基于Intel PXA255的便携式机械故障巡检仪中的触摸屏驱动的开发

提出了使用ADS7843芯片作为触摸屏的接口芯片,并给出了在基于Intel PXA255的Linux操作系统下触摸屏驱动程序中的中断处理程序流程和按键的坐标算法流程.     

电容触摸屏测试中的激励信号发生器的硬件电路设计

电容式触摸屏由于它具有响应时间短和透过率高等特点,近年来已成为一种主流的触摸屏,在智能终端和手机等产品中得到了广泛应用。首先给出了对电容触摸屏进行测试的硬件电路结构,它主要包含激励信号模块、控制模块、检测模块、探针模块、存储电路、LCD显示、键盘输入模块、接口模块等多个模块;其次,给出了激励信号模块的实现方法,采用DDS芯片AD9954来产生多种频率的信号波形。实验结果表明所给出的硬件电路结构可以产生所需要的多种类型的信号波形。因此,通过采用FPGA和DDS芯片来对激励信号发生器的硬件电路进行设计,能够较好地满足实际的对电容触摸屏测试的要求。     

基于STC单片机的触摸屏五点校准算法设计与实现

本文针对触摸屏在实际应用中的偏差,提出一种用于校准的五点算法。本系统采用高性能单片机作为主控单元,通过模数转换芯片ADS7845,采样触摸屏数据,经过校准传送到LCD显示器显示坐标。文中给出了数据采集终端软硬件的具体实现方案和五点校准的算法,并把它应用到实际生产中,有效地实现了触摸屏校准功能。     

基于ARM7TDMI内核的电子菜单系统的设计

与传统的以8位51单片机为核心的开发应用相比。ARM微处理器的性能和处理能力遥遥领先。其应用也日益广泛。从而获得了空前的发展。为克服传统点菜方式的弊端。本系统以S3C44BOX芯片作为微控制器。ADS7843作为触摸屏的控制器,设计了一种电子菜单．具有一定的市场应用价值。     

基于LPC2210＋μ Clinux的触摸屏设计

LPC2210作为一款以ARM7TDMI为内核的微处理器,正日益受到广泛的应用;μClinux作为一种运行于没有MMU的嵌入式微处理器的嵌入式操作系统,也广泛应用到嵌入式开发中。文章对LPC2210＋μClinux嵌入式系统中的触摸屏设计进行了探讨。触摸屏采用ADS7846控制器,给出LPC2210上触摸屏的实现,硬件设计原理及结构,并结合触摸屏硬件控制平台给出了μClinux触摸屏驱动程序设计的详细开发过程。     

触摸液晶显示器设计

提出一种具特定音效的触摸液晶显示器设计.利用TLV320AIC3254对音频信号做均衡处理,采用ADS7843和STC89C52设计串口控制器,采用gm5120和TM150XG-76N08实现硬件驱动设计.     

电阻式触膜屏在智能仪表中的应用

文中针对四线电阻式触摸屏在智能仪器仪表中的应用，介绍了四线电阻式触摸屏的结构原理与两种接口技术：与内置A／D的单片机接口；与专用A／D的接口。针对这两种接口技术，详细介绍了接口电路组成及原理，通过比较不同的读取控制方式选取了最适合触摸屏控制的中断方式，并且分析了触摸屏笔中断控制电路。同时在介绍与专用A／D的接口技术时，又简介了专用四线电阻式触摸转换A／D芯片ADS7843的特性、工作模式以及与8位AT89C2051单片机的接口电路。最后文章阐述了对脉冲干扰的保护措施。实际应用表明：电路稳定可靠，简单实用。     

基于STM32的数码相框和彩色画板设计

该设计具有三大核心模块:MCU、LCD、SD。以ARM coretex-M3为核心的STM32F103平台,2.8寸TFT_LCD触摸显示屏和8GB的SD卡为外接模块。通过触摸屏绘制彩色图片,将图片存储到SD卡中,从SD卡中获取图片,解码后输出到TFT_LCD上显示。实现不同类型的图片显示,如:BMP、JPG、JPEG。通过触摸屏驱动,BMP/JPEG图片的解码,FAT文件系统的解析,功能模块的切换,以实现幻灯片形式的播放。     

基于CAN总线的汽车信号记录仪的设计

介绍了一种基于CAN总线的汽车信号记录仪.采用构和功能设计方案.该系统主要由CAN模块、GPS模块、GPRS模块和LCD模块组成,分别介绍了各模块的硬件设计,并给出了嵌入式Linux环境下相关模块的驱动和应用程序的设计方法.该系统功能齐全,并具有很好的扩展性.     

一种电阻式触摸屏机械安装误差的校正方法

触摸屏是一种广泛应用于工业控制领域的人机交互与控制设备,电阻式触摸屏的误差校正是触摸屏精度的重要保证[1].本文研究了利用“三点法”对电阻式触摸屏的LCD屏和触摸传感模块的坐标误差进行校正,计算得到了坐标校正系数,方法消除了由于机械安装误差导致的触摸动作响应错误.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ...     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.     

CHARACTERISTCS OF FLUID FILM IN OPTIMIZED SPIRAL GROOVE MECHANICAL SEAL

In order to investigate the sealing performance variation resulted from the thermal deformation of the end faces, the equations to calculate the fluid film pressure distribution, the bearing force and the leakage rate are derived, for the fluid film both in parallel gap and in wedgy gap. The geometrical parameters of the sealing members are optimized by means of heat transfer analysis and complex method. The analysis results indicate that the shallow spiral grooves can generate hydrodynamic pressure while the rotating ring rotates and the bearing force of the fluid film in spiral groove end faces is much larger than that in the flat end faces. The deformation increases the bearing force of the fluid film in flat end faces, but it decreases the hydrodynamic pressure of the fluid film in spiral groove end faces. The gap dimensions which determine the characteristics of the fluid film is obtained by coupling analysis of the frictional heat and the thermal deformation in consideration of the equilibrium condition of the bearing force and the closing force. For different gap dimensions, the relationship between the closing force and the leakage rate is also investigated, based on which the leakage rate can be controlled by adjusting the closing force.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

OPTIMIZATION METHOD ON IMPELLER MERIDIONAL CONTOUR AND 3D BLADE

An optimization method for 3D blade and meridional contour of centrifugal or mixed-flow impeller based on the 3D viscous computational fluid dynamics (CFD) analysis is proposed. The blade is indirectly parameterized using the angular momentum and calculated by inverse design method. The design variables are separated into two categories: the meridional contour design variables and the blade design variables. Firstly, only the blade is optimized using genetic algorithm with the meridional contour remained constant. The artificial neural network (ANN) techniques with the training sample data schemed according to design of experiment theory are adopted to construct the response relation between the blade design variables and the impeller performance. Then, based on the ANN approximated relation between the meridional contour design variables and impeller performance, the meridional contour is optimized. Fewer design variables and less calculation effort is required in this method that may be widely used in the optimization of three-dimension impellers. An optimized impeller in a mixed-flow pump, where the head and the efficiency are enhanced by 12.9% and 4.5% respectively, confirms the validity of this newly proposed method.