Soft Robotics: Morphology and Morphology-inspired Motion Strategy

Robotics has aroused huge attention since the 1950s. Irrespective of the uniqueness that industrial applications exhibit, conventional rigid robots have displayed noticeable limitations, particularly in safe cooperation as well as with environmental adaption. Accordingly, scientists have shifted their focus on soft robotics to apply this type of robots more effectively in unstructured environments. For decades, they have been committed to exploring sub-fields of soft robotics (e.g., cutting-edge techniques in design and fabrication, accurate modeling, as well as advanced control algorithms). Although scientists have made many different efforts, they share the common goal of enhancing applicability. The presented paper aims to brief the progress of soft robotic research for readers interested in this field, and clarify how an appropriate control algorithm can be produced for soft robots with specific morphologies. This paper, instead of enumerating existing modeling or control methods of a certain soft robot prototype, interprets for the relationship between morphology and morphology-dependent motion strategy, attempts to delve into the common issues in a particular class of soft robots, and elucidates a generic solution to enhance their performance.      

天然生物质水凝胶吸附材料研究进展

生物质资源产量大,但是利用效率不高,将其制备成高吸附性水凝胶不仅可消除环境污染,减少资源浪费,还可以有效地降低成本。综述了近年来天然生物质功能性水凝胶的制备原料及其制备方法,重点概述了水凝胶在重金属离子和染料吸附方面的应用,总结并展望了生物质凝胶的重点研究方向和未来发展前景。     

Two milling time regimes in the evolution of magnetic anisotropy of mechanically alloyed soft magnetic powders

The milling time evolution of magnetic anisotropy of ball milled powders can be described considering two regimes. First, for short milling times, the main factor affecting the magnetic behavior of the alloy is the accumulation of internal stresses. Second, for long milling times, magnetic anisotropy can be explained using three contributions: long-range magnetoelastic, averaged short-range magnetoelastic and averaged magnetocrystalline anisotropies.     

诺基亚西门子软交换容灾方案的应用及改进

对诺基亚西门子软交换容灾方案和原理进行了深入研究和分析,并对方案进行了改进。对改进后的实际测试情况进行了总结,从而证明改进方案可以大大缩短倒换所需时长。保证了软交换出现紧急情况下业务能迅速的切换和恢复。     

Influence of Underlying Weak Soil on Passive Earth Pressure in Cohesionless Deposits

Finite-element simulations demonstrate the influence of underlying weak soil on mobilization of passive pressures in cohesionless deposits. Traditional passive earth pressure theories with typical angles of interface friction may overestimate passive forces in such cases. Simple analytical models that incorporate the underlying weak soil using traditional passive earth pressure concepts are shown to agree reasonably with the finite-element simulations. The studies presented herein are relevant for cases in which cohesionless soil deposits overlie soft clay, liquefiable sand, or other weak layers.     

基于IWOA-SVM的电路软故障诊断

针对DC-DC电路软故障诊断准确度不高的问题,提出了一种基于改进鲸鱼（IWOA）优化支持向量机(SVM)的电路软故障诊断方法。首先,对故障信号进行VMD提取特征向量;然后通过引用反馈机制来改善传统鲸鱼算法的全局搜索能力防止陷入局部最优,把线性因子改为非线性因子用来平衡全局搜索和局部开发能力来改进鲸鱼算法,以解决易陷入局部最优和局部开发能力低的问题。最后建立IWOA-SVM模型用来进行电路软故障诊断,最终对电路软故障诊断准确度不高的问题,实现了高效的诊断。根据故障诊断的结果表明,改进后的鲸鱼算法优化支持向量机相比本文对比的其他方法具有更好的诊断效果。故障识别准确率达到了99.1667%。     

Electrophoretic mobilities of dissolved polyelectrolyte charging agent and suspended non-colloidal titanium during electrophoretic deposition

Coarse (≤20 μm) titanium particles were deposited on low-carbon steel substrates by cathodic electrophoretic deposition (EPD) with ethanol as suspension medium and poly(diallyldimethylammonium chloride) (PDADMAC) as polymeric charging agent. Preliminary data on the electrophoretic mobilities and electrical conductivities on the suspensions of these soft particles as well as the solutions themselves as a function of PDADMAC level were used as the basis for the investigation of the EPD parameters in terms of the deposition yield as a function of five experimental parameters: (a) PDADMAC addition level, (b) solids loading, (c) deposition time, (d) applied voltage, and (e) electrode separation. These data were supported by particle sizing by laser diffraction and deposit surface morphology by scanning electron microscopy (SEM). The preceding data demonstrated that Ti particles of ∼1-12 μm size, electrosterically modified by the PDADMAC charging agent, acted effectively as colloidal particles during EPD. Owing to the non-colloidal nature of the particles and the stabilization of the Ti particles by electrosteric forces, the relevance of the zeta potential is questionable, so the more fundamental parameter of electrophoretic mobility was used. A key finding from the present work is the importance of assessing the electrophoretic mobilities of both the suspensions and solutions since the latter, which normally is overlooked, plays a critical role in the ability to interpret the results meaningfully. Further, algebraic uncoupling of these data plus determination of the deposit yield as a function of charging agent addition allow discrimination between the three main mechanistic stages of the electrokinetics of the process, which are: (1) surface saturation; (2) compression of the diffuse layer, growth of polymer-rich layer, and/or competition between the mobility of Ti and PDADMAC; and (3) little or no decrease in electrophoretic mobility of Ti, establishment of polymer-rich layer, and/or dominance of the mobility of the PDADMAC over that of Ti.     

Nanocrystalline Hf and Ta containing FeCo based alloys for high frequency applications

FeCo based nanocrystalline materials have excellent soft magnetic properties even at high temperature, but are limited to low frequency applications due to their relatively low electrical resistivities, ρ_e, resulting in high eddy current losses. Amorphous alloys of (Fe₈₁Co₁₉)₈₄M₉B₇ where M = (Hf, HfTa, Ta) were prepared by meltspinning and annealed for increasing times at their respective crystallization temperatures. The nanocrystalline alloys had coercivities less than 0.4 Oe and saturation inductions greater than 1 T. The electrical resistivities of the amorphous ribbons were all similar with values of ρ_e ? 180 μΩ cm. After annealing at the crystallization temperature, the M = Ta alloy had the largest ρ_e of 140 ± 3 μΩ cm. The Ta alloy also had the best high frequency properties, with an initial permeability of 822 at 1 MHz.     

MC-ORACLE: A tool for predicting Soft Error Rate

Natural radiation is known to be a source of microelectronics failure. For instance, neutrons, protons, heavy ions, and alpha particles have all been implicated in the occurrence of soft errors in memory devices. To predict the reliability of electronics devices we developed a tool called MC-ORACLE. This Monte Carlo application is based on the common empirical soft error criterion for a critical charge deposited in a parallelepiped sensitive volume. MC-ORACLE is able to deal with complex structures composed of various materials. It provides single and multiple error cross sections as well as the soft error rate.