Simple physical model for chemomechanics

We present a simple model linking chemical interactions with macroscopic mechanical deformations for polymer‐coated microcantilever devices. The chemo‐mechanical process is treated in terms of Fickian diffusion followed by a structural relaxation of the polymer‐guest complex. The model is tested on a series of microcantilever bending experiments, in the presence of different isotopologues, and at different incident guest fluxes. In many cases, a nontrivial behavior, expressed by the appearance of an overshoot, is observed. The new model provides insight into the ways chemical interactions and reorganization processes manifest themselves in mechanical processes. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys., 2013     

对地观测卫星过顶预报与定轨模型的建立

针对某些对地观测卫星,其轨道参数不公开,只能通过对卫星的运行规律建立数学模型,推导出卫星的过顶时间,从而使对地目标有效规避卫星的对地观测.首先从卫星运行的基本规律出发,根据稀疏数据进行定轨建立了卫星定轨的数学模型,利用牛顿迭代法递推出轨道根数,同时利用摄动补偿优化了模型,再通过八阶龙格库塔法,进行轨道递推,得到了卫星过顶时间与轨道信息的对应关系.     

具有输入饱和因子的滞后关联大系统的分散控制

研究了一类具有饱和因子的滞后关联大系统的分散控制问题.首先对饱和因子进行了巧妙地处理,再通过构造Lyapunov泛函,利用(LMI)方法给出了分散控制状态反馈控制器的设计方法.控制器通过解线性矩阵不等式即可得到,计算简便.最后,数值例子和仿真说明了该设计方法的有效性.     

集成结构振动主动控制和抑制

采用一种新的压电板单元,建立了含有分布压电传感元件和执行元件的集成结构的有限元动力模型。研究了这种集成结构在常增益负速度反馈控制规律作用下,振动的主动控制与抑制的问题,并提出了集成结构振动主动控制和抑制的一般方法。最后,提供了数值示例,说明本文提出方法的有效性。     

Design of novel morphing structures based on bistable composites with piezoceramic actuators

Instead of attempts to avoid the large out-of-plane deformations of multilayered fiber-reinforced composites caused by residual stresses, these deformations can be advantageously used for technical applications such as novel morphing structures, where only a discontinuous energy impulse of an actuator is necessary to change the configuration of the structure. For the design of such innovative morphing structures with piezoelectric actuators, novel nonlinear semi-analytical and numerical simulation models have been developed and verified experimentally. Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 42, No. 4, pp. 475–494, July–August, 2006.     

Field‐induced bending deformation of various rubber films

The field‐induced bending deformation of various rubber films was measured. The deformation tended to increase with the increase in the conductivity of the films. In addition, the effect of doping with tetracyanoethylene (TCNE) was also studied. This doping significantly enhanced the bending deformation and conductivity when the film was made of acrylonitrile‐butadiene rubber. The tip of the film (5 × 30 mm², 0.28 mm thick) moved by 3 mm due to the bending deformation induced by the applied voltage (140 V). Such a rubber film may find applications as a polymer actuator. Copyright © 2007 John Wiley & Sons, Ltd.     

Electromagnetic Activation of Shape Memory Polymer Networks Containing Magnetic Nanoparticles

Summary: By incorporation of surface‐modified superparamagnetic nanoparticles into shape memory polymer matrices, remote actuation of complex shape transitions by electromagnetic fields is possible. The composite thermosets of oligo(ε‐caprolactone)dimethacrylate/butyl acrylate contain between 2 and 12 wt.‐% magnetite nanoparticles serving as nanoantennas for magnetic heating. It is shown that the particles are dispersed homogenously within the matrix and that the basic thermal and mechanical properties of the polymer matrix are maintained. The specific loss power of the particles is determined to be 30 W · g⁻¹ at 300 kHz and 5.0 W. During the shape transition at 43 °C, no further temperature increase is observed.