外文翻译---电梯定位控制系统模型的设计.docx

附录1 文献翻译A Design of Elevator Positioning Control System ModelZhang Yajun, Chen Long, Fan LingyanSchool of Electronics & Information，Hangzhou Dianzi UniversityHangzhou, Zhejiang, 310018The Peoples Republic of CABSTRCTThis paper presents a design of elevator positioning control system model based on the ATmega128 microcontroller. The model mainly includes MCU control module, stepper motor drive module, infrared detection module, LCD display module and keys module. The elevators running path is set by keys; the elevators running location is detected by the infrared binate tubes. Stepper motor is the executive component. MCU controls the speed and direction of the stepper motor by inputting pulse signals to its drive chip L298. LCD displays the real-time information of elevators running status. Key Words: ATmega128 microcontroller, stepper motor, drive chip L298, infrared detection circuit.1. INTRODUCTIONA four-floor elevator system module is designed in this paper. The object of elevator system module is shown in figure 1. The size of the model and the distance between the layers are shown in the figure. The system model provides an intuitional and thorough description for the construction and action principle of elevator, and gives a platform for the further research of the new elevator control technologies. It has a certain reference in relevant professional experiments teaching. It can be chosen as a teaching model for university teachers when they instruct stepper motors drive and control. In addition, the model has a certain value for research and development of high-rise elevator control software.2. SYSTEM STRUCTURE AND WORKING PRINCIPLEThe basic structure diagram of the elevator positioning control system model is shown in Figure 2. The model includes MCU control module, stepper motor drive module, infrared detection module, LCD module and keys module. The elevators running path is set up by keys; the real-time information of the elevators location is detected by infrared detection circuits and is fed back to the MCU. The speed and direction of the stepper motor are controlled by MCU inputting timing pulse signals to its drive chip L298(internal circuits are H-bridge drive circuits).The elevator stops when the information input by the key and the feedback signals of the infrared detection circuits are the same and the elevators real-time running status is displayed by the LCD1602.3. SYSTEM HARDWARE DESIGN3.1 Stepper motor drive module designStepper motor drive circuit is shown in Figure 3. L298 integrated chips input ports connect with the system MCU I/O ports and its output ports connect with the signal input ports of two-phase four wires stepper motor. MCU I/O ports output certain timing pulse signals to drive chip to control its outputs, which makes the stepper motor rotate positively or reversely. Stepper motor rotational speed is directly proportional to the frequency of input pulse, which means the higher frequency of the input pulse, the faster stepper motor rotate speed, and vice versa. The internal circuits of L298 chip are H-bridge driver circuits, as shown in Figure 4. VD1, VD2, VD3, VD4 are continued flow diodes for protecting the drive circuit. When Q1, Q4 binate tubes in the H-bridge circuit turn from on to off, the current cant change immediately and flows as original direction, VD2, VD3 provide loop circuit at this time. When Q1, Q4 disconnect the current forms a continued flow loop as follows: GND VD3 stepper motor VD2 VCC. Similarly, VD1, VD4 provide flow loop when Q2, Q3 turn from on to off, the current forms a continued flow loop as follows: GND VD4 stepper motor VD1 VCC. D1 and D6, D2 and D5, D3 and D8, D4 and D7 are quadruplet binate tubes of continued flow in the drive circuit.3.2 Infrared detection module designThe infrared detection circuit is composed of infrared emitting and receiving tubes and comparator as shown in figure 5. The infrared emitting tubes are installed at the point of O, A, B, C. The infrared receiving tubes are installed at the point of O, A, B, C. When the infrared receiving tube receives infrared signals, its resistance is quite small; the voltage at point A is about 4V. When the infrared receiving tube doesnt receive infrared signals, its resistance is very large, at this time the voltage at A point is about 0.8V.The voltage of point B is the reference voltage which is about 1.5V(realized by adjusting 10K potentiometer) and the comparator output port connect with 10K pull-up resistor. When the voltage at point A is higher than point B, LM339 outputs high-level signal to MCU I/O port. Otherwise, LM339 outputs low-level signal to MCU I/O port. MCU achieves the exact location of the elevator through detecting high or low level signal output by comparator and the key input signal in the system module.3.3 MCU control module and key module designFigure 6 MCU control module and keys module circuits MCU control module and keys module circuit is shown in Figure 6. Keys are defined as follows: key P1.3 is a start key and the elevator start to rotate when key P1.3 is pressed. When the elevator is rotating, it will enter to state of emergency (elevator stops at last point along the moving direction) if we press key P1.3. P1.4, P1.5, P1.6, P1.7 are keys for O floor, A floor, B floor, C floor individually. Key P3.0 is a shift key and the modification item starts flashing and the flashing information can be amended when key P3.1 is pressed. Key P3.2 is the enter key. The modification item stops flashing, amendments is over and the elevator runs according to the revised information when key P3.2 is pressed. We can make more flexible definition of the keys during the course of designing the system software in order to achieve more functions.3.4 Display module designLCD1602 display module are adopted and used to display model running status. The information displayed mainly includes the elevators current location, operation order, operation time, running status (UP, DOWN, STOP) and so on.4. SYSTEM SOFTWARE DESIGNThe basic idea of the program design is as follows: Firstly, the operation of pressing keys can set the running path of the elevator model. Secondly, infrared binate tubes carry out the real-time detection of the elevators location after the elevator starts. Thirdly, MCU scans the infrared circuit I/O ports real-time detection results. The detection result is low-level when the elevator reaches the target floor. Meanwhile, the elevator stops and the array of indicators move back a bit. The elevator will restart if the comparison result of the current and the next floor (position of the array indicator) are not consistent. The process repeats until the array bits pointed by array indicator become zero, and then the elevator stops. In addition, the elevator should increase speed slowly after it starts and reduce speed gradually before it stops in order to smooth the operation of the elevator and avoid vibration or swing. To achieve this goal in the program design, we can control the drive circuits pulse signal frequency given by MCU. The elevators rotation speed is directly proportional to the pulse signal frequency, which means the higher the pulse signal frequency, the quicker the elevator rotation speed, and vice versa. In the process of the elevator running from zero to maximum speed, the MCU output higher and higher pulse signal frequency to the drive circuit to realize the elevators acceleration. Similarly, the MCU input lower and lower pulse signal frequency to the drive circuit to realize the elevators deceleration.5. CONCLUSIONWe choose ATmega128 microcontroller as the core control component and stepper motor as the implementation component, use L298 integrated chip to drive stepper motor and infrared binate tubes to detect the location of the elevator and acquire real-time information to achieve a position control system model for teaching. This model has the characteristics are as follows: (1) The operation order of elevator can be preset and the real-time information of the elevators running order and running time can be displayed by LCD. The running order and running time can be modified by pressing certain keys. The system can enter into the emergency situation by pressing certain keys. The elevator is smooth and uniform during the course of acceleration and deceleration.(2)Integrated L298 driver chip which used in the motor driver circuit is simple, high integrated, convenient to control.(3)The design of infrared binate tubes detection circuit makes elevator accurate positioning. Information displayed by LCD is rich and the display interface is user-friendly. The experiment shows that the system model has the characteristics of stability and high reliability. It can be used in teaching relevant professional course and designing practical elevator control software.6. REFERENCES1CHEN Ji-Wen, FAN Wen-Li, LI Yan-Feng, YU Fu-Sheng,“ Research on the Elevator Control Simulation System, ”Development & Innovation of Machinery & Electrical Products,pp.96-100, Jan, 2008, 21(1).2CAO Ai-guo, MAO Mei-jiao, “The Research of the PLCbased Five-floor Elevator Model Monitor System,” Modern Machinery, pp.86-87, 2007(2).3Qiu Yaner, “Application of PLC in Elevator Teaching Model,” Mechanical Management and Development, pp.53-54, Dec.2007(6),4LI Zhong-hua, TAN Hong-zhou, ZHANG Yunong, “Research on Fast Simulation of Elevator System for Complex Building,” Journal of System Simulation, pp.4561- 4569, Oct.2007, 19(19).5ZHANG Xian-miao, LIU Xin-wei, JIN Tian-jun, LV Zhengyu, “High reliable communication system of the elevator,” Mechanical & Electrical Engineering Magazine, pp.4-6, Oct. 2007, 24(10).6SUN Yaning, “ Design and Implementation of Elevator Model,” Low Voltage Apparatus, pp.12-15,2007(16).7ZHAO Yong-mei, YU Bing, FENG Fei, “ Elevator Model Control System Based on S7-200,” Jiangsu Machine Building & Automation, pp.93-95, Dec 2004.8 Sun Houhuan, Bai Chongzhe, “The Elevator Control System Based on the Pulse Count of PLC,” Electric Drive, pp.36-39, 2003(1).电梯定位控制系统模型的设计摘 要本文提出了一种基于ATmega128单片机的电梯定位控制系统模型的设计方法。该模型主要包括单片机控制模块，步进电机驱动模块，红外检测模块，液晶显示器显示模块和按键模块。电梯的运行路径是由按键确定的，电梯的运行位置是由红外三极管检测到的，步进电机是执行元件。单片机通过输出脉冲信号到驱动器芯片L298来控制步进电机的速度和方向。液晶显示器显示电梯运行状态的实时信息。关键词：ATmega128单片机，步进电机， 驱动器芯片L298，红外检测电路。1 引言本文设计了四层电梯系统模块。电梯系统模块的示意图如图1所示。模型每层之间的距离如图中数字所示。系统模型为电梯的结构以及运行原理提供了一个直观和全面的描述，并为进一步研究新的电梯控制技术提供平台。在专业实验教学方面它具有一定的参考价值。当大学教师教授步进电机的驱动和控制时，它可以作为一个教学模型。此外，该模型对研究与发展高层电梯控制软件也具有一定的价值。2 系统结构及工作原理电梯定位控制系统模型基本结构框图如图2所示。该模型包括单片机控制模块，步进电机驱动模块，红外探测模块，液晶显示模块和按键模块。电梯的运行路径是由设立键确定的，电梯位置的实时信息是由红外探测电路把信息反馈到微控制器检测的。步进电机的速度和方向是由单片机输出脉冲信号到驱动器芯片L298（内部电路的H桥驱动电路）来进行控制的。当由按键输入停止信息时，电梯停运，此时，由红外探测电路测得的当前位置的反馈信号就是电梯的实时运行状态，此状态将通过LCD1602显示出来。3 系统硬件设计3.1 步进电机驾驶模块设计步进电机驱动电路如图3所示。L298 集成芯片的输入端口连接系统微控制器I/O端口，输出端口连接两相四线步进电机的信号输入端口。单片机I/O端口输出一定的脉冲信号到驱动器芯片以控制其输出，从而使步进电机正向或反向旋转。步进电机转速与输入脉冲频率成正比，这意味着脉冲的输入频率越高，步进电机的旋转速度越快，反之亦然。L298芯片的内部电路是H桥式驱动器电路，如图4所示。VD1 ，VD2 ，VD3 ，VD4是用以保护驱动电路的续流二极管。当Q1，Q4三极管H桥电路由开变为关闭，电流不能迅速改变， 继续按原始方向流动，VD2 ，VD3此时提供回路电流。当Q1，Q4断开，形成续流回路如下：接地VD3步进电机VD2虚拟通道连接。同样，当Q2，Q3由开变为关闭，VD1，VD4提供回路电流，续流回路如下：接地VD4步进电机VD1虚拟通道连接。D1和D6 ，D2和D5， D3和D8 ，D4和D7是续流驱动电路中的二极管。3.2 红外检测模块设计红外检测电路由红外发射与接收管组成，如图5所示。红外发光管安装在O，A，B，C点。红外接收管安装在O，A，B，C点。当红外接收管接收红外线信号，其电阻相当小，在A点电压约为4V的。当红