Distributed control of LPV systems over arbitrary graphs with communication latency

This paper focuses on spatially distributed control systems where the controller sensing and actuation topology is inherited from that of the plant. Specifically, this paper considers distributed systems composed of discrete‐time linear parameter‐varying subsystems interconnected over general graph structures. These distributed systems are subject to a communication latency of one sampling period, where the information sent by a subsystem at the current time step is received by the target subsystem at the next time step. Analysis and synthesis conditions are derived for control design in this setting using a parameter‐dependent Lyapunov approach with the ?₂‐induced norm as the performance measure. Fast and easy‐to‐implement algorithms are also provided for constructing the controller in real time. The techniques developed are finally applied to a leader‐follower formation problem with intermittent communications.     

FVF‐Based Low‐Dropout Voltage Regulator with Fast Charging/Discharging Paths for Fast Line and Load Regulation

A new internally compensated low drop‐out voltage regulator based on the cascoded flipped voltage follower is presented in this paper. Adaptive biasing current and fast charging/discharging paths have been added to rapidly charge and discharge the parasitic capacitance of the pass transistor gate, thus improving the transient response. The proposed regulator was designed with standard 65‐nm CMOS technology. Measurements show load and line regulations of 433.80 μV/mA and 5.61 mV/V, respectively. Furthermore, the output voltage spikes are kept under 76 mV for 0.1 mA to 100 mA load variations and 0.9 V to 1.2 V line variations with rise and fall times of 1 μs. The total current consumption is 17.88 μA (for a 0.9 V supply voltage).     

Grounded capacitance multipliers based on active elements

In this study, we present two new grounded capacitance multiplier circuits based on a negative-type second-generation current conveyor (CCII-) and an inverting second-generation current conveyor (ICCII). The first proposed circuit consists of one CCII- and a voltage follower (VF) employing two NMOS transistors while the second proposed circuit is composed of an ICCII and an inverting voltage follower (IVF) including two NMOS transistors. Each circuit contains two resistors, and single grounded capacitor, which is attractive for integrated circuit realization. No active and passive component matching conditions are required for the realization of the proposed capacitance multiplier circuits. The simulation results are included to confirm the theory.     

广义非保守系统两类变量广义拟变分原理

为了进一步研究广义非保守系统的广义拟变分原理,同时考虑到阻尼力和伴生力的影响,首先明确了广义非保守弹性力学系统的基本方程,然后应用变积方法,建立了广义非保守弹性动力学系统的两类变量的广义拟变分原理,并应用两类变量的广义拟余能原理求解了一个广义非保守弹性结构系统具体算例,该方法较好地处理了动力分析中的一些复杂问题,顺利求得问题的解析解.     

Kinematical system of breadth cam profile design

The design solutions for breadth cam mechanism were presented. The main topics of the shape design for breadth cam was to calculate the coordinate at each contact point to determine the cam profile. The proposed method according to velocity and geometric relationships of instant velocity centers can easily determine each contact point at any instant moment. The cam profile was defined by contouring of the contact points. And also a program was developed by using Microsoft Visual C++ program, which can quickly and easily draw a 2D cam profile through the displacement diagram. Finally, the program was used to confirm the accuracy on the breadth cam profile design by computer animation graphically.     

红外焦平面阵列传感器中带隙基准源的设计

本文提出一种适用于红外焦平面阵列传感器的高精度BiCMOS电压基准和电流基准设计方案。该方案采用新型电压基准输出级降低Brokaw带隙基准源中的厄尔利效应使电流镜电流完全匹配,同时减小电压基准的输出阻抗;接着利用共源共栅结构的偏置电流提高带隙基准的电源抑制（Power Supply Rejection,PSR）特性;最后通过四个MOSFET管将基准电压和电阻电压钳制相等,进而得到一个高精度、低温度系数的电流基准;而以单个二极管连接的MOSFET作为电流基准启动电路的方式,可更进一步降低电路复杂性。系统采用CSMC 0.5um BiCMOS工艺,利用Cadence Spectre工具对电路进行仿真。结果表明,在电源电压5V,-40°C到125°C温度范围内,基准电压和基准电流的温度系数分别为13.11ppm/°C和31.18ppm/°C,输出电流波动低于0.5%,整体电路的PSR为-86.83dB,解决了恒定跨导基准源精度低的缺陷,符合红外焦平面阵列对基准源高精度、高PSR和低功耗的要求。     

一种基于矛盾思想方法的性能指标函数

由给定值阶跃响应过渡过程性能指标中存在的矛盾入手,分析了给定值跟随型控制系统优化的本质,认为其实质上是矛盾对立统一的产物,进而从抓住主要矛盾的观点出发,构造了一种以3个分立的过渡过程曲线特征参数为组成部分的性能指标函数.通过适当的均衡化和归一化变换处理,该性能指标函数在保持主要性能指标平衡性的基础上,加入了最大动态偏差限制、负向波动参数和过渡过程时间参考值,从而在保证稳定性的同时体现了控制要求和实际对象的动态特性,因而具有良好的适应性和针对性.仿真试验结果表明,使用该性能指标函数优化得到的系统具有给定动态偏差范围内快速的阶跃给定值跟随性能,同时具有良好的抗扰动性能和鲁棒性,适合于给定值跟随型控制系统的计算机仿真寻优.     

凹圆弧底直动从动件盘形凸轮机构设计新方法

本文找出了凹圆弧底直动从动件盘形凸轮与原有凸轮之间的区别与联系,并统一了原有凸轮的设计方法。新方法实 质上是内凸轮机构当滚子半径大于基圆半径时的一种特殊情况。     

建立凸轮廓线外凸性判据的一种新方法——支撑函数法

本文通过引人积分几何中＂支撑线＂和＂支撑函数＂的概念，揭示出其在平底从动件盘形凸轮机构中生动的几何直观背景，提出了一种简单通用、行之有效地建立凸轮廓线外凸性判据的新方法──支撑函数法。     

Beam stability on an elastic foundation subjected to distributed follower force

Problems related to the stability and behavior of a cantilevered beam with a tip mass on an elastic foundation and subjected to a distributed follower force are addressed. The stability of a beam partially attached to an elastic foundation is also considered. The dynamic stability of a beam subjected to a distributed follower force is formulated by using finite element method to get a general eigenvalue problem. The influence of the modulus on the elastic foundation and the ratio of the cantilevered beam’s mass to the tip mass on the critical flutter are investigated. Finally, the stability of the cantilevered beam is found to depend on both the modulus of the elastic foundation and the ratio of the cantilevered beam’s mass to the tip mass. This paper was recommended for publication in revised form by Associate Editor Hong Hee Yoo Dr. Jae-On Kim is now adjunct professor of Hanbat National University and president of Shinwall architectural & const. Co. Ltd. He has an excellent background in the architecural structure design and analysis. Dr. Kee-Seok Lee was educated at the Chungnam National University in Korea Ph.D. degree in mechanical engineering. For 10 years, he has a researcher in the field of mechanical design and control. Especially, he has an excellent background in the vibration control. At university, he has designend and established the control method for measuring Cam Profile without contact and air-bearing control method under disturbances. He is an author of 10 papers. Dr. Jin-Woo Lee was educated at the Kyushu institute of Technology in JapanPh.D. degree in of life-science and system engineering(Dec., 2006). He is a senior researcher at the steel solution research group of POSCO.