Design And Development Of Automobile Reversing Radar Based On Embedded System

With the automobile penetration increases every year, consumers buy the automobile as a mean of transport at the same time, for the safety of motor automobiles have higher requirements. The most common drivers'driving behavior, the reverse traffic accidents caused by a minority, triggering major accidents has occurred from time to time, to lay a major hidden safety. In order to resolve the security issue, Automobile Reversing Radar ('ARR') was developed, more and more businesses have entered the market. The full name of Automobile Reversing Radar is " Automobile Reversing Anti-collision Radar", also named "parking assist device" .It is a parking assist device for the car, reminding the drivers attention to the information from the situation around the obstacles by voice or video.And it can resolve the driver parking and starting the automobile's trouble, helping the driver to remove the dead line of sight, and blurred vision defects and improve safety. Reversing radar's primary role is that when the driver reversing, he didn't need to look back to know what's the barrier after the automobile.It's so easier and safer. At present, only some of the high-end automobile equipped in the country with reversing radar, and more automobile's brands in this area is still vacant. The subject of the article was designed a radar for the middle-end and low-end automobile on the market, as a low cost, high flexibility, high reliability and easy control.In this topic, Embedded System is reversing radar system of the core technology. Embedded system is based on computer technology, which aims to cover the actual production and life applications. Through its system, software and hardware can be configured to create a strict power, cost, size, functional and reliable professional systematic. It can control other devices, monitoring, management and more. Embedded system include two parts : hardware and software. Hardware includes processors, microprocessors, memory, peripheral devices and graphics controllers. It is the physical basis of the system, it provides an interface for the operation platform of software to communicate with other devices. Software components include operating system, software and application programming, providing a method to control the system.With the rapid development of modern semiconductor technology, microelectronic technology and advanced computer technology, it conforms a variety of technology applications and create a high degree of application Embedded System, which is a technology-intensive, capital-intensive, highly dispersed and innovative new type of integrated knowledge system. This system is a continuous development of new technologies with the times. Through the continuous development of Embedded System, it deepens the process of industrialization, and has been widely used in everyday information and communication, business industry, national military, daily life office and other fields.Automobile reversing radar was designed based on the ultrasonic positioning technology. The wavelength of ultrasonic sound waves must be shorter than other waves, and easy to directional emission with good direction, intensity, good control. The speed of Ultrasound is slower than the light and it is easy to calculate the travel times.So it has been widely used in ultrasonic distance measurement, speed measurement, cleaning, welding and so on. Ultrasonic technology means that transmit a wave through the air. It can not be heard by human ears according to the time of reflected back from the barrier and acoustic intensity to determine the kind of the obstacles or the distance of method.Combining the characteristics of embedded system, the design choices AT89C51is regarded as the main control chip. Ultrasonic detector can transmit and receive ultrasound echo.If one uses a microcontroller to record from the time of ultrasound emission, transmitting and receiving by the interval between the time. According to the ultrasound transmit under the acoustic propagation velocity in the air, you can calculate the distance between the ultrasonic detection devices and the barrier. When the ultrasound probe receives echo signal, the wave will be sent to the comparator after amplification and shaping and the comparator's output will become high.This signal is used as a request signal when the microcontroller needs to be interrupted. Once received the request signal, the microcontroller will read the recorded time, and then send the result to the digital LED (LED digital displays dynamic scanning method to achieve).While the signal triggered voice module circuit, repeat launch, receive, display and voice prompt until the car exit the software process.Reversing radar hardware circuit designs include microcomputer systems ,display circuit, ultrasonic transmitter, ultrasonic detection, receiving circuit, reversing control signal circuits, and voice circuit.Automobile Reversing Radar software designing include the main program, send subroutine, receive subroutines, alarm program, LED display program and so on. Program design ideas—the completion of the timer, interrupt system and a variety of initialization parameter settings, issued 40 KHz square wave signal, waiting to receive interrupt subroutine, distance subroutine, voice prompt and control signals simultaneously.In general, the task of designing need repeated debugging. We use the software of KEIL and PROTEUS to simulate the correct procedure. When the procedure is successful, then we can do actual experiments. This can speed up the development progress, but also can save the hardware resources. Hardware and software co-simulation debugging is completed; the compiled program need to make a test in the microcontroller. Running and debugging is based on problems that arise in repeated changes to the measurement errors,which arises during the experiment many times and repeat the consistency analysis through the system of continuous optimization .In this topic, automobile reversing radar was designed for the general close-ranging requirements. The construction cost of the system is lower, cost-effective is higher. To conduct an effective means of traffic management and tools, it can improve the accuracy of automobile detection distance. It is conducive to the scientific management of transport and reduce the quality of drivers requirements. This design can be a good helper for the drivers. It can effectively reduce and avoid that poor vision of large automobiles drivers such as refrigerated trucks, container trucks, garbage trucks, food trucks, buses and so on. It is particularly suitable for reversing and parking in the night. In the course of their daily driving, it played a good supporting role.