Design of automatic door control system based on EDA technology (FPGA)

introduction

Doors and human civilization are twins, and they have been developing along with the development of human civilization. Today in the 21st century, doors have highlighted the concept of safety and effectiveness: effective prevention, passage, and evacuation. At the same time, they have also highlighted the concept of architectural art, emphasizing the overall coordination and harmony between doors, buildings, and the surrounding environment.

Large-scale specialized door production began 150 years ago. In the process of continuous development and improvement, a large number of large-scale professional manufacturers have emerged. The advanced form of doors - automatic doors originated in Europe and the United States. Today, they have developed rapidly and have formed a family of automatic doors with complete types, perfect functions and fine workmanship.

China began to introduce European automatic doors more than ten years ago and applied them in large and medium-sized public places such as hotels, airports, shopping centers, banks, office buildings, etc., adding bright and fashionable colors to these buildings. Theoretically, automatic doors should be an extension of the concept of door use, which is the improvement and improvement of door functions according to people's needs. Therefore, the understanding of automatic doors should start from people's requirements for door functions. As a part of the building, the door, in the most basic sense, must meet the two requirements of isolating the external environment and not hindering people's passage. Therefore, the door body itself should be firm and sealed.

Therefore, there is a certain market for designing an automatic door control system that is easy to operate, stable and reliable in operation, and low in cost.

In order to achieve the above purpose, the automatic door control system designed in this paper adopts the following design scheme: it adopts three driving modes: button, wireless remote control, and infrared sensing, which can be controlled automatically or manually, with simple operation and wide application range; it adopts EDA technology to design the state conversion of the main controller, and can diagnose errors with software; it adopts automatic reset and motor-specific control chips to ensure the reliable operation of the system. Since the design adopts VHDL design of EDA technology instead of traditional single-chip microcomputer design, it is a top-down design method, which shortens the development cycle of the system and reduces costs. The design of each part of the system will be introduced in detail below.

1 System Analysis

This system realizes the opening, closing and stopping of the automatic door through three driving modes: buttons, wireless remote control and infrared sensing, and the button has the highest priority. The infrared sensing switch automatically opens the door when someone comes. You can also use buttons and remote controls to control the opening, closing and stopping of the automatic door through manual control. The wireless remote control can be selected in the market according to actual conditions. The main controller circuit of the automatic door uses an FPGA chip to complete the conversion control of the door operation state according to the driving signal, position and external signals of encountering obstacles; the motor control circuit of the automatic door controls the opening, closing and stopping of the motor according to the forward and reverse and stop control signals issued by the main controller, and realizes the speed regulation of the forward and reverse operation of the automatic door.

2 Motor Control Circuit Design

In order to ensure the motor control is simple and reliable, the design uses the motor-specific control chip MC33033 as shown in Figure 1. This chip can perform open-loop and closed-loop control of the DC motor speed, and can also adjust the motor speed for forward and reverse rotation. MC33033 is a typical chip of the second-generation brushless DC motor controller. The chip contains a rotor position decoder and can provide a reference voltage with temperature compensation for the sensor. Another feature of MC33033 is that it contains three open-collector top drivers and three high-current push-pull bottom drivers designed for MOSFET drive power, and has motor overcurrent detection and protection functions.

When MC33033 is applied to the motor control of automatic doors, the stop, forward and reverse signals obtained by the logic operation circuit are used as three input signals (the priority order is stop, forward and reverse. Under normal circumstances, only one of the three signals is valid). The forward and reverse signals are connected to the 3rd terminal of MC33033 through the logic gate. If the terminal is high, MC33033 will make AT output high, and the CB terminal outputs PWM modulation waveform, and control the switch action accordingly, so as to realize the forward rotation of the motor and adjust the speed; conversely, MC33033 will make AB output high, and the CT terminal outputs PWM modulation waveform, and control the switch action accordingly, so as to realize the reverse rotation of the motor and adjust the speed. When the level is low, the stop signal is connected to the 19th terminal (enable terminal) of MC33033. If it is high, the chip will stop working normally, and the motor can be stopped at this time. This is the principle of how the motor part realizes the forward rotation, reverse rotation, stop and forward and reverse speed regulation of the motor.

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3. Automatic door main control circuit based on FPGA

The advantage of using VHDL for electronic system design is that it is a top-down design method. Designers do not need to consider the actual process and can focus on the design ideas, which is more conducive to the simplicity and practical application of the system.

3.1 Design Idea

First, draw the state diagram of the automatic door controller. Analysis of the operation process of the automatic door shows that: the door is in a closed state at the beginning, and it opens when there is an opening signal. If there is resistance during the opening and closing process, it will pause for a while, and then automatically continue the original opening and closing action. During the operation, the door will stop when it encounters a stop signal and the starting position (when the door is closed), and it will pause for a while when it encounters the bottom position signal (when the door is fully open), and then automatically execute the closing action. Assume that x1, x2, and x3 represent the open, close, and stop control signals respectively; x4 represents the signal sent by the sensor when the door encounters an obstacle during operation; x5 indicates that the door is fully closed; x6 indicates that the door is fully open. COUT is the timing control signal inside the controller (here it is assumed that the pause time of the three pause states is the same).

s0 indicates the state of the electric door at zero position, at which time the electric door is in the closed position; s1 indicates the state of the electric door opening, the motor is rotating forward; s2 indicates the state of the electric door closing, the motor is rotating reversely; s3 indicates the state of the electric door stopping, at which time the motor is required to stop rotating; s4 indicates the state of the electric door at the bottom position, at which time the electric door is at the critical position of opening; s5 indicates the pause state of the electric door when encountering an obstacle during the reverse process; s6 indicates the pause state of the electric door when encountering an obstacle during the forward process. Z1, Z2, and Z3 respectively represent the open, close, and stop control signals sent by the controller to the motor control circuit.

3.2 VHDL language design of automatic door controller

(1) VHDL entity description:

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

ENTITY door IS

PORT(

Clk,reset: IN STD_LOGIC;--clock and reset signals;

X1,x2,x3,x4,x5,x6:OUT STD_LOGIC;--switch quantity;

Outputs:OUT_LOGIC_VECTOR(1 TO 3);

Ten:OUT STD_LOGIC);

END by;

(2) Main control combined process part program

PROCESS(current_state,x1,x2,x3,x4,x5,x6)

BEGIN

CASE current_state IS

WHEN so=>comb_output<=’001’;

en<='0';

IF x1=’1’ THEN next_state

………………

ELSE next_state

………………

END IF;

4 Conclusion

The automatic control system introduced in this article uses advanced EDA technology, a top-down design method, and a design idea that is independent of the process, which allows designers to consider the implementation of the system more in the design, better simplify the system, and greatly shorten the system design completion time. EDA technology will be more and more widely used in automatic control.