反恐防暴机器人机构与控制的研究

西方国家早在20世纪60年代就开始采用防暴机器人处理爆炸物。自从9.11事件后，国际社会恐怖活动更是愈演愈烈，许多国家相继对此给予了高度重视。反恐防暴机器人可应用于核工业、军事、燃化、铁路、公安、武警等部门，代替人在危险、恶劣、有害环境中执行探查、排除或销毁爆炸物、消防、抢救人质以及与恐怖分子对抗等任务。本项目依托课题由最初的“危险作业机器人”到现在的“反恐防暴机器人的产业化研究”，由国家“863”计划资金滚动支持。就现有的反恐防暴机器人，存在速度较慢或机动灵活性不强或可靠性不高等不足，现研究出一种新型反恐防暴机器人，目的是在保证适应一定的非结构环境的前提下（适用所有的非结构环境的移动机构设计是不可取的，也是不现实的），提高机器人本体转向性能和移动速度，降低功耗，机构简单化，同时在硬件与软件设计时采取一些相应的措施，提高其在实际应用环境中的可靠性和抗干扰能力。首先，通过对以往反恐防暴机器人在非结构环境中采用的复合移动机构对比分析研究，提出了一种新型的轮-履带-腿复合移动机构，应用在”灵豹”机器人上。它的特色是移动机构继承了“灵蜥”系列反恐防暴机器人轮与履带移动方式自动切换功能，并且针对“灵蜥”系列机器人轮式移动时，四轮滑动转向灵活性不高、功耗大的问题，提出了三轮式移动机构，在狭小移动空间有着广泛的应用。并对该机器人本体做了运动学分析和稳定性分析，论证了该机构的可行性。其次，根据课题项目研究的需要，在控制方面，主要完成了“灵狐”小型反恐防暴机器人的系统构建与功能实现。通过从事“灵蜥”系列机器人项目开发，积累了一些移动机构设计与分析以及控制系统一些问题解决的实际经验，在“灵狐”控制系统设计过程中，由于采用单片机作为微控制单元，因此着重考虑了提高系统可靠性与抗干扰能力。在“灵狐”机器人样机试验中取得了好的效果，均达到预期目标。

新型轮—腿—履带复合移动机构及稳定性分析

为提高反恐防暴机器人对非结构环境的适应能力,设计出了一种具有良好的机动性能和转向性能的新型轮—腿—履带复合移动机构.通过机器人机构分析与本体的稳定性分析,论证了其结构设计的可行性及好的稳定性.

Effects of Graphitization on the Synthesis of Ultrafine Diamond by Explosive Detonation

金刚石的石墨化对于炸药爆轰过程中金刚石的产出率有重要的影响。对碳相图进行了讨论,提出采用金刚石2石墨的动力学平衡线来评价炸药爆轰过程中金刚石的石墨化。通过数值模拟,对炸药爆轰过程中金刚石的石墨化进行了分析和讨论。

Explosive consolidation of amorphous cobalt-based alloys

This paper addresses the explosive consolidation of amorphous cobalt-based alloys. Using the experimental setup introduced in the present paper, specimens with high compact density, excellent magnetic properties and great wearability have been made. In comparison with permalloy and ferrite, the present specimens exhibit superior magnetic properties. Therefore, the compact is deemed as being a promising material for magnetic recording heads.

Non-die explosive forming of spherical pressure-vessels

This paper presents a newly developed method of manufacturing spherical pressure vessels based on the technology of non-die explosive forming. Compared with the traditional method, this technology does not need any dies and pressing equipment, so that the cost of the production process can be greatly reduced, especially for vessels of less than 100 m3 capacity.

A study of the mechanism of consolidating metal-powder under explosive-implosive shock-waves

A study of the two-dimensional flow pattern of particles in consolidation process under explosive-implosive shock waves has been performed to further understand the mechanism of shock-wave consolidation of metal powder, in which bunched low-carbon steel wires were used instead of powder. Pressure in the compact ranges from 6 to 30 GPa. Some wires were electroplated with brass, some pickled. By this means, the flow pattern at particle surfaces was observed. The interparticle bonding and microstructure have been investigated systematically for the consolidated specimens by means of optical and electron microscopy, as well as by microhardness. The experimental results presented here are qualitatively consistent with Williamson's numerical simulation result when particle arrangement is close packed, but yield more extensive information. The effect of surface condition of particle on consolidation quality was also studied in order to explore ways of increasing the strength of the compacts. Based on these experiments, a physical model for metal powder shock consolidation has been established.

Failure process analysis of cement under explosive loading with a generalized driven nonlinear threshold model

The microstructural heterogeneity and stress fluctuation play important roles in the failure process of brittle materials. In this paper, a generalized driven nonlinear threshold model with stress fluctuation is presented to study the effects of microstructural heterogeneity on continuum damage evolution. As an illustration, the failure process of cement material under explosive loading is analyzed using the model. The result agrees well with the experimental one, which proves the efficiency of the model.

Measurement of the inelastic branch of the O-14(alpha, p)F-17 reaction: Implications for explosive burning in novae and x-ray bursters

A measurement of the inelastic component of the key astrophysical resonance in the 14O(α,p)17F reaction for burning and breakout from hot carbon-nitrogen-oxygen (CNO) cycles is reported. The inelastic component is found to be comparable to the ground-state branch and will enhance the 14O(α,p)17F reaction rate. The current results for the reaction rate confirm that the 14O(α,p)17F reaction is unlikely to contribute substantially to burning and breakout from the CNO cycles under novae conditions. The reaction can, however, contribute strongly to the breakout from the hot CNO cycles under the more extreme conditions found in x-ray bursters.

Measurement of the inelastic branch of the stellar O-14(alpha,p)F-17 reaction occurring in the explosive burning in Novae and X-ray busters

The inelastic component of the key astrophysical resonance (1(-), E-x=6.15 MeV) in the O-14(alpha,p)F-17 reaction has been studied by using the resonant scattering of F-17+p. The experiment was done at REX-ISOLDE CERN with the Miniball setup. The thick target method in inverse kinematics was utilized in the present experiment where a 44.2 MeV F-17 beam bombarded a similar to 40 mu m thick (CH2)(n) target. The inelastic scattering protons in coincidence with the de-excited 495 keV gamma rays have been clearly seen and they are from the inelastic branch to the first excited state in F-17 following decay of the 1(-) resonance in Ne-18. Some preliminary results are reported.

Detection and Characterization of Long-Pulse Low-Velocity Impact Damage in Plastic Bonded Explosives

Damage not only degrades the mechanical properties of explosives, but also influences the shock sensitivity, combustion and even detonation behavior of explosives. The study of impact damage is crucial in the vulnerability evaluation of explosives. A long-pulse low-velocity gas gun with a gas buffer was developed and used to induce impact damage in a hot pressed plastic bonded explosive. Various methods were used to detect and characterize the impact damage of the explosive. The microstructure was examined by use of polarized light microscopy. Fractal analysis of the micrographs was conducted by use of box counting method. The correlation between the fractal dimensions and microstructures was analyzed. Ultrasonic testing was conducted using a pulse through-transmission method to obtain the ultrasonic velocity and ultrasonic attenuation. Spectra analyses were carried out for recorded ultrasonic signals using fast Fourier transform. The correlations between the impact damage and ultrasonic parameters including ultrasonic velocities and attenuation coefficients were also analyzed. To quantitatively assess the impact induced explosive crystal fractures, particle size distribution analyses of explosive crystals were conducted by using a thorough etching technique, in which the explosives samples were soaked in a solution for enough time that the binder was totally removed. Impact induces a large extent of explosive crystal fractures and a large number of microcracks. The ultrasonic velocity decreases and attenuation coefficients increase with the presence of impact damage. Both ultrasonic parameters and fractal dimension can be used to quantitatively assess the impact damage of plastic bonded explosives.

Johnson-Cook材料模型参数的实验测定

介绍了一种通过Hopkinson拉伸实验、圆筒爆炸试验和计算机仿真来确定Johnson-Cook材料模型中相关常数的方法。

Source Model for Blasting Vibration

By analyzing and comparing the experimental data, the point source moment theory and the cavity theory, it is concluded that the vibrating signals away from the blasting explosive come mainly from the natural vibrations of the geological structures near the broken blasting area. The source impulses are not spread mainly by the inelastic properties (such as through media damping, as believed to be the case by many researchers) of the medium in the propagation pass, but by this structure. Then an equivalent source model for the blasting vibrations of a fragmenting blasting is proposed, which shows the important role of the impulse of the source's time function under certain conditions. For the purpose of numerical simulation, the model is realized in FEM, The finite element results are in good agreement with the experimental data.

Spherical nanometer-sized diamond obtained from detonation

Ultrafine diamond (UFD) was synthesized under high pressure and high temperatures generated by explosive detonation. The structure, composition, surface and thermal stability of UFD were studied by use of XRD, TEM, Raman Spectroscopy, FTIR, etc. The influences of the synthesis conditions and purification conditions on the properties of UFD were analyzed. The UFD had an average size of 4-6 nm, commonly exhibiting a spherical shape. The highest yield was of up to 10 mass% of the explosive. Attempts were made to use UFD as an additive to metal-diamond sintering and as crystallite seeds of CVD diamond films. The results show that UFD can decrease the coefficient of friction of the composite by 30%, and raise the nucleation density in CVD diamond films by 2-3 times.