| The centralized measurement method of analog signal remote transmission is still widely used in the static test system in which a lot of strain gauges are installed on the surface of the airplane's body to obtain deformation data nowadays. Of course, one airplane demands large number of strain gauges and intensive distribution, so it needs a lot of cables to connect to the strain gauges, sometimes the number is even more than tens of thousands. It brings great trouble when place the cables which also increase the error rate in worker's connecting.In order to reduce the complexity of the site layout, this paper puts forward a new solution. The intelligent terminal nodes use the strain gauge to measure the deformation data. The bus driver controller uses two wire serial buses to promise on the one hand it can achieve the data transmission between the bus driver controller and the terminal nodes, on the other hand it provides the power supply to the terminal nodes.The research of this paper is to design bus driver controller with seven two-wire interfaces, and the bus driver controller can transmit data that collected from the terminal nodes to the server through Ethernet. At the same time, the function of time synchronization is added to offer timestamp to the measurement data information. XY·CN bus in this paper is used to solve the problem of power supply and data transmission of nodes at the same time, which need not to distinguish the polarity when the terminal node connect to the XY·CN bus. This design can reduce the human error effectively. XY·CN bus uses data formats of asynchronous serial communication when transmitting and receiving data. The main controller of this system is TM4C1294 NCPDT that is based on ARM Cortex M4 architecture. Using TM4C1294 NCPDT Ethernet function and combined with embedded Ethernet LwIP protocol stack, the bus driver controller can be designed as a TCP/IP client and transmit the terminal node data to LAN server by Ethernet packets. |
PDF Full Text Request