Parking lot management system based on 51 single chip microcomputer

The actual picture of the parking lot management system designed by 51 single-chip microcomputer:

Design and development of parking lot vehicle management system

Abstract: With the rapid development of science and technology, transportation is becoming more and more popular. As one of the most important means of transportation in human society, cars play a significant role. With the improvement of people's living standards, the number of cars is also increasing day by day, so parking is becoming a global problem. The backward manual parking management in the past is about to be replaced by a high-tech automatic parking management system. The highly automated parking management system saves a lot of time and manpower and material consumption, and greatly improves efficiency.

This paper introduces a parking lot management system controlled by a single chip microcomputer. It can calculate the number of vehicles that can be parked at any time based on the available parking space, and automatically and reliably complete the entry and exit of vehicles. It can also display whether there is a parking space and whether there are vehicles entering or leaving the parking lot.

This design has the advantages of simple structure, accurate counting, high economic benefits, low cost, high reliability, convenient maintenance, short development cycle, simple operation, etc. Experiments have proved that the software and hardware design of this system is reasonable, and the performance is good. After system expansion and upgrading, it can effectively meet the needs of various traffic statistics.

•   Preface
  

1.1 Background and significance of the study

With the economic growth and the acceleration of urbanization, cars have entered families and private ownership is increasing. Investigations and studies have found that many communities have certain limitations in parking management. In order to facilitate and effectively implement the community vehicle management system and make the community parking lot safe and fast, a comprehensive community vehicle statistics and counting system must be equipped.

Single-chip microcomputers (MCUs for short) are also called microcontrollers. Since their introduction in the 1970s, they have developed rapidly. From the early 8-bit machines to the current 32-bit machines, their hardware and software resources have been continuously enriched and improved. MCUs have become an important member of the computer world due to their high integration, small size, strong anti-interference ability, low price, and unique control functions. In an application system, only one MCU is used. However, the significance of MCU applications is by no means limited to its wide range and the economic benefits it brings. More importantly, the application of MCUs is fundamentally changing the traditional control system design ideas and design methods. Most of the control functions that had to be implemented by analog circuits or digital circuits in the past can now be implemented by MCUs through software (programming). This control technology that replaces hardware with software and improves system performance will continue to develop and improve with the popularization of MCU applications.

With the development of society, the importance of data statistics is also very significant. It is a bridge connecting computers with the external physical world. It is a key step in statistical management. It plays an important role in the modern information field and is an indispensable part of information products. Therefore, it is meaningful and necessary to choose the design of a data flow statistics system based on a single-chip microcomputer.

This design is a vehicle flow statistics system controlled by a "single chip microcomputer". With the growth of the national economy and the improvement of people's quality of life, private cars have gradually entered people's lives, but the problems that follow are also in front of people, that is, the space in the city is becoming more and more tight, and parking spaces are hard to find, especially on statutory holidays when you go out for a self-driving tour, you enter the parking lot and find that it is full, so you can only find another parking space. This design is designed to address such problems. This design can not only intuitively display the traffic flow of the parking lot, but also issue an alarm when the parking space is full. It is not only convenient for car owners to understand the parking space situation in the parking lot and make appropriate choices, but also convenient for the management of the property company.

The design is inexpensive and accurate in counting, and can be widely used in parking lots, shopping malls, real estate companies, property management departments, etc. Due to the price advantage, safety, and the reduction in management costs after a large number of applications, China has a large population, so it is conceivable how much economic value it can create for product manufacturers.

1.2 System Overview

The system includes: power module, sensor module, display module, manual keyboard input module, vehicle parking space simulation module, etc. It can realize the functions of control opening, displaying the number of existing vehicles in the parking lot and the number of vehicles parked, manually setting the total number of parking spaces and the numerical display of the remaining number of parking spaces, etc. It also has 16 simulated parking spaces to display the specific location of the vehicle parking.

Features of the system:

(1) Since this system uses electronic components, no manual management is required.

(2) Automatically display the parking space status of the parking lot and the statistics of vehicles entering, exiting and parked.

(3) Count the total number of vehicles parked in the community on that day and display their parking locations.

(4) This system is applicable to any parking lot.

(5) Detect whether the parking spaces in the community are full and the alarm indicator light flashes.

The simulation block diagram of the system:

Section 2 Scheme Design and Selection

The system is used to detect whether there are vehicles entering or exiting, and whether there are vacant parking spaces. The single-chip microcomputer is used to control other modules to realize the addition and subtraction counting and status display of the number and status of vehicles, and the timing system in the single-chip microcomputer is used to limit and set the time for vehicles to enter and exit. The input of the keyboard system can manually control the display of the total number of parking spaces and the number of remaining parking spaces.

2.1 Design of power module

The main function of the power module in the entire system is to provide stable voltage.

Solution 1: The power module in the whole system mainly provides stable voltage. The circuit inputs single-phase 220V AC power, passes through the transformer, full-bridge rectifier, and outputs stable 5V DC power after voltage stabilization.

Solution 2: This circuit is powered by USB 5V directly, and can be directly connected to a power adapter with a USB interface! It has the advantages of few external components, easy use, stable performance, and low price, so it is widely used. Because this system is designed to output a 5V voltage.

To sum up: In order to simplify the circuit and make it easy to use, we use a very mature power adapter to supply power. Directly connect the adapter power supply 5V.

2.2 Sensor selection

Solution 1: The ultrasonic sensor sends out sound waves, and when a car passes by, the time consumed by the reflected sound waves is calculated. In this way, it can be judged whether a car passes by at different distances. The advantages are high accuracy, small and convenient. The disadvantages are that it is more complicated to use and not easy to install.

Solution 2: Use infrared photoelectric sensors. If there is an obstacle passing by within the measured distance, it will output a high level. If there is no obstacle, it will output a low level. This makes it easy to determine whether a car is passing by.

To sum up: We adopted solution 2 and directly used photoelectric sensors to determine whether a car was entering.

2.3 Selection of main chip

Solution 1: Use 8-bit microcontroller. The typical representative of 8-bit microcontroller is 8051 microcontroller. 8051 microcontroller is an entry-level microcontroller with simple core, wide application and complete information, which is very suitable for entry-level learning. At the same time, it is cheap and is suitable for electronic products that pursue low cost but not real-time performance. For a long time in my country, 8051 microcontroller has occupied the small home appliance market, and the reason is its ultra-low cost.

Solution 2: Use a 16-bit microcontroller. The MSP430 microcontroller is a 16-bit microcontroller known for its low power consumption. It has many low-power working modes, uses a reduced instruction set (RISC) structure, has a rich addressing mode, and highly efficient table lookup processing instructions. These features ensure that it can be used to write highly efficient source programs.

Solution 3: Use a 32-bit microcontroller. The Cortex-M0+ core is based on the ARMv6 architecture, supports Thumb/Thumb-2 subset ISA, is a single core, and is manufactured using a low-cost 90nmLP process. The core area is only 0.04mm2, and the current and power consumption per MHz unit frequency are 9μA and 11μW respectively, which is about one-third of other 8/16-bit microcontrollers today, and the performance is much higher than them. Freescale's Kinetis L series microcontrollers are based on the ARM Cortex-M0+ core and are the most energy-efficient 32-bit microcontrollers on the market. The data throughput per microampere is at the industry's leading level; ultra-low power mode has a variety of flexible power modes suitable for different application scenarios to maximize battery life; multiple technologies optimize power consumption, including 90nm thin film storage (TFS) technology, clock and power gating technology, and an efficient platform with a bit processing engine, peripheral cross bridge and zero-wait flash memory controller; in deep sleep mode, intelligent decisions can be made and data can be processed without waking up the core.