Abstract: High speed on/off valve(HSV) is the core control component of digital hydraulic system(DHS). Dynamic characteristic is not only an important index to evaluate the performance of HSV, but also the key to ensure the control accuracy of DHS. However, due to the compact structure and small size of the HSV, traditional displacement detection method is hardly to directly measure its dynamic performance, which makes the accurate evaluation for the dynamic performance of the HSV a huge challenge in the field of digital hydraulics. The detection method for the dynamic performance of HSV based on vibration characteristic is proposed, the valve vibration model during the dynamic opening and closing process is established, the vibration law of the valve body is revealed, and the relationship between valve body vibration and switching status of HSV is studied, and the real-time measurement for the dynamic performance of the HSV is finally realized. In order to reflect the superiority of the vibration-based detection method for the dynamic characteristic of HSV, the HSV driven by three-voltage and four-voltage methods is tested, and the laser displacement sensor method is used to verify the results. The experimental results show that the measurement approach can accurately obtain the dynamic opening and closing time of the HSV without changing the internal structure of the HSV and without destroying its original dynamic characteristic. Compared with the existing testing methods, the vibration test method has the advantages of strong reliability, real time performance and economic benefits.

Key words: high speed on/off valve, digital hydraulics, dynamic performance, vibration characteristic