Research And Development Of Distributed Testing System Based On CAN Bus

It is necessary to develop certain high efficient digital measurement system to meet the requirements of new industrial applications. Based on CAN-bus, a strain measurement system, which combines DSP (Digital Signal Processor) with a virtual instrument tool (LabView), has been built. Several achievements have been made as following:1. High performance signal amplifier was designed and a PCB (Printed Circuit Board) for the amplification and filtering of 8-channel strain sensors was manufactured. The amplifier and the integrated board provide a pathway technique to large-scale strain measurement systems.2. A CAN-bus node that based on the CAN-bus 2.0A specification has been designed for potential practical applications. Test results show that the hardware can run stably with the software program.3. The communication between the CAN-bus node and the control computer was established using Lab View and c language. The GUI (Graphics User Interface) was designed with LabView and the kernel driver, which is written in C language. Experiments show that the testing node can communicate with the control computer properly.The test of dynamic strain history in fatigue experiments has been completed by integrating the above techniques. In the experiment all useful data were extracted and saved in the control computer.