With the widespread application of WIFI networks and embedded system technology, the device monitoring system based on Embedded System and wireless network came into being. In this paper, we introduce a device monitoring system based on ARM upper computer and WIFI transmission, and we tested this system on workshop equipment. The hardware adopts ARM Cortex-A8 processor architecture of TI company as the main control chip, using IAC-335X-Kit development board for system design, external USB camera module and WIFI wireless module for video capture and data transmission. The software is based on embedded Linux as the platform. The system will collect production data accurately and objectively, and the statistical analysis. At the same time, the system uses QT to develop the upper computer software GUI interface. Compared with the traditional system based on the wired network, our design is more convenient and flexible, which reduces the implementation restriction and maintenance cost of traditional network cabling.
With the development of wireless network technology, the transmission of network information becomes more secure and convenient. WIFI has become the mainstream standard of wireless network access because of its wide coverage, high reliability, fast speed, no wiring, health and safety. And with the increasing demand for applications based on WIFI technology, more and more electronic products will provide WIFI wireless access function, which will have a very far-reaching impact on the application of wireless WIFI technology [
Based on the above understanding of WIFI transmission technology, Our main contribution is that the system is based on the maturity of wireless network technology and the universal application of various sensors to reduce the implementation limitation of traditional wired network communication, and the system is applied to verify in the new environment of workshop, in order to increase the hands of enterprises or workshop managers on production. Control ability improves production efficiency and enterprise profit.
The main technologies involved are video acquisition and transmission and WIFI wireless communication. Video capture device uses common USB interface cameras to connect directly to the ARM server. Video frame acquisition is realized through the interface provided by V4L2 driven by Linux kernel, and real-time display is achieved after data format conversion [
The rest of this paper is organized as follows: in Section 2, we describe our overview of system design. Section 3 presents the system software design in detail, which includes the function design of wireless communication module, the design of database structure and function and the software interface design of upper computer. Section 4 shows the implementation details of the system. In Section 5, we discuss the system operation and testing. In Section 6, we review related work and the conclusion is drawn in Section 7.
The design structure of the system is shown in
In hardware, the ARM server connects video acquisition device and wireless network card device through USB interface, realizes video acquisition and wireless communication based on WIFI. The WIFI network adopts central network architecture and uses wireless AP as access point to realize wireless communication between equipment and server.
Wireless communication adopts client-server communication mode based on C/S architecture. Devices as client clients are simulated by PC software, and ARM servers are servers. TCP protocol is used to realize network communication [
As shown in
The PC-side software simulates the client device and initiates the connection to the ARM server. When the server receives the connection request from the client, it will save the client in the list and send the command of requesting data to the client in the list regularly. Request commands are encapsulated and packaged by HDLC protocol customized by the company. After the client receives the request data from the server, the original request command is decomposed according to HDLC protocol, and its checkout and control commands are judged. If correct, the client replies real-time data to the server. Otherwise, it will continue to wait for the request of the server.
The real-time data returned by the client is also encapsulated by HDLC protocol. The server decomposes and judges the received real-time data. When the transmission is correct, the real-time data is converted into intuitive data to display and save. In addition, the real-time data sent by each client includes not only the device parameters, but also the corresponding IP address of the device and the corresponding time of the data, so as to realize the synchronous monitoring and control of multiple devices by the server.
Next, we introduce our database structure and function design, which mainly includes database logical design and database physical design. As an open source embedded database product, SQLite has the characteristics of low system overhead and high retrieval efficiency. At the same time, it is a zero-configuration database, without installation and management. A complete SQLite database is stored on a single disk file, self-sufficient, without any external dependencies. In addition, the development of the QT framework used to support SQLite is better, so the final database selected SQLite.
As a cross-platform C++ GUI library, Qt is developed by Troll Tech, Norway. With its object-oriented, easy to expand, component programming and cross-platform features, Qt is widely used in GUI interface development of embedded systems. Excellent cross-platform characteristics, programs written using Qt class can be compiled by different compilers to generate programs running on different platforms, which greatly reduce the difficulty of cross-platform development. Therefore, this design uses the embedded version of Qt, that is, the
Primary | Field name | Data type | Length | Accuracy | Unique | Noempty |
---|---|---|---|---|---|---|
No | Varchar | Yes | Yes | |||
Area | Varchar | |||||
Name | Varchar | |||||
IpAddr | Varchar | Yes | ||||
PresetA | Int | |||||
PresetV | Float |
Primary | Field name | Data type | Length | Accuracy | Unique | Noempty |
---|---|---|---|---|---|---|
Edate | Date | |||||
Etime | Time | |||||
Evoltage | Float | |||||
Ecurrent | Int |
Qt/Embedded development framework based on Frame buffer to develop the upper computer software interface [
As shown in
The following content is to set up four modules of the whole interface through tabWidget. Among them, the four module interfaces inherit from QWidget as a separate interface class. All of them are used to encapsulate the sub-components needed by the module and complete different information display.
TabWidget->setFocusPolicy(Qt::NoFocus);//The aim is not to set the focus and avoid dotted boxes
TabWidget->setTabPosition(QTabWidget::South);//Settings are placed below the interface
TabWidget->setFont(QFont("msyh",16));
PlantGlobal Widget=new PlantGlobal Widget(this);
TabWidget->addTab(plant global widget,tr("workshop status");//The following four sentences describe the four modules
InfoShowWidget=new InfoShowWidget(this);
TabWidget->addTab(infoShowWidget,tr("Information Display");
InfoCollectWidget=new InfoCollectWidget(this);
TabWidget->addTab(infoCollectWidget,tr("Information Summary");
Networking Widget=new Networking Widget(this);
TabWidget->addTab(networking widget,tr("network settings");//Initialization server sends instruction packages of request data to connected clients at regular intervals. The instruction data is the same
Void initRequestData();
//Data is processed by HDLC protocol in the company during network transmission
QByteArray data to HDLC(QByteArray data);
Void HDLCToData(QByteArray&enciphered Data);
QStringList convertReceive Message(QByteArray&array);
//The goal is to get the QTcpSocket connected to the server, that is, the socket created by the client
Void getClientSocket();
Void receiveMessage();//The server receives messages from the client
Void sendMessage();//The server sends a message requesting data
Void sendMessage Data(QStringList);//The server replies to data
Void disconnectSlot();//Signal Processing for Disconnecting Client
We run experiments with the following configurations:
1) Hardware:
Windows PC, Hangzhou Qiyang IAC-335X-Kit ARM development/evaluation board, QY-AT070TN83 LCD touch screen, USBHub hub, USB interface video acquisition module, RT3070 USB wireless network card.
2) Software and development environment:
Qt for Windows development tools, Ubuntu 14.04, Keil for arm, Sqlite 3 database, Qt 4.8.2 for ARM embedded development environment, tftpad 32 burner.
The physical connection of our hardware is shown in
Nowadays, WIFI transmission has different applications in various fields. Guo et al. thought that wireless transmissions are a potentially powerful and widely available source of transmissions for passive radar detection, and this work shows that this technique has considerable promise for a low cost and widely deployable detection and tracking system [
Function description | Show the overall status of workshop equipment | ||
---|---|---|---|
Test purpose | Test network communication and add and jump function of device button | ||
Prerequisite | Normal boot-up operation of the system | ||
Input/Action | Expected output/response | Actual output/response | |
Test 1: Normal start-up operation | Interface shows all device buttons and add buttons in the corresponding workshop database | Same as expected output | |
Test 2: Delete the database and start the system | The interface only shows the add device button | Same as expected output | |
Test 3: The client device successfully connects to the server and sends analog data | The color of the button corresponding to the device in the interface is displayed in different states according to the data rules | Same as expected output | |
Function description | Display the parameter information of the specific equipment, curve drawing and video playback | ||
---|---|---|---|
Test purpose | Test real-time data synchronous refresh, curve drawing, and video surveillance and server analog control of client devices | ||
Prerequisite | Successful connection between client and server | ||
Input/Action | Expected output/response | Actual output/response | |
Test 1: Client Keep Data Sending | Dynamic Drawing of Curves in Real-time | Same as expected output | |
Test 2: Click on the Video Monitoring tab button | The interface is switched to video surveillance. If a camera is inserted at this time, the captured video interface will be displayed. Otherwise, no video capturing device will be detected | Same as expected output | |
Function description | Statistical inquiry of workshop equipment status, running time and alarm information | ||
---|---|---|---|
Test purpose | Real-time Synchronization of Test Equipment Status and Writing and Query of Database | ||
Prerequisite | Normal operation of program | ||
Input/Action | Expected output/response | Actual output/response | |
Test 1: Change the state of a device | Change of the corresponding state in the statistical region of equipment status | Same as expected output | |
Test 2: In the alarm information statistics interface, select the specified date and equipment number, and click on the query | List the corresponding alarm records of the equipment below, and give prompts if there is no data record | Same as expected output | |
In this paper, the system uses ARM processor as the main control chip, embedded Linux system as the software platform, and uses QT to develop the GUI interface of host computer software. Compared with similar products, this design has the advantages of using embedded system as a server, low power consumption, small size, high integration, low cost, customizable, tailorable and a series of other advantages make it more suitable for factory workshop production environment. In addition, WIFI wireless communication is more convenient and flexible for data transmission. Compared with the monitoring and control system based on wired network, it reduces the implementation limitation and maintenance cost of traditional network wiring and reduces the cost investment of enterprises.
The authors declare no conflicts of interest regarding the publication of this paper.
Zhao, M.B., Yan, S. and Miao, Q.R. (2019) A Device Monitoring System Based on ARM Upper Computer and WIFI Transmission. Journal of Computer and Communications, 7, 72-82. https://doi.org/10.4236/jcc.2019.79006