一种基于竞赛的两轮自平衡小车的设计

介绍一种两轮自平衡智能小车控制系统的实现方案。该系统以MC9S12XS128单片机作为主控芯片,采用一组激光传感器进行路径检测,使用ENC-03MA陀螺仪与MMA7361加速度计进行小车直立自平衡检测,利用BTS7960芯片进行电机驱动,使用增量式编码器进行速度检测,借助滑动电阻器和液晶屏对参数进行调整与观测。在软件方面,结合PWM技术和PID控制技术对小车的两个直流电机的转速进行控制,可以实现两轮小车的动态自平衡快速寻迹运行。实践表明该设计达到了理想效果。     

Comparison of two techniques for closed-loop drive of VR stepmotors without direct rotor position sensing

Closed-loop control of variable-reluctance (VR) step motors without using direct rotor-position sensing is investigated. Two nondirect rotor-position sensing techniques, namely the waveform detection (WD) and the pulse-width-modulation (PWM) techniques, were implemented and applied to a four-phase (15° step-angle) VR step motor. Test results show that a DC shunt motor and a DC series motor type of performance can be achieved from the step motor with PWM drive and WD drive, respectively. The stability problem encountered with the existing PWM controller due to motional EMF effects at higher operating speeds is investigated, and modifications are suggested to include speed as an additional control signal to make the system more stable. With the inclusion of the speed signal, the operating speed of the test motor is from 1000 to 1750 r/min. The performances for the two techniques are compared, and experimental results are presented     

A single-chip CMOS IC for closed-loop control of step motors

A CMOS integrated circuit for the closed-loop drive of step motors that avoids direct rotor position sensing is reported. The sequencer is integrated with the control circuit. The circuit has been fabricated on a 4 μm gate array, and its operation with the motor and chopper drive is characterized. Dynamic torque-speed characteristics, which are linear up to 85% of the maximum static torque with a 40% increase in power output compared to open-loop operation, have been obtained from a test motor. The CMOS integrated circuit controller makes the use of a step motor a viable alternative to series DC motors. It can be extended to provide a closed-loop drive circuit for step-mode operation     

Electric motor drives and control-past, present, and future

A comprehensive review of the state of the art in the field of electric motor drives and control strategies is presented. It is pointed out that drive technology has seen impressive growth during the last three decades. Recent advances in semiconductor power electronics and microelectronics have made is possible to use AC motors in many variable-speed drive applications. Implementation of new control techniques, such as field-oriented control and variable-structure control with sliding-mode features, has made AC motors a viable alternative to DC motors in high-performance drive applications. The advent of microprocessors/microcontrollers/microcomputers has made it possible to implement these complex control techniques     

A five-leg inverter for driving a traction motor and a compressor motor

This paper presents an integrated inverter for speed control of a traction motor and a compressor motor to reduce the compressor drive cost in electric vehicle/hybrid electric vehicle applications. The inverter comprises five phase-legs; three of which are for control of a three-phase traction motor and the remaining two for a two-phase compressor motor with three terminals. The common terminal of the two-phase motor is tied to the neutral point of the three-phase traction motor to eliminate the requirement of a third phase leg. Further component reduction is made possible by sharing the switching devices, dc bus filter capacitors, gate drive power supplies, and control circuit. Simulation and experimental results are included to verify that speed control of the two motors is independent from each other.     

机载光学定位测量跟踪器研究

研究提出了一种机载光学定位测量跟踪器,利用超声电机驱动的二维精密跟踪系统,驱动摄像机跟随待测对象做旋转运动,由无人机的位置和电机上编码器的数值,计算出待测对象的绝对位置。完成了以32位ARM处理器STM32F103ZET6为主控芯片的双超声电机驱动电路和超声电机驱动的二维精密跟踪云台的设计。实验结果表明,该系统响应时间小于3 ms,可高速高精度地实现水平和垂直方向0~360°旋转,当驱动信号频率为41 k Hz,编码器精度为2 000线时,电机位置精度在一个编码脉冲0.18°以内,最高速度可达150 r/min。     

Future vehicle driven by electricity and Control-research on four-wheel-motored "UOT electric march II"

The electric vehicle (EV) is the most exciting object to apply "advanced motion control" technique. As an EV is driven by electric motors, it has the following three remarkable advantages: 1) motor torque generation is fast and accurate; 2) motors can be installed in two or four wheels; and 3) motor torque can be known precisely. These advantages enable us to easily realize: 1) high performance antilock braking system and traction control system with minor feedback control at each wheel; 2) chassis motion control like direct yaw control; and 3) estimation of road surface condition. "UOT Electric March II" is our novel experimental EV with four in-wheel motors. This EV is made for intensive study of advanced motion control of an EV.     

无人机航空遥感平台机载作业控制系统设计

无人机相比较卫星和载人航空飞机遥感平台而言,具有成本低、灵活性高的特点。为了满足科学遥感实验、完成遥感作业任务、协调无人机电子吊舱中多组件工作、控制遥感影像传感器姿态,系统以AT89S52为主控芯片,扩展多路串口及USB接口以实现系统与外围设备的通信,同时设计了相机驱动模块及三自由度步进电机驱动模块。通过无人机航空遥感实验证明该系统能够满足遥感实验要求。     

Integration of VLSI circuits and mechanics for vibration control of flexible structures

The approach to modeling and control of smart flexible structures presented in this paper is based on the concept that an intelligent structure requires an internal knowledge of self to act intelligently. This knowledge can be acquired from local analog models of substructure dynamics and can be used in model-based controller designs. The key to this approach is the synergistic integration of analog VLSI circuit models and control with the sensing and actuation which are then to be embedded into the mechanical structure. This paper presents the motivation, development, and test results of analog VLSI circuit models for use in model-based control of smart flexible structures. Furthermore, control applications for these VLSI circuits are developed and simulation results are presented in which the VLSI circuits are used in adaptive vibration control of a simple mass-spring system.     

基于DSP的电动汽车双轮驱动系统设计

轮式驱动电动汽车采用多个轮毂电机独立驱动车辆-是未来电动车发展的一个重要的方向;开关磁阻电机不仅结构简单、运行可靠、制造成本低,而且调速范围宽、效率高-将其作为纯电动汽车驱动源具有优越性。本文以三相(16/12)极外转子开关型磁阻电机为基础,设计一种以TI公司生产的TMS320F28335 DSP控制芯片为核心的电动汽车双轮驱动系统。同时基于该控制系统,用实验法优化了前述开关磁阻电机的开通角和关断角,得出相电流与电磁转矩之间的关系,以实现通过分配双电机的相电流达到电机转矩的协调控制,从而实现电子差速的目的。     

Transmissionless Selectively Aligned Surface-Permanent-Magnet BLDC Motor in Hybrid Electric Vehicles

An axial-flux permanent-magnet brushless motor is designed with variable stator alignment of independent stators, thus allowing field weakening via a controllable and variable generated-voltage constant. This feature is particularly valuable in vehicle traction motors with large constant-power speed ratio, where there is also a strong desire to eliminate the need for gear changes and keep the overall size of the motor drive as small as possible. The advantage of high pole count as applied to this technique is discussed, and the simulation impact on motor drive kilovoltampere, efficiency, gradability, acceleration, and maximum speed over typical driving cycles is shown.      

四轮驱动四轮转向的汽车电子差速转向控制

通过汽车转向时稳定性分析阐明了四轮转向的优点。而鉴于轮毂电机在电动汽车上应用的诸多优点,及其功率受结构体积的限制,轮毂电机的应用将使汽车由性能更好的四轮驱动替代两轮驱动,它不但充分利用了地面对车轮的附着力和驱动力,而且结合用直线步进电机控制转向力的汽车转向系统,能更容易地实现全面改善转向性能的四轮转向系统。由于四轮驱动...     

Intelligent Mobile Video Surveillance System with Multilevel Distillation

This paper proposes a mobile video surveillance system consisting of intelligent video analysis and mobile communication networking. This multilevel distillation approach helps mobile users monitor tremendous surveillance videos on demand through video streaming over mobile communication networks. The intelligent video analysis includes moving object detection/tracking and key frame selection which can browse useful video clips. The communication networking services, comprising video transcoding, multimedia messaging, and mobile video streaming, transmit surveillance information into mobile appliances. Moving object detection is achieved by background subtraction and particle filter tracking. Key frame selection, which aims to deliver an alarm to a mobile client using multimedia messaging service accompanied with an extracted clear frame, is reached by devising a weighted importance criterion considering object clarity and face appearance. Besides, a spatial-domain cascaded transcoder is developed to convert the filtered image sequence of detected objects into the mobile video streaming format. Experimental results show that the system can successfully detect all events of moving objects for a complex surveillance scene, choose very appropriate key frames for users, and transcode the images with a high power signal-to-noise ratio (PSNR).     

Perception for collision avoidance and autonomous driving

The Navlab group at Carnegie Mellon University has a long history of development of automated vehicles and intelligent systems for driver assistance. The earlier work of the group concentrated on road following, cross-country driving, and obstacle detection. The new focus is on short-range sensing, to look all around the vehicle for safe driving. The current system uses video sensing, laser rangefinders, a novel light-stripe rangefinder, software to process each sensor individually, a map-based fusion system, and a probability based predictive model. The complete system has been demonstrated on the Navlab 11 vehicle for monitoring the environment of a vehicle driving through a cluttered urban environment, detecting and tracking fixed objects, moving objects, pedestrians, curbs, and roads.     

Control of switched reluctance motor torque for force controlapplications

The paper presents a method for controlling switched reluctance motor (SRM) torque for force control applications. SRMs are used in AdeptOne robots, and the authors perform experiments with two robots, controlled in coordination, in grasping and manipulation of various objects. The object and robot parameters are not exactly known, and adaptive methods are used to control the overall system. These methods are model-based control techniques which require high bandwidth torque control. This requirement is typical for high precision mechanisms. SRM characteristics are very nonlinear. In particular the torque ripple, friction, and the torque versus position and current relationships were analyzed in the context mentioned above, and specifically, for force control applications. The proposed method is based on a new commutation algorithm and a measured torque versus position and current relationship, used to smooth the SRM's torque ripple, hence generating a torque output nearly independent of position. Furthermore, the internal friction is estimated on-line, and compensated for. This renders a high accuracy torque tracking. The torque control method is based on feedback from the motor angular velocity, motor angle, armature current, and feedforward for friction compensation and cancellation of nonlinear effects. The method has been tested experimentally on Adept motors and the results were very encouraging. The method has been also used for adaptive control of two coordinated Adept robots     

基于LabVIEW的步进电机控制

为了实现PC机对步进电机的自动调节,设计了基于虚拟仪器技术的步进电机控制方案。系统采用L298N芯片进行驱动,以LabVIEW作为开发平台,并通过串口实现数据通信。结果显示,该系统能够很方便地实现步进电机的转速转向控制,而且利用虚拟仪器开发平台LabVIEW编写上位机程序,具有编程简单,控制界面友好,程序可移植性强的特点。     

车联网相关感知技术、产品以及案例分析

车辆感知技术是车联网的末梢神经,是车联网最关键的技术。车联网感知技术分为车况及控制系统感知和道路环境感知。介绍了车联网感知系列的电子产品,以及国内外车辆感知技术发展现状。最后介绍了车联网感知技术的应用案例,梅赛德斯—奔驰公司开发的循迹辅助系统。     

AET座架伺服控制系统的设计分析

分析了天线过顶跟踪出现"盲区"的原因及解决方法。介绍了极轨卫星遥感地面站天线跟踪伺服系统的系统组成、伺服控制系统设计。描述了天线控制单元、天线驱动单元、轴角编码单元和安全保护单元的组成。探讨了坐标转换和控制算法公式等。实际跟踪卫星的结果和仿真计算结果吻合,证实了该控制系统的正确性。     

基于AET座架的遥感跟踪伺服系统设计

在车载遥感站设备中,跟踪伺服控制系统是其重要组成部分。论文介绍了车载极轨卫星遥感站天线跟踪伺服系统的工作原理、系统构成等,给出了基于AET座架过顶跟踪伺服控制系统的控制策略及坐标转换公式。最后给出了系统实际跟踪卫星的跟踪结果。实际应用表明,该伺服控制系统方案设计合理．运行稳定,具有良好的动态跟踪性能。