无线供能图像胶囊内窥镜的设计与实验分析

针对目前胶囊内窥镜受到能量限制的问题,设计了一种基于无线供能的微型化、低功耗的图像胶囊内窥镜。对无线供能电路,图像传感器电路,无线发射电路进行设计研究,搭建了无线能量传输系统平台,制作了无线供能图像胶囊内窥镜样机,并通过实验验证了无线能量传输系统发射线圈设计的合理性。通过与医院合作的猪大肠内部图像采集实验,验证了研制的图像胶囊系统样机的可行性。完整的图像胶囊内窥镜的尺寸仅为Φ10mm ×20mm ,图像传感器电路和无线发射电路的整体功耗最低约为65mW 。     

Cholesteric Liquid Crystal Polymeric Coatings for Colorful Artificial Muscles and Motile Humidity Sensor Skin Integrated with Magnetic Composites

Structural colorful cholesterics show impressive susceptibility to external stimulation, leading to applications in electro/mechano-chromic devices. However, out-of-plane actuation of structural colorful actuators based on cholesterics and the integration with other stimulation remains underdeveloped. Herein, colorful actuators and motile humidity sensors are developed using humidity-responsive cholesteric liquid crystal networks (CLCNs) and magnetic composites. The developed colorful actuator can exhibit synergistic out-of-plane shape morphing and color change in response to humidity, with CLCNs as colorful artificial muscles. Through the integration with magnetic control, the motile sensor can be navigated to open and confined spaces with the aid of friction to detect local relative humidity. The integration of multi-stimulation actuation of cholesteric magnetic actuators will expand the research frontier of structural colorful actuators and motile sensors for confined spaces.     

基于FPGA的YOLOv5s网络高效卷积加速器设计

为提升在资源受限情况下的嵌入式平台上卷积神经网络(Convolutional Neural Network, CNN)目标识别的资源利用率和能效,提出了一种适用于YOLOv5s目标识别网络的现场可编程门阵列(Field Programmable Gate Array, FPGA)共享计算单元的并行卷积加速结构,该结构通过共享3×3卷积和1×1卷积的计算单元提高了加速器硬件资源利用率。此外,还利用卷积层BN(Batch Normalization)层融合、模型量化、循环分块以及双缓冲等策略,提高系统计算效率并减少硬件资源开销。实验结果表明,加速器在200 MHz的工作频率下,实现的卷积计算峰值性能可达97.7 GOPS(Giga Operations per Second),其YOLOv5s网络的平均计算性可达78.34 GOPS,与其他FPGA加速器方案相比在DSP效率、能耗比以及整体性能等方面具有一定的提升。     

Design and Validation of a Power Supply Noise Reduction Technique

For the high-performance microprocessors with high-bandwidth I/O, the power supply noise needs to be controlled to ensure reliable high speed bus operation. This is generally done with high-quality package capacitors. These capacitors are generally lower equivalent series inductance (ESL) and lower equivalent series resistor (ESR). In this paper, we will present two implementations of an approach of using on-die resistors in series with the package capacitance to dampen the high-frequency noise. We will show by validation on the 90-nm technology that this technique is capable of reducing the noise by nearly 80% without adversely affecting the timings. The results of several validation experiments, including the measurement of noise and impedance of the I/O power delivery, and the post-layout simulation will also be presented.     

Stimulating Acrylic Elastomers by a Triboelectric Nanogenerator – Toward Self‐Powered Electronic Skin and Artificial Muscle

Dielectric elastomers are a type of actuator materials that exhibit excellent performance as artificial muscles, but a high driving voltage is required for their operation. By using the amazingly high output voltage generated from a triboelectric nanogenerator (TENG), a thin film dielectric elastomer actuator (DEA) can be directly driven by the contact‐separation motion of TENG, demonstrating a self‐powered actuation system. A TENG with a tribo surface area of 100 cm² can induce an expansion strain of 14.5% for the DEA samples (electrode diameter of 0.6 cm) when the system works stably within the contact‐separation velocity ranging from 0.1 to 10 cm s^?1. Finally, two simple prototypes of an intelligent switch and a self‐powered clamper based on the TENG and DEA are demonstrated. These results prove that the dielectric elastomer is an ideal material to work together with TENG and thereby the fabricated actuation system can potentially be applied to the field of electronic skin and soft robotics.     

三自由度气动教学机械手的研制与应用

针对目前在机电实验设备中缺少机、电、气一体的教学型实验设备的情况,介绍了一种基于气动元件开发的三自由度机械手。该机械手应用四个两种类型的气缸实现所有的动作,并留有底层的控制接口,使单片机（ARM、DSP）、PLC以及计算机可方便地对其进行控制。该机械手可以广泛应用在机械制图的测绘周、气动技术、单片机（ARM、DSP）原理与应用、PLC与电器控制、计算机控制技术等课程的实验以及机电综合实验周、机电产品创新设计等综合性实验中,应用效果理想。     

Validation of Design Techniques on a Quasi-Optics Test Bench

A two channel Quasi-Optics Network (QON) with a Frequency Selective Surface (FSS) to act as filter has been designed, constructed and tested in order to examine several aspects of the design, including the accuracy of the design software, the effectiveness of the FSS and the effect of moving components along the ray path in a QON. The QON was designed to feed an offset reflector system which required an input beamwidth of 20 degrees at ?8.68 dB. The two channels were the atmospheric sounding channels at 54 GHz (5 GHz bandwidth) and 89 GHz (3 GHz bandwidth). Gaussian beam techniques were used to design the QON with the final optimisation carried out using Physical Optics and Physical Theory of Diffraction. The measurements were carried using the facilities at National Physical Laboratory, London and Queen Mary, University of London. Agreement between predicted and measured performance was good, thus validating the design method, the equipment manufacture and the assumptions.     

Performance Evaluation of Relay Assisted Wireless Powered Network over Fluctuating Two Ray Fading Channel with Diversity Reception

Recently wireless powered networks have emerged as cutting-edge technology for addressing the power constraint issue of wireless devices (WD’s). This technology enables wireless nodes to harness power from the ambient radio frequency (RF) signal thus enhances the energy efficiency of the communication network and also improves the network longevity. The underlying principle of energy harvesting (EH) by wireless power transfer (WPT) has implications on system performance due to link distance and channel fading. To address the impact of channel fading on energy constraints WD’s this work explores the maximal ratio combining (MRC) diversity at the receiver node for the presented simultaneous wireless information and power transfer (SWIPT) model considering the energy constraint unmanned aerial vehicle (UAV) mounted amplify and forward (AF) relay. Assuming fluctuating two ray (FTR) fading scenario a novel analytical expression for the outage probability (OP) and symbol error rate (SER) for the presented system has been derived. As the FTR fading channel provides a generalized fading model and can significantly model millimeter wave band signals. Based on derived performance metrics this paper investigates the impact of variation on node positioning and EH time allocation factor on system outage probability (OP) and symbol error rate (SER) performance. Finally, the derived expression has been validated by comparing the results obtained from the Monte Carlo simulation.

     

一种新型的高速时钟数据恢复电路的设计和验证

针对高速(Gbit/s)串行数据通信应用,提出了一种混合结构的高速时钟数据恢复电路。该电路结构结合鉴频器和半速率二进制鉴相器,实现了频率锁定环路和相位恢复环路的同时工作。和传统的双环路结构相比,在功耗和面积可比拟的前提下,该结构系统的复杂度低、响应速度快。电路采用1.8 V,0.18μm CMOS工艺流片验证,测试结果显示在2 Gbit/s伪随机数序列输入情况下,电路能正确恢复出时钟和数据。芯片面积约0.5 mm~2,时钟数据恢复部分功耗为53.6 mW,输出驱动电路功耗约64.5 mW,恢复出的时钟抖动峰峰值为45 ps,均方根抖动为9.636 ps。     

卫星图像数据高速传输与处理系统的设计与验证

传统星上系统开发与研制通常是基于特定的专用宇航器件,这使得其开发周期长且可移植性较差。针对该问题,提出了一种基于Xilinx ZYNQ UltraScale+平台的ARM+可编程逻辑的解决方案。该方案用Vivado配置FPGA硬件架构,采用SDK(Software Development Kit)配置ARM实现两者数据交互。在整个系统设计中,通过集成在芯片内部的高速串行收发器和Aurora协议作为载体进行高速片间传输;采用自定义帧协议保证传输可靠性及安全性;采用AXI-Stream接口使其具有各类算法即插即用的灵活性;最后为验证本系统可以支持各类算法进行星上实时图像处理,通过在逻辑侧添加 Sobel 边缘检测算法进行验证。测试结果表明该系统图像数据传输无误码,星上串行高速传输速率较高,系统总体传输延时较低,且系统具有较强的算法通用性。     

双闹钟数字时钟芯片设计

简述了一种双闹钟数字时钟芯片的设计分析，具体介绍了其中三态输入电路、可逆计数器、输出解码／驱动器等电路的设计。这种数字时钟芯片用途广泛，外围电路简单，并可以选择利用电网的50／60Hz作为烦率基准和电源，适用于数字钟、钟控收音机产品的应用。     

PCB数控钻孔机的气路系统设计与研究

介绍了空气质量对PCB数控钻孔机的重要性,运用气路图从原理上重点分析PCB数控钻孔机的气路设计的要点,并对其中的关键元器件气浮主轴和气缸气路设计进行详细分析、计算和测试,通过在PCB数控钻孔机上实际应用,该系统可满足PCB数控钻孔机应用需求。     

一种实用的数字式气动点焊机控制器的设计

本论文介绍了一种实用的数字式气动点焊机控制器的设计。控制器结构简单、使用方便。由单片机来控制焊接各个工序及完成用户的设定，达到精确点焊的目的。     

高精度PCB数控钻孔机定位精度的设计与研究

介绍了PCB数控钻孔机的全闭环控制系统原理,实验分析光栅尺分辨率对PCB数控钻孔机的定位精度的影响,通过一定程度上提高光栅尺分辨率,在PCB数控钻孔机上实际应用,可以满足目前BGA钻孔对精度的要求。     

L波段EDFA的优化设计和实验验证

基于Giles模型,对L波段掺Er光纤放大器(EDFA)的特性进行了数值模拟,分析了采用高掺杂Er纤放大器输出性能的改善。根据数值分析的结果进行了优化设计,使用9m长的高掺杂Er光纤进行了实验研究。实验结果表明．在泵浦功率为100mw时,小信号增益在10dB以上,噪声指数小于6dB。     

硅微机械二维倾角传感器结构设计

提出了一种结构简单,制造工艺容易实现的硅微机械二维倾角传感器结构设计,它由蝶形质量块和连接它们的四个成十字形的硅应变梁以及具有过载限位保护功能的硼硅玻璃衬底构成.传感器能同时检测出绕两轴的倾角变化.分析了硅应变梁的受力情况,得到了与倾角的解析关系,并用有限元方法验证了结果,理论灵敏度为0.75 mV/ °.     

一种伪差分两级环形振荡器的设计

设计了一种伪差分两级环形振荡器,可为锁相环提供8 GHz四相位正交时钟。通过分析耦合两级环形振荡线性模型,对四级环形振荡结构进行优化,提出了伪差分两级环形振荡结构。基于单级缓冲器的开环分析,可对振荡器的输出频率进行精准估算,并判断振荡情况。采用65 nm CMOS工艺进行设计与仿真。结果表明,在1.2 V电压下,振荡器的功耗为6.9 mW,1 MHz频率处的相位噪声为－82.104 5 dB,满足高速SerDes接口的设计要求。     

人工传输线传输特性的分析与设计

人工传输线以其慢波效应可以使微波部件小型化,因而得到了广泛应用。首先介绍了人工传输线的基本原理,给出了一种简洁的等效电路模型,然后推导出了基于该模型的传输特性计算公式;在此基础上,根据仿真结果推算出各等效电路参数,从而得到了人工传输线传输特性与等效电路参数的关系;最后设计制作了人工传输线,测试结果与分析结果比较吻合,证明了提出的分析模型是有效的。为进一步简化设计平面型人工传输线奠定了基础。     

一种超宽带双信道速调管输出回路的设计和实验

该文介绍了一种超宽带双信道速调管输出回路的设计思路和实现过程。以Ansoft HFSS软件为设计平台,在S波段设计出一个带宽超过550 MHz的超宽带双信道双间隙耦合腔输出回路。设计了信道转换机构,并分别确定了两个信道的谐振腔参数。得出了不改变两个谐振腔参数,只需调节耦合槽的尺寸就能够实现信道转换的结论。通过对HFSS软件建立的模型进行计算,得到了双间隙耦合腔输出回路中各模式的频率,与冷测结果基本一致。利用集中元件等效电路法计算了双间隙耦合腔输出回路的间隙阻抗,计算结果与冷测结果基本一致。     

微机械气动红外探测器的计算机仿真

介绍了一种可工作于室温环境下的微型气动式红外探测器，它基于气体介质吸收特定波段的红外辐射后以无辐射气动方式激励并产生一系列热效应的物理基础，可获得包含红外辐射源信息的信号。建立了符合器件工作模式的有限元模型，采用流体-热-结构耦合方法分析了器件的机械行为以及气体介质的温度场分布，模拟并讨论了不同结构参数对器件性能的影响，为采用MEMS技术研制具有波长选择特性的非致冷气动式红外探测器提供了理论基础。