Embedded-based automated distribution system

The automated management and operation system has become an indispensable part of modern enterprises. The video image transmission monitoring system has been widely used in important occasions such as transportation, hospitals, banks, homes and video conferences. The early analog video monitoring system could not be connected to the Internet and could only communicate with the management center point-to-point. With the development of image and video processing technology, network technology and automatic control technology, the video image system has transitioned to digital network transmission. It takes the compression, transmission, storage and playback (playback) of digital video as the core, adopts advanced digital image compression encoding/decoding technology and transmission technology, and uses intelligent image processing and recognition technology for image display, adjustment and tracking. It tracks and identifies objects according to the on-site environment and analyzes and processes images.

　　1. Composition of automated distribution system

　　This system is based on the image acquisition subsystem of the USB camera, the ARM processor subsystem and the wireless network data transmission subsystem to form a video server system. The data exchange and transmission with the management center is realized through the GPRS module on the Samsung S3C2410 development board. The image data is received through the USB camera, the shelf position is located and identified, and then the identification information is sent to the distribution management center through the GPRS module device. The management center sends a control command to the distribution vehicle to place the goods on the distribution vehicle to the designated shelf position, or take the goods from the designated shelf position and load them onto the distribution vehicle. As shown in Figure 1.

　　2 Hardware Implementation of Video Server System

　　The network video server in the above figure is mainly composed of a USB camera, a network video server, etc. Its workflow is shown in Figure 2.

　　2.1 ARM Embedded Microprocessor

　　The embedded microprocessor is the core of the hardware part, and it uses Samsung's ARM microprocessor S3C42410. This microprocessor has a built-in 16/32-bit ARM9TDMI core, can execute 32-bit ARM instructions or 16-bit Thumb instructions, has an operating frequency of up to 203 MHz, provides 8 K bytes of cache, and 2 full-duplex UART (Universal Asynchronous Receiver and Transmitter) channels, and has the characteristics of low cost and high performance.

　　2.2 Wireless Communication System

　　With the development of GPRS technology in the field of wireless communication, the use of GPRS modem in ARM systems to achieve Internet access has also begun to be applied. GPRS can play the characteristics of always online, fast login, and traffic-based billing. This paper uses the AT command to dial in the embedded real-time operating system ARM CPU. After the response is fed back, a data transmission channel, namely the GPRS network, is established between the GPRS modem in this system and the Internet, thereby realizing data interaction between the delivery vehicle and the monitoring management center, and realizing remote unattended automated delivery.

　　2.3 Video Capture and Compression Module Design

　　The video acquisition and compression module consists of two parts: video data acquisition and video data compression. The video data acquisition chip is responsible for collecting the analog video data sent by the USB camera and performing analog-to-digital conversion, compressing it in MPEG4 format, and then storing the data in the buffer memory through the data bus for processing by S3C2410. The compression chip uses VW2010, which is a commonly used real-time audio and video compression/decompression chip, compatible with MPEG-1, 2, 4, H. 263 standards, with high practicality and cost-effectiveness, and can capture and compress video signals in real time and dynamically at a sampling rate of 25 or 30 frames per second.

　　3 Software Structure and Implementation of Automated Distribution System

　　3.1 Software Structure

　　The embedded Linux operating system and application programs are run on the video server. The server-side software development adopts the C/S mode. The main function of the video server-side software is to collect, compress, store, and transmit the images captured by the camera. When the operating system is started, the real-time clock is started, the system loads the serial port, USB and other driver modules, waits for the completion of video image acquisition, and then repeats the operation of collecting and sending pictures.

　　3.2 Client Software

　　The client refers to the management center, which can receive data transmitted from the video surveillance server. Its functions mainly include receiving images, data analysis, and file storage through the GPRS network. When the client (management center) receives the data, it first analyzes the intercepted data according to the protocol data specification, strips off the protocol header, analyzes the lower layer data, and proceeds layer by layer until the final image data is obtained, and then counts the information and traffic in it, and then stores these two parts of information or transmits them to the corresponding display module. In the automated distribution system, the monitoring center uses images to determine the location of the distribution vehicle, the size of the object to adjust the robotic arm, and assemble the goods.

　　4 Conclusion

　　The automated distribution system based on ARM embedded system has strong anti-interference ability and is suitable for long-distance transmission. Based on the real-time operating system Linux, it has small size, low power consumption, strong reliability, easy installation, and strong real-time performance, allowing managers to realize real-time operation of distribution vehicles at a distance. The wireless network GPRS technology is used to realize the transmission of video signals, and the command and dispatch of the entire automated distribution system can be realized at any location in the network.