, M., Rakheja, S., Marcotte, P., Dewangan, K. N., Adewusi, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+coupling+forces+at+the+power+tool+handle-hand+interface.">Measurement of coupling forces at the power tool handle-hand interface.</a> International Journal of Industrial Ergonomics. 50, 105-120 (2015).</li><li>Gurram, R., Rakheja, S., Gouw, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+study+of+hand+grip+pressure+distribution+and+EMG+of+finger+flexor+muscles+under+dynamic+loads.">A study of hand grip pressure distribution and EMG of finger flexor muscles under dynamic loads.</a> Ergonomics. 38 (4), 684-699 (1995).</li><li>Tarabini, M., Saggin, B., Scaccabarozzi, D., Moschioni, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hand-arm+mechanical+impedance+in+presence+of+unknown+vibration+direction.">Hand-arm mechanical impedance in presence of unknown vibration direction.</a> International Journal of Industrial Ergonomics. 43 (1), 52-61 (2013).</li><li>Aatola, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transmission+of+vibration+to+the+wrist+and+comparison+of+frequency+response+function+estimators.">Transmission of vibration to the wrist and comparison of frequency response function estimators.</a> Journal of Sound and Vibration. 131 (3), 497-507 (1989).</li><li>Kihlberg, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodynamic+response+of+the+hand-arm+system+to+vibration+from+an+impact+hammer+and+a+grinder.">Biodynamic response of the hand-arm system to vibration from an impact hammer and a grinder.</a> International Journal of Industrial Ergonomics. 16 (1), 1-8 (1995).</li><li>Gurram, R., Rakheja, S., Gouw, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vibration+transmission+characteristics+of+the+human+hand-arm+and+gloves.">Vibration transmission characteristics of the human hand-arm and gloves.</a> International Journal of Industrial Ergonomics. 13 (3), 217-234 (1994).</li><li>Burstr&#246;m, A. S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transmission+of+vibration+energy+to+different+parts+of+the+human+hand-arm+system.">Transmission of vibration energy to different parts of the human hand-arm system.</a> Int Arch Occup Environ Health. 70 (3), 199-204 (1997).</li><li>Hartung, E., Dupuis, H., Scheffer, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+grip+and+push+forces+on+the+acute+response+of+the+hand-arm+system+under+vibrating+conditions.">Effects of grip and push forces on the acute response of the hand-arm system under vibrating conditions.</a> International Archives of Occupational and Environmental Health. 64 (6), 463-467 (1993).</li><li>Pope, M. 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本研究提出的协议是根据HTV标准4、5、24建立的，是作为在固定条件下手扶拖拉机运行过程中测量人手扶手系统HTV的标准步骤而制定的。这种情况是手牵引机最稳定的状态，有助于确保可靠测量实际传送到手和手臂的振动。通过调整发动机速度和抓地力，考虑执行测试的变量范围涵盖了手牵引车的正常和安全操作范围。考虑到?...

手扶拖拉机，也称为动力耕作机，广泛用于发展中国家小田的土地准备。手扶拖拉机的现场操作包括走在机器后面，握住手柄控制机器的移动。手扶拖拉机的操作员暴露在高振动水平，这可以归因于小型单缸发动机和缺乏悬挂系统的手牵引1。手臂振动综合征 （HAVS）2 可由振动引起的长期耐久性（称为手部传动振动 （HTV），由手牵引器生成，由操作员手接收。为了评估操作员接触手扶拖拉机HTV所带来的健康风险，有必要建立手扶手系统振动响应测量方法。
手臂系统由骨骼、肌肉、组织、静脉和动脉、肌腱和皮肤3组成，直接测量HTV会带来许多问题。相关国际标准4、5提供有关测量手附近振动严重程度的指引，包括手部坐标系、加速度计的位置和安装、测量持续时间、电缆连接器问题等。然而，标准没有考虑到内在变量，如抓地力，手和手臂的姿势，个别因素等。这些因素在广泛的振动激发和测试条件下进行了广泛的研究，6、7、8、9、10、11、12、13，但不同的研究结果并不完全一致。其中许多因素没有得到充分理解，无法纳入标准方法。这一限制部分归因于人类手臂系统的复杂性、试验条件以及所采用的实验和测量技术的差异。
此外，HTV的早期测量大多在经过严格控制的条件下进行，具有理想的振动激发、抓地力和姿势条件。因此，这些测量结果和实验程序可能无法真正复制实际情况，例如手扶拖拉机的运行条件。此外，只有有限的努力来研究手牵引车的HTV与现场测量。这些测量是使用附加在操作员的手腕、手臂、胸部和头部的加速度计进行的，以测量拖拉机运输条件下的全身振动1，或在耕种在耕种场和在发动机速度14级不同级别的水下田地中呕吐的条件下进行。抓地力的作用，这可能是HTV7，8的关键因素，并没有孤立。因此，由于经营者在耕作过程中由于恶劣的环境条件而采取各种强制姿势，这些方法不适合作为标准化的测量程序。
本研究旨在为以固定模式对手扶拖拉机进行HTV测量建立可靠和可重复的程序作出贡献。图1显示实验设计的示意图图。采用了中国制造、中国农民常用的手扶拖拉机，并选派了10名科研人员作为研究对象。七台连接到拖拉机手臂系统的轻型压电加速度计用于测量振动。一个测速仪和两个薄膜压力传感器在测试期间监测发动机速度和抓地力。受试者必须按规定发动机速度和指定的抓地力按顺序操作手扶拖拉机，以获得各种操作模式的振动特性。本手稿为拖拉机手臂系统的 HTV 测量提供了详细的协议，并特别考虑了抓地力和振动频率的变化。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Accelerometers</td>
			<td>PCB Piezotronics Inc.</td>
			<td>352C33, 356A04</td>
			<td>Used to measure vibration signals. Including 2 tri-axial accelerometers and 5 single-axis accelerometers.</td>
		</tr>
		<tr>
			<td>CompactDAQ System</td>
			<td>National Instruments</td>
			<td>cRIO-9045,NI-9234 C</td>
			<td>Used for acceleration acquisition. The system consists of a chassis and 3 data acquisition cards.</td>
		</tr>
		<tr>
			<td>Digital caliper</td>
			<td>Sanliang</td>
			<td>160800635</td>
			<td>Used to measure dimensions of the hand.</td>
		</tr>
		<tr>
			<td>Digital goniometer</td>
			<td>Sanliang</td>
			<td>802973</td>
			<td>Used to measure hand and arm posture.</td>
		</tr>
		<tr>
			<td>Laptop computer</td>
			<td>Lenovo</td>
			<td>Ideapad 500s</td>
			<td>To run the softwares.</td>
		</tr>
		<tr>
			<td>Matlab</td>
			<td>MathWorks Inc.</td>
			<td>Version 2020a</td>
			<td>Used for data processing.</td>
		</tr>
		<tr>
			<td>NI SignalExpress</td>
			<td>National Instruments</td>
			<td>Trial version 2015</td>
			<td>Use to acquire, analyze and present acceleration data.</td>
		</tr>
		<tr>
			<td>Tachometer</td>
			<td>Sanliang</td>
			<td>TM 680</td>
			<td>Used to measure engine speed.</td>
		</tr>
		<tr>
			<td>Thin-film pressure sensing system</td>
			<td>YourCee</td>
			<td>n/a</td>
			<td>Used to measure grip force. The system consists of 2 thin-film sensors, a STM32 singlechip and a LED display.</td>
		</tr>
	</tbody>
</table>

measurement of the hand transmitted vibration of the human hand arm system during operation of a hand tractor

手牵引机的操作员暴露在高水平的手传振动 （HTV） 中。这种振动既令人讨厌又对人体健康有害，通过他或她的手和手臂传授给操作员。然而，衡量手扶拖拉机HTV的标准化方法尚未确定。研究的目的是提出一种实验方法，用于研究手扶拖拉机在静止模式下操作过程中手臂系统的生物动力反应和振动可传播性。用三个抓地力和三个手柄振动水平对十个受试者进行测量，以检查手部压力和频率对手部传导振动 （HTV） 的影响。结果表明，手柄的紧握会影响手臂系统的振动响应，尤其是在 20 至 100 Hz 之间的频率。手臂系统中较低频率的传输相对没有减弱。相比之下，在手牵引车操作过程中，衰减频率较高。随着与振动源距离的增加，手臂系统不同部分的振动可传输性降低。拟议的方法有助于收集一致的数据，用于评估操作员振动暴露和手扶拖拉机的人体工程学发展。

实验是在实验室进行（空气温度22.0°C±1.5°C）的10个健康受试者（表2）在手扶拖拉机的操作中处于静止状态。
按照协议，从手牵引车的手柄以及手背、手腕、手臂和每个主体的肩膀收集振动加速数据。获取了手柄（输入到手部）时发生的振动加速度谱。 图 8 在给定时间内，在发动机速度级别为 3500 rpm 时柄上显示时间域和 RMS 频率域加速度?...

Watch this Scientific Journal Video about Measurement of the Hand Transmitted Vibration of the Human Hand Arm System During Operation of a Hand Tractor at JoVE.com

Measurement of the Hand Transmitted Vibration of the Human Hand Arm System During Operation of a Hand Tractor

在这里，我们提出了一种标准化的方法，用于测量单轴牵引车手柄的手传振动，并特别参考了抓地力和振动频率的变化。

手牵引机运行过程中人手臂系统手传振动的测量

Operators of hand tractors are exposed to high levels of hand transmitted vibration (HTV). This vibration, which can be both irksome and hazardous to ...

本实验的总体目标是研究手扶拖拉机运行过程中手臂系统的生物动力反应和振动可传播性。本研究为牵引手臂系统的手传振动测量提供了一个协议，并考虑了抓地力和振动频率的变化。这种方法将有助于理解手臂系统的振动传输特性。首先，将手扶拖拉机放置在干燥、坚固且平地表面的试验场。取出手柄的弹性材料。在获得所有受试者知情同意后，测量每个受试者的身体尺寸，包括站立高度、质量、前臂长度、上臂长度和手长。将加速度计适配器紧紧包裹在每个主体的手和手臂上。每个适配器都是用尼龙带和一块镀锌铁板制造的，以提供刚性和轻的附件。加速度计适配器被包裹在手背的位置，前臂的离位，前臂的近端，上臂的离位，上臂的近端和腹臂。在开始测量之前，收集测量系统的所有组件，包括加速度计、数据采集系统、薄膜压力感应系统、转速计、数字气压计、加速度计适配器和其他相关组件。要设置加速度测量系统，首先，使用加速度计电缆，将加速度计与数据采集卡连接起来。使用以太网电缆，将底盘与计算机连接起来。然后，将一个三轴加速度计连接到左手柄或手牵引器上，并将另一个加速度计连接到受试者左手的加速度计适配器上。将单轴加速度计一个接一个地附在受试者手臂和肩部的加速度计适配器上。调整三轴加速度计的方向，以符合指定的坐标系。最后，使用胶带固定受试者手臂皮肤表面和拖拉机车把上的加速度计电缆。要建立抓地力测量系统，首先，使用双面胶带，在手牵引机的左手柄上安装两个薄膜传感器。然后，将屏幕系统放置在一个方便的高度。以便受试者在手牵引器操作期间能够监控并将抓地力调整到指定级别。之后，指示主体将手柄保持并提升到水平位置。使用数字妖精测量受试者的手和手臂姿势，包括肩部水平诱拐、肩部垂直诱拐、肘部伸展、手腕伸长和手腕偏差。要求受试者保持姿势，直到审判结束。以中性启动手牵引机，并保持低发动机速度运行，直到其稳定下来。打开测速仪、薄膜压力感应装置、笔记本电脑和加速数据采集系统。设置数据收集的加速参数、采集模式和采样率。单击"运行"，等待大约十秒钟，直到系统稳定下来，然后单击"记录"开始记录加速数据。在测试过程中，要求受试者监控转速计，并将发动机速度调整到每分钟 1，500 转，直到其稳定下来。然后，指示受试者将抓地力仔细调整到 20 牛顿，并将抓地力水平保持在大约 30 秒。接下来，将抓地力调整到30牛顿，并保持约30秒。然后，将抓地力调整到 40 牛顿，并保持约 30 秒。之后，将发动机速度调整为每分钟 2，500 转，并重复上述抓地力调整程序。最后，将发动机速度调整为每分钟 3，500 转，并重复上述抓地力调整程序。试验结束时，指示受试者放下手柄，关闭手扶拖拉机的发动机。保存振动加速度数据，拆下并放置下一个主题的加速度计。重复上述步骤，直到所有受试者的数据收集结束。并导出加速时间系列数据供进一步分析。这些图在手柄上显示时间域和频率域加速度的示例，持续时间为半秒。X 和 Z 方向的最大加速度发生在 58 赫兹的频率下。发现大部分振动能量集中在频率范围从50到200赫兹。获得了手臂系统的抓地力与根均等方加速度之间的均等关系。观察到，抓地力的增加显著增加了赫兹20至100赫兹频率的振动加速度。并且发现三个共振频率几乎随着抓地力的增加而线性地增加。同时，也获得了发动机速度与根均平方加速度的关系。如图所示，较低的频率传输相对未受衰减。虽然，衰减是相当明显的更高频率。因此，可以合理地得出结论，大部分振动能量在手和前臂中消散。此图表示手臂系统不同位置的平均可传输性。结果发现，手臂系统的可传播性随着振动源距离的增加而降低。在手背观察到最高的可传播性。手腕和肘部可传播的共振频率约为20赫兹。还发现只有不到25赫兹的振动被有效地传送到前臂、上臂和肩膀。该方法是根据手部传动振动标准建立的，是作为在固定条件下手扶拖拉机运行过程中测量人手臂系统手部传动振动的标准方案而开发的。加速度计和适配器的总重量应尽可能轻，以减少测量误差。应不间断地完成每个科目的测试试验，以降低操作姿势的效果。建议方法的主要潜在应用是人-拖拉机相互作用现象的估计、手扶拖拉机的人体工程学发展以及隔离器和手套等保护装置的开发。

Research

JoVE Journal

Engineering

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

无约束和封闭表面活性剂中球形粒子沉降速度的实验测量 剪切变薄粘性流体

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic ...

科研

工程学

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

集成的三重态 - 三重态湮灭上转换系统，提高染料敏化太阳能电池的响应子带隙光

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents ...

Fabrication and Operation of a Nano-Optical Conveyor Belt

一个纳米光输送带的制作和操作

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological ...

Development of an Experimental Setup for the Measurement of the Coefficient of Restitution under Vacuum Conditions

实验装置的研制归还系数在真空条件下测量

The Discrete Element Method is used for the simulation of particulate systems to describe and analyze them, to predict and afterwards optimize their ...

The Measurement of Unsteady Surface Pressure Using a Remote Microphone Probe

非定常表面压力的使用远程麦克风探头测量

Microphones are widely applied to measure pressure fluctuations at the walls of solid bodies immersed in turbulent flows. Turbulent motions with various ...

Hand Controlled Manipulation of Single Molecules via a Scanning Probe Microscope with a 3D Virtual Reality Interface

通过手扫描探针显微镜用三维虚拟现实接口控制单分子的操作

Considering organic molecules as the functional building blocks of future nanoscale technology, the question of how to arrange and assemble such building ...

Generation of Size-controlled Poly (ethylene Glycol) Diacrylate Droplets via Semi-3-Dimensional Flow Focusing Microfluidic Devices

Generation of Size-controlled Poly ethylene Glycol Diacrylate Droplets via Semi-3-Dimensional Flow Focusing Microfluidic Devices

Semi-3-Dimensional 流聚焦微流控装置产生尺寸控制的聚乙二醇二丙烯酸酯液滴

Uniform and size-controllable poly (ethylene glycol) diacrylate (PEGDA) droplets could be produced via the flow focusing process in a microfluidic device. ...

Construction and Operation of a Light-driven Gold Nanorod Rotary Motor System

轻型金纳米旋转电机系统的施工与运行

The possibility to generate and measure rotation and torque at the nanoscale is of fundamental interest to the study and application of biological and ...

Fabrication of Soft Pneumatic Network Actuators with Oblique Chambers

斜腔软气动网络驱动器的研制

Soft pneumatic network actuators have become one of the most promising actuation devices in soft robotics which benefits from their large bending ...

Operation of the Collaborative Composite Manufacturing (CCM) System

Operation of the Collaborative Composite Manufacturing CCM System

协同复合制造 （CCM） 系统的操作

The automated tape placement and the automated fiber placement (AFP) machines provide a safer working environment and reduce the labor intensity of ...