无人驾驶飞机机载传感器数字化研究与应用

综述了几种不同型号的无人驾驶飞机机动数字式大气数据传感器测量系统的应用研究，着重介绍了一种小型数字式高度－空速测量系统的实现方法．该系统由小型硅压用传感器和微处理器组成，可以满足研制中的小型无人机机载数字式自动驾驶仪的要求．这种测量系统体积小、重量轻、性能价格比高，可望在其它低成本无人驾驶飞行器上得到广泛应用．     

声表面波(SAW)压力传感器输出频率的高精度测量方法研究

SAW压力传感器的输出量是频率,因之精确的频率测定是保证其可靠性和正确计量的关键之一.尽管目前有多种频率测量方法,但适合于和传感器相配套的用于生产现场的微型、高精度频率仪在国内尚罕见报道.我们在研究了现有频率测量方法的基础上,得到了一种适合于SAW压力传感器输出频率的测量方法,并给出了实现频率测量的原理和电路及其主要的电子元件.     

基于比例阀门的精密气压控制方法研究

对精密气压控制方法进行了研究,应用气动比例阀门作为压力产生的执行机构,采用模拟和数字PID双闭环反馈控制,采用硅压阻模拟传感器和数字石英谐振传感器的双传感器结构,对系统控制结构进行设计,实现了气体压力的精密控制,压力输出准确度为0.02％,控制稳定性达0．003％。系统压力产生速度快、没有压力过冲,控制精度高,稳定性好。该系统为压力参数的自动检定提供了精密压力基准源,可以实现压力表、压力变送器和压力传感器的自动检定校准。     

基于Internet的嵌入式Web声表面波压力传感器研究

SAW压力传感器是一种新型的高精度准数字化传感器,是目前国内外在高精度测量与信息化方面的一个研究热点,但在国内却少见报道.介绍了SAW压力传感器的工作原理及采用神经网络技术实现传感器智能化的方法,并详细地论述了基于LPC2104微处理器、uC/OS-II和LwIP TCP/IP协议实现嵌入式Web谐振式SAW压力传感器的技术.     

压力（位移）自动检测控制器检测单元接口设计

主要研究电液控制放大器模拟量输入通道中,位移传感器检测单元的测量放大电路和各输入信号与智能控制器的接口电路,使控制器的输入与各传感器的输出信息相匹配。     

数字式转速传感器的分类及评述

数字式转速传感器是电子计数式转速表中必不可少的组成部分。本文对当前国内外已得到应用的各种原理的数字式转速传感器进行综合评述,并通过系统的分类揭示出它们之间本质的联系,以便读者设计和选用时参考。     

Singular perturbation methods in the design of tracking systems incorprating inner-loop compensators and fast-sampling error-actuated controllers

Singular perturbation methods are used to exhibit the asymptotic structure of the transfer function matrices of discrete-time tracking systems incorporating linear multivariate plants which are amenable to fast-sampling error-actuated digital control only if extra plant output measurements are generated by the introduction of appropriate transducers and processed by inner-loop compensators. It is shown that these results greatly facilitate the determination of controller and transducer matrices which ensure that the closed-loop behaviour of such discrete-time tracking systems becomes increasingly non-interacting as the sampling frequency is increased. These general results are illustrated by designing a fast-sampling error-actuated digital controller for an aircraft.     

一种改善压力传感器曲线拟合特性的方法

压力传感器的输出特性受温度影响很大,把任意温度下传感器的特性都标定出来是不可能的,可以用数据拟合的方法在已测定温度特性曲线的基础上得到所需温度的压力传感器输出特性。本文提出一种采用分段拟合的方法对压力传感器数据进行拟合,通过在实际中的应用证明,这种方法可以显著提高拟合数据的精确性和简便性。     

基于V-F变换的硅压阻压力传感器的处理电路

针对硅压阻压力传感器提出了一种基于电桥本身参数的温度自补偿方法,并设计了一种差分输入、双参数输出的高精度处理电路用以获得电桥参数。该电路用简单元件搭建差分输入的电荷平衡式V/F转换器,根据不同组态的频率输出解算电桥参数。该电路巧妙地利用差分输入方式消除了共模电压引起的误差,巧妙借用参考电阻消除了基准频率的影响,最终的输出频率只与被测量和参考电阻有关。经实验验证,电桥电阻的测量精度能达到0.0068%,经补偿后的压力传感器精度可达0.039%,相比补偿之前提高了一个数量级。     

基于单片机的数字磁通门传感器

主要研究了一种数字磁通门传感器.这种传感器采用单片机的A/D对磁通门输出信号进行采样.采样后的数据通过串口送给计算机进行运算,并得到最终的输出量.该传感器对地球磁场进行了测量.结果显示:它的误差较小,改善了传统磁通门传感器的温度性能,提高了输出信号的稳定性.     

扩散硅数字化压力变送器补偿技术

详细介绍了扩散硅压力变送器的特点和现状,提出了对扩散硅压力变送器的数字补偿方案和补偿算法及实际测试结果。该技术提高了产品的整体性能,很好的解决了变送器零点温漂和灵敏度温漂的问题,并通过批量化的生产证实这种技术的正确性。     

压力传感器温度漂移补偿的一种新方法

提出了一种用于压力传感器的温度漂移补偿新方法。该压力传感器中包含了两个灵敏度不同的敏感电桥，它们被制作于同一芯片不同厚度的膜片上。所采用的一种电阻设置新形式，可有效节省芯片面积。通过双桥间的互补，同时消除了压力传感器的热零点漂移和热灵敏度漂移，文中给出了温度漂移补偿的具体算法及相应的实验结果。     

逻辑门混频器的特性分析与选择

在基于频率输出的传感器测量电路设计中,存在如何测量由测量参数引起的小频率增量问题,将被测信号和参考信号进行混频并进行滤波可以解决这个问题.将仅频率变化的两准数字信号施加于逻辑门进行混频,对混频器输出的特性进行了理论分析和实验验证,结果表明:异或门和同或门用作差频测量的混频器时,其输出效果明显好于其他基本逻辑门;当信号为...     

Synthesized and inherited functions

In this paper we introduce a new formal model for the concept of syntaxdirected semantics, calledmacro attributed tree transducer (for short: mat tree transducer). This model is based on (noncircular) attributed tree transducers and on macro tree transducers. In the first type of transducer, semantic values are computed by means of meaning names called synthesized attributes, and by means of context names called inherited attributes. Both, synthesized and inherited attributes represent basic semantic values. In the second type of transducer, semantic values are computed by meaning names only which are called states. However, in order to have a means of handling context information, states represent functions over semantic values. The new model integrates attributed tree transducers and macro tree transducers by allowing both, meaning names and context names to represent functions over semantic values. In analogy to the terminology of attributed tree transducers, we call such meaning names and context names also synthesized functions and inherited functions, respectively.We present an inductive characterization of the tree transformation computed by an mat tree transducer. We prove that mat tree transducers are more powerful than both, attributed tree transducers and macro tree transducers. We characterize mat tree transducers by the two-fold composition of attributed tree transducers. This characterization has three consequences: (1) the height of output trees of mat tree transducers is bounded exponentially in the size of the input tree, (2) the composition hierarchy of mat tree transducers is strict, and (3) mat tree transducers are closed under right-composition with top-down tree transducers, but not under left-composition. Moreover, we prove that the addition of inherited attributes does not increase the computational power of macro tree transducers.     

一种流量压力温度一体化传感器的设计

为了实现多参数综合测量,设计出一种小流量、压力、温度一体化传感器,该传感器主要由敏感元件和调理电路组成,信号输出采用0～5 V模拟输出.对传感器进行各项环境试验,试验结果表明:该传感器流量精度优于3％,压力精度优于0.2％,温度精度优于0.5％,流量热零点漂移小于0.2％ FS/℃,压力热零点漂移小于0.1％ FS/℃...     

Polysilicon strain-gauge transducers

Strain-gauge transducers with polysilicon resistors can be used successfully in various sensors. They have some advantages in comparison to monocrystalline silicon strain-gauge transducers. However, not enough information is available for the qualitative design of such transducers. The theoretical principles of the temperature dependence of the output signal for a constant supply voltage and constant supply current are described. A polysilicon strain-gauge transducer with a square diaphragm fabricated on the discussed principles is reported. It has an operating temperature range of −190- +300 °C, and weak temperature dependence of the output signal.     

A new contactless trackball design using Hall effect sensors

In this paper, a new trackball design based on a non-contacting motion detection mechanism is analyzed. It utilizes the hysteresis phenomenon of magnetic grade steel. In this design, the ball and a pair of electromagnets are made from magnetic grade stainless steel material. The electromagnets are placed outside and near to the ball surface. They record the magnetic information onto the ball surface. A Hall sensor, acting as a magnetic field detector, is placed inside each electromagnet. As the ball moves, the magnetic field recorded onto the ball surface produces instantaneous changes in the Hall sensor output. This output is then converted into a suitable format in order to determine the speed and direction of motion of the ball. Tests have been performed to check the viability of this technique. The promising test results have lead to the successful development of a prototype trackball.     

A statistical estimation method for segmentation of sonar range data

In this paper, we describe how to deal with an important sensorial activity that ultrasonic echo-locating systems for mobile robot navigation have often to perform, namely the extraction of straight line segments from range data and the accurate localization of the corresponding planar targets. It is commonplace that range data segmentation starts with using least squares interpolation algorithms for obtaining straight line segments: it is our goal to prove that caution must be called for in order to avoid somewhat misleading results. The case study concerns the use of a linear array formed by three ultrasonic transducers in a 2D specular environment composed of line and point acoustic targets.The segmentation algorithm we propose is subdivided into two functionally distinct modules, namely identification and localization. The identification module is based on a sequential hypothesis testing between alternative hypotheses that explain the sonar range data as originated from line or point targets. With regard to the localization module, we demonstrate that widely used approaches to sensor modeling are, to some extent, deceptively simple: the estimation accuracy for the localization of planar objects may be decreased by the inability of some traditional sonar sensor models to take properly into account the specularity of reflections. A physically based model of acoustic range sensors acting in specular environments allows us to design a localization module which is capable of producing accurate and unbiased estimates of the parameters of a planar geometric feature.The proposed theoretical framework is validated by the results of some experiments carried out with a spatial locating system consisting of a rotating linear array of three ultrasonic transducers.     

STM32平台的MPL3115A2气压传感器的应用

主要介绍Freescale的MPL3115A2气压传感器的性能、内部寄存器设置、工作模式配置等,给出基于STM32的MPL3115A2气压测量系统的应用实例。MPL3115A2内部集成了MEMS压力传感器和24位A/D转换器,可以实现压力(海拔)和温度的数字输出,测量精度可达30cm;I2 C总线接口设计可以方便地与MCU通信。     

Linking theorems for tree transducers

Linear extended multi bottom-up tree transducers are presented in the framework of synchronous grammars, in which the input and the output tree develop in parallel by rewriting linked nonterminals (or states). These links are typically transient and disappear once the linked nonterminals are rewritten. They are promoted to primary objects here, preserved in the semantics, and carefully studied. It is demonstrated that the links computed during the derivation of an input and output tree pair are hierarchically organized and that the distance between (input and output) link targets is bounded. Based on these properties, two linking theorems are developed that postulate the existence of certain natural links in each derivation for a given input and output tree pair. These linking theorems allow easy, high-level proofs that certain tree translations cannot be implemented by (compositions of) linear extended multi bottom-up tree transducers.