Research On Node Energy Consumption Optimization Method Of Mechanical Vibration Wireless Sensor Networks

In the field of mechanical vibration monitoring,existing wired monitoring systems often have complicated wiring,high deployment costs,and poor maintainability when applied.Although wireless sensor networks can make up for the lack of wired monitoring,mechanical vibration signals have weak signals,high frequencies,and ranges It has the characteristics of wide range and large amount of transmitted data.Nodes need to have high-frequency acquisition,high acquisition accuracy,a large amount of data cache,and fast data transmission to quickly obtain a large number of high-precision vibration signals.While meeting these high-performance requirements,it will increase significantly Energy consumption;the nodes are often embedded in the equipment in the monitoring application.The lithium battery is used for charging,and the energy is very limited.After the nodes are arranged at the monitoring points of the equipment,it is difficult to replace the node batteries because of the particularity of the vibration monitoring environment.Therefore,under the premise of ensuring the performance of the nodes,optimizing the energy consumption of the nodes with very limited energy is a key problem that needs to be solved for the mechanical vibration WSN to achieve long-term stable monitoring.Data acquisition,storage and transmission are a cycle of the work of mechanical vibration WSN nodes,and the energy consumption of the nodes comes from these three links except the idle state.In the idle state of the node and the above three links,the factors affecting its energy consumption can also be subdivided into various types,such as the power system and front-end hardware of the acquisition node,Secure Digital Input and Output(SDIO)data reading mode,node transmission power in the data transmission process,multi-channel data transmission,whether the network topology is balanced,etc.This paper mainly studies the energy consumption optimization of mechanical vibration WSN nodes from the following three research points:(1)In view of the problems of the existing dual-core processor architecture of mechanical vibration WSN acquisition nodes with high idle energy consumption and multiple and scattered power supply modules,a low-power consumption method for the integrated design and energy consumption optimization of mechanical vibration wireless sensor network node power supply is proposed.First,in view of the existing node power supply is complex,the problem of high energy consumption,the node power supply system for low power consumption and integrated design,and analyzes main processor module,dual core collection node from the processor module and control chip peripheral circuit function modules such as the energy consumption situation,thus to software and hardware design of node working mode switching,analysis the energy consumption of the nodes in the data transmission data read,need according to the task of gathering node,in order to control core to standby or wake up,effectively reduce the mechanical vibration of the wireless sensor network to collect node energy consumption.(2)The SDIO process of node data reading is directly related to the size of data block.Mechanical vibration monitoring,has a wide range of frequencies,vibration signal node sampling frequency will increase,that in a short period of time will produce a lot of vibration data,50000 Hz sampling frequency,for example,in 1s can produce 150 k Byte length of data,for data transmission bandwidth limits,collected data can’t upload is stored in a Micro SD card first,then read through the SDIO vibration data,the processor STM32F405RGT6 for SDIO operation energy consumption is higher,so can according to the size of blocks of data read from the SDIO optimize the node energy consumption.(3)In view of the problem that the mechanical vibration WSN acquisition node cannot sense the link quality indication of communication environment and the high transmission power leads to the high energy consumption of data transmission,an optimal control method of transmitting power for mass data transmission in mechanical vibration wireless sensor network is proposed.Firstly,the discrete relationships between Link Quality Indicator(LQI)and packet loss retransmission rate,node transmission power and energy consumption required to transmit a single packet,and the types of mathematical models of node transmission power and LQI are determined through statistical experiments.Then,the least square method is used to fit the discrete data of transmission power and transmission energy consumption of the node.Finally,the transmission power corresponding to the minimum energy consumption is obtained according to the model optimization.The node only needs to send a very small number of packets before each data transmission,then the transmission power can be re-optimized and updated,so as to reduce the transmission energy consumption of mechanical vibration wireless sensor network.(4)Design of low power consumption monitoring system for wireless sensor network of mechanical vibration.Based on Microsoft C# programming language,the software of data monitoring management platform is designed,and the function modules such as node collection status reporting,power-saving working mode control,node disconnection and link quality monitoring are developed.Finally,the application of the developed monitoring system on the test bench of the gear transmission life prediction technology of typical aviation airborne equipment was tested to verify the effectiveness of the mechanical vibration WSN low power consumption monitoring system in the field of mechanical equipment vibration monitoring.Finally,the paper summarizes the work of this paper,and looks forward to the future research direction.