A novel method for computer-controlled condition monitoring of hydraulic systems

This research is focused on the investigation of determination of the hydraulic pressure without the need for the insertion of pressure gauges or sensors into the oil pipes. The development of a novel computer-controlled non-intrusive pressure monitoring system is presented based on the ultrasonic techniques. The pressure readings can be taken by the determination of the ultrasonic velocity travelling through the oil. The measuring scheme for the velocity which is a combination of the pulse echo and the pulse transmission methods could eliminate the thickness influence of the pipe on the measurement of velocity and effectively remove the unexpected acoustic and electric time delay. The design of the computer-controlled monitoring system including hardware design and software design is briefly stated. The relation between the pressure and the ultrasonic wave velocity is provided. Testing results are given, which indicate that the accuracy of the monitoring system is better than ±2.0%FS.