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Numerical Analysis for Heat Shield Ablation Law in Transpiration Cooling System

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Journal of Thermal Science 1993年第4期2卷 260-265页

作者： xuyan－hou YangZhao－Ji DepartmentofModernMechanics UniversityofScienceandTechnologyofChinaHefer230026China DepartmentofMod

The transpiration cooling control system of the thermal protective shield with surface ablation is a nonlinear control system of distributed parameter with moving *** far as the boundary conditions the third kind and a one-dimensional incompressible coolant flow under constant transpiration mass flux are concerned,this paper transforms the definite solution problem into the second-type Volterra integral equations,and applies them directly to compute the shield ablation *** of the system's control by transpiration mass flux,ablation amount and ablation velocity varying with time,time of the ablation's beginning and ending,etc.,are presented.

关键词： ablation transpiration cooling second-type Volterra integral equations distributed parameter control moving boundary

Development of a Drilling and Coring Test-bed for Lunar Subsurface Exploration and Preliminary Experiments

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 673-682页

作者： SHI Xiaomeng DENG Zongquan QUAN Qiquan TANG Dewei hou xuyan JIANG Shengyuan School of Mechatronics Engineering Harbin Institute of Technology

Drill sampling has been widely employed as an effective way to acquire deep samples in extraterrestrial exploration. A novel sampling method, namely, flexible-tube coring, was adopted for the Chang＇e mission to acquire drilling cores without damaging stratification information. Since the extraterrestrial environment is uncertain and different from the terrestrial environment, automated drill sampling missions are at risk of failure. The principles of drilling and coring for the lunar subsurface should be fully tested and verified on earth before launch. This paper proposes a test-bed for conducting the aforementioned experiments on earth. The test-bed comprises a rotary-percussive drilling mechanism, penetrating mechanism, drilling medium container, and signal acquisition and control system. For granular soil, coring experiments indicate that the sampling method has a high coring rate greater than 80%. For hard rock, drilling experiments indicate that the percussive frequency greatly affects the drilling efficiency. A multi-layered simulant composed of granular soil and hard rock is built to test the adaptability of drilling and coring. To tackle complex drilling media, an intelligent drilling strategy based on online recognition is proposed to improve the adaptability of the sampling drill. The primary features of this research are the proposal of a scheme for drilling and coring a test-bed for validation on earth and the execution of drilling experiments in complex media.

关键词： drilling and coring device test-bed lunar soil sampling

Identification of neutron-rich isotope ^(197)Os

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Nuclear Science and Techniques 2004年第5期15卷 265-267页

作者： YANGWei-Fan YUANShuang-Gui xuyan-Bing XIAOYong-hou ZHAOLi-Min WANGPing-Zhi LIHeng-Yuan InstituteofModernPhysics.theChineseAcademyofSciences Lanzhou730000

A new neutron-rich isotope 197Os was produced in the198Pt(n, 2p) reaction by irradiating natural Pt targets with 14 MeV neutrons. The γ(X) singles spectrum and coincidence spectrum measurements were performed using two HPGe γ-ray detectors. Ten unknown γ-rays at 41.2, 50.7, 196.8, 199.6, 223.9, 233.1, 250.2, 342.1, 403.6, and 460.4 keV attributed to the decay of 197Os were observed in the experiments. The half-life of 197Os was found to be (2.8 ± 0.6) min. A partial decay scheme of 197Os was proposed on the basis of decay and coincidence relations. The half-life was compared with the values expected by different theoretical models.

关键词： Os 半衰期同时测量法重同位素衰减图解

Bio-inspired Attachment Mechanism of Dynastes Hercules:Vertical Climbing for On-Orbit Assembly Legged Robots

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Journal of Bionic Engineering 2024年第1期21卷 137-148页

作者： Yuetian Shi xuyan hou Zhonglai Na Jie Zhou Nan Yu Song Liu Linbo Xin Guowei Gao Yuhui Liu School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

With the increasing size of space facilities,on-orbit assembly requires robots to move on different heights of *** paper proposes a bio-inspired attachment mechanism for robot feet to enable climbing on different heights of *** by the attachment and grasping abilities of Dynastes Hercules,we utilize its foot microstructures,such as microhooks and setae,to achieve efficient contact and firm grip with the *** morphology and arrangement of these structures can inspire the design of robot feet to improve their grasping and stability *** study the biological structure of Dynastes Hercules,design and optimize the bio-inspired structure,analyze the influence of various factors from theoretical and experimental perspectives,and verify the feasibility of the scheme through *** propose an ideal climbing strategy that provides useful reference for robot applications in ***,the influence laws of various factors in this paper can be applied to robot foot design to improve their operation ability and stability performance in the space *** bio-inspired mechanism can improve robot working range and efficiency,which is critical for on-orbit assemblyin space.

关键词： Space assembly robot Truss climbing Bionic structure Dynastes Hercules tarsus

Directional sliding of water:biomimetic snake scale surfaces

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Opto-Electronic Advances 2021年第4期4卷 35-46页

作者： Yizhe Zhao Yilin Su xuyan hou Minghui Hong Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3117576Singapore State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

Bioinspired superhydrophobic surfaces have attracted many industrial and academic interests in recent *** by unique superhydrophobicity and anisotropic friction properties of snake scale surfaces,this study explores the feasibility to produce a bionic superhydrophobic stainless steel surface via laser precision engineering,which allows the realization of directional superhydrophobicity and dynamic control of its water *** mechanism of water sliding on hierarchical snake scale structures is studied,which is the key to reproduce artificially bioinspired multifunctional materials with great potentials to be used for water harvesting,droplet manipulation,pipeline transportation,and vehicle acceleration.

关键词： biomimetic hierarchical micro/nanostructures directional superhydrophobicity anisotropic friction

一种用于运动目标捕获的行星轮差动式欠驱动臂

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北京航空航天大学学报 2016年第10期42卷 2198-2205页

作者：王清川全齐全邓宗全侯绪研哈尔滨工业大学机器人技术与系统国家重点实验室哈尔滨150001

为解决运动目标捕获过程中的碰撞问题,采用欠驱动自适应原理研制了具有碰撞能量吸收能力的机械臂。三自由度的机械臂由2个电机驱动:基关节由单个电机驱动;中关节和末关节由一个单输入双输出行星轮组完成动力分配。在机械臂捕获运动目标... 详细信息

为解决运动目标捕获过程中的碰撞问题,采用欠驱动自适应原理研制了具有碰撞能量吸收能力的机械臂。三自由度的机械臂由2个电机驱动:基关节由单个电机驱动;中关节和末关节由一个单输入双输出行星轮组完成动力分配。在机械臂捕获运动目标过程中,碰撞产生的部分冲击能量通过欠驱动行星轮组传递到末关节,转化为关节动能。依靠欠驱动机械系统完成对碰撞的响应,解决了控制系统因时延而无法快速对碰撞进行响应的难题。为完成对目标的抓取,基于阻抗控制提出了机械臂运动目标捕获控制算法。运动目标捕获实验验证了机械臂对碰撞的快速响应能力及运动目标捕获控制算法的可行性。

关键词：运动目标捕获欠驱动机械臂差动驱动行星齿轮阻抗控制

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轴孔协调接触建模与试验研究

哈尔滨工程大学学报 2016年第11期37卷 1546-1552页

作者：李云涛全齐全唐德威侯绪研哈尔滨工业大学机器人技术与系统国家重点实验室黑龙江哈尔滨150001

传统的轴孔接触解析模型通常研究轴与带孔无限大平面的接触问题,未考虑孔壁厚度对轴孔接触特性的影响。本文考虑孔壁厚度对轴孔接触特性的影响,基于Winkler弹性基础模型和几何约束条件,沿接触点的法线方向建立了轴孔协调接触解析模型。... 详细信息

传统的轴孔接触解析模型通常研究轴与带孔无限大平面的接触问题,未考虑孔壁厚度对轴孔接触特性的影响。本文考虑孔壁厚度对轴孔接触特性的影响,基于Winkler弹性基础模型和几何约束条件,沿接触点的法线方向建立了轴孔协调接触解析模型。分析轴孔协调接触模型发现,接触力和接触刚度受间隙和孔壁厚度影响较大。基于图像法开展的轴孔接触试验结果表明,轴孔的接触刚度随接触深度的增大呈现非线性增大的特征,而且与以往的轴孔静态接触模型相比,本文所建立的模型与试验数据的吻合程度较高,因而本文提出的接触模型能够准确描述轴孔的协调接触特性。

关键词：协调接触模型回转铰链几何约束弹性层图像法

月壤钻探采样装置中的钻杆结构参数优化设计及模拟试验

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机械工程学报 2012年第23期48卷 10-15页

作者：田野邓宗全唐德威姜生元侯绪研哈尔滨工业大学宇航空间机构及控制中心哈尔滨150001

对月球次表层钻取采样外螺旋钻杆的输土阻力进行理论分析。基于散体力学中连续介质假设,建立钻杆回转输土阻力矩模型。利用该模型分析钻杆直径、螺旋升角等结构参数与输土阻力矩变化的关系,给出参数选择范围。以钻杆输土所消耗的功率为... 详细信息

对月球次表层钻取采样外螺旋钻杆的输土阻力进行理论分析。基于散体力学中连续介质假设,建立钻杆回转输土阻力矩模型。利用该模型分析钻杆直径、螺旋升角等结构参数与输土阻力矩变化的关系,给出参数选择范围。以钻杆输土所消耗的功率为目标,以钻杆结构参数为变量,对钻杆结构参数进行优化设计,使优化后的钻杆平均输土功率降低了30.5%。对结构优化后的钻杆输土阻力进行测试试验,验证了钻杆输土阻力矩随深度增加而变大的趋势。研究成果能为月球次表层采样钻杆设计提供理论依据。

关键词：钻取采样钻杆结构参数阻力矩模型优化试验

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模拟月壤钻进力载建模及试验验证

机械工程学报 2017年第7期53卷 85-93页

作者：唐钧跃全齐全姜生元侯绪研邓宗全哈尔滨工业大学机器人技术与系统国家重点实验室哈尔滨150001

我国探月三期工程无人自主采样任务将利用钻取采样的方式获取深层月壤样品。由于不同月壤组分的机械特性存在显著差异,且采样点处沿深度方向月壤组分分布具有随机性,钻进过程中采样装置所受钻进负载极有可能发生剧烈波动,严重影响钻进... 详细信息

我国探月三期工程无人自主采样任务将利用钻取采样的方式获取深层月壤样品。由于不同月壤组分的机械特性存在显著差异,且采样点处沿深度方向月壤组分分布具有随机性,钻进过程中采样装置所受钻进负载极有可能发生剧烈波动,严重影响钻进稳定性。为保证采样任务的顺利实施,采样装置需要在有限的钻进功耗和钻压力条件下,及时调整合适的钻进工艺参数,控制钻进负载在合理范围内,降低采样风险。分析钻具作用下月壤的失效形式及运移状态,提出填充率概念用以定量描述螺旋钻杆的排屑状况,基于螺旋输送理论建立两种典型工况下的钻进力载模型。多维钻进工艺参数下的模拟月壤钻进试验表明:填充率指标能够准确描述螺旋钻杆的排屑状况;钻进力载模型能够有效预测钻进负载。

关键词：月面钻取采样钻进负载填充率钻进工艺参数