Design Of Communication Network For Distributed On-line Monitoring Vibration System On Basis Of CAN Bus

The vibrant conditions of a ship can be used to diagnose the operating charactersof the equipments on the ship, monitoring vibration can provide reliable basis to findthe malfunction momentarily. Especially for special functional ship, its acousticcharacteristices may be affected by the vibrant noises so it is necessary to mountreal-time monitor network for vibration noise on ships.As being the bridge of data transmission, the reliability of communicationnetwork directly affect the reliability of the monitoring vibration system. In this peper,The CAN bus is selected to compose the communication network, the FCS (fieldbuscontrol system) is used to take place the conventional DCS (discrete control system).It has the following features: complete digitized signal transmission, thoroughlydiscrete of control functions and openness and mutual operation and so on. Thenetwork nodes can easily be extended by using of CAN bridge.The paper's content is introduced briefly as followed:1. The overall plan of distributed monitoring vibration network system isintroduced. DCS and FCS are compared and the CAN bus is selected tocompose the communication network.2. The multi-layer distributed network structure model including centralcomputer, net bridge and measure and process unit, sensors is establishedwhich is based on the feildbus technology and has the features of safety,reliability, easy expansion and strong real-time and so on.3. The procedures of the CAN netbridge including internal SPI interfaceprocedure and external CAN interface procedure are programmed.4. The communicate procedure of the certral computer are programmed.5. The experimental data communication network is built, the reliability ofthe network and the feasibility of the procedures are proved through theexperiments.