We first analysis and model the stick failure of hydraulic valve and propose a new non - sensor detection method . we verify its validity by simulation and practical experiments . the experiment shows that this method can well identify the stick failure and do pre - diagnose 论文首先对液压阀卡涩、卡紧这一类重要故障现象进行了机理分析和建模，提出了基于电反射的无传感器检测新方法，并通过仿真和具体实验对其有效性进行了验证。
