Industrial Data Acquisition System Based On Self Organized Wireless Sensor Network

In modern industry, it has a profound influence on operating conditions and the stability of the system to ensure that the field data acquisition is accuracy, comprehensive and real-time. Data acquisition system has become an important mean to ensure quality, increase yield and exert economic benefit, which has been the core and foundation of industry control and monitoring system.Communication mode used by different data acquisition system is different, which can be described by covering ability, reliability, real-time, efficiency, construction and operating cost. This paper proposed a design scheme of industrial data acquisition system based on self-organized wireless sensor networks, which is contraposed to industrial field with a wide cover range, more sampling points and smaller amount of data acquisition. The system has the following characteristics: a wide coverage, high transmission efficiency, structural flexibility and reliability. Having selected user-end data acquisition system on heating network as application object, the subject demonstrate and study the structure of the system, self-organized protocol and the implementing schemes of system software and hardware.In the design of the self-organized network, network topology uses a hierarchical tree-cluster network structure depending on the application. The paper defines the network protocol format in detail, proposes wireless network as well as the solution to adding new nodes to the network. Finally, key issues, such as the network touting mechanisms and routing maintenance are solved.In this design, uses the STM32F103 CBT6 as core microprocessor and radio frequency chip nRF905 as the wireless core of transceiver modules. The system designs sensor node and sink-node. According to the function of each module, I extend peripheral interface circuit, design electrical arrangement, draw the PCB and make the PCB board then finish the prototype and the system designing. Embedded System uC/OS-Ⅱis the software and the operating system can be ported to STM32 hardware platforms . As request of the functions of sensor node and sink-node, I develop application software under the uC/OS-Ⅱ. Using the task-portitioning mode to finish the design of application. Each task completes one function, the information exchange between every function vias the semaphores of uC/OS-Ⅱand mailbox or other communication mechanisms.This issue tests various functions of the system through a since networking experiment, test results show that the system has the characteristics of simple and quick networking , efficient and reliable data transmission, etc. This system is suitable for the working system that communication distance is farther, coverage is wide, acquisition nodes are more and data nodes are less, such as factory condition monitoring, wireless metering, environmental monitoring, etc.