Based On Ethernet Technology, Strain Measurement System

A Strain Measuring System is designed, based on Ethernet, featured with telecontrol and digitalization. There are two parts: Field Measuring Node and Distant Controlling Terminal. The Field Measuring Node receives signal from the strain sensor, does conditioning to it according to the commands from the Distant Controlling Terminal, and then uploads the measuring results to the Ethernet. On the other side, the Distant Controlling Terminal takes charge of the Field Node by starting its zeroing, sampling, also by setting its parameters such as power of bridge, amplifier multiple, cut frequence, sample frequence. The Terminal downloads the results from the Ethernet. The Terminal and more than one Nodes communicate on Ethernet, with data and commands transmitted on it.PIC16F876, an 8-bit Single-Chip-Micyoco from Microchip Technology, is implemented as the MCU of Field Node. It controls the hardware of amplifier, filter, zcroing circuit, A/D converter to work cooperatively and intelligently. Data is transmitted by its Serial Communication Interface. To be suitable for Ethernet, data in SCI is packeted and transmitted continuously. Internet Device Access Server—ZNE-100T facilitates Field Measuring Node with Ethernet function. The firmware of the Node is developed in C language. PC works as the Distant Controlling Terminal. Its application software is developed in Visual C++ 6.0 and Windows Sockets, to provide the users' operating interface of receiving and sending data.The detail design of the whole system and the experiment are shown in this dissertation.