两栖机器人轮桨腿驱动机构多目标优化设计

提出了一种既能够在陆地上爬行,又能够在一定深度的水下浮游和在海底爬行的新概念轮桨腿一体化两栖机器人;多运动模式和复合移动机构是该机器人的突出特点.分析了轮桨腿复合式驱动机构的运动机理,并采用多目标优化设计理论和算法,对驱动机构的爬行性能和浮游特性进行了综合优化,得到了两栖机器人驱动机构的结构优化参数.虚拟样机的仿真结果证明了该轮桨腿一体化两栖机器人驱动机构的综合运动性能良好,对非结构环境具有一定的适应能力。

Performance analysis of very-small-aperture lasers

The fabrication of very-small-aperture lasers is demonstrated, and their performance is analyzed. Because of strong optical feedback caused by a gold film on the front facet of the laser, its behavior changes: The threshold current decreases, the density of light inside the laser diode and the redshift effect of the spectra are enhanced, and the laser diode's lifetime is shorter than that of common laser diodes with large driving current. (c) 2005 Optical Society of America

Improved performance in organic light emitting diodes with a mixed electron donor-acceptor film involved in hole injection

Organic light emitting diodes using a mixed layer of electron acceptor 3, 4, 9, 10 perylenetetracarboxylic dianhydride and electron donor copper phthalocyanine (PTCDA:CuPc) on indium tin oxide (ITO) anodes were fabricated. The device properties were found to be strongly dependent on the thickness of the PTCDA:CuPc film: both the power efficiency and the driving voltage of the device were optimized with a thickness of PTCDA:CuPc ranging from 10 to 20 nm. As compared to the conventional ITO/CuPc hole injection structure, the ITO/PTCDA:CuPc hole injection structure could remarkably enhance both the luminance and the power efficiencies of devices. A mechanism of static-induced, very efficient hole-electron pairs generation in mixed PTCDA:CuPc films was proposed to explain the experimental phenomena. The structural and optical properties of PTCDA:CuPc film were examined as well. (c) 2007 American Institute of Physics.