Aiming at the problem that sensor volume is large and the sensor distance is far from the measuring point in existing water film pressure monitoring of water-lubricated bearings
an intelligent water-lubricated bearing is constructed.That is
thin film pressure sensor is used and embedded into the bearing bush
and then
information processing unit and the control device are used to realize the on-line monitoring and control of running state of the bearing.However
thin film pressure sensor is difficult to calibrate by traditional methods because of its small volume
so it has become an urgent problem to be solved in research of intelligent water-lubricated bearings.A calibration method for thin film pressure sensor is proposed and a calibration system is established.The calibration system includes HLD pressure calibration device
sensor and pre-conditioning module
NI acquisition card and upper PC software
etc.RANSAC algorithm and least square method are used to fit the calibration data
respectively.Finally
error analysis is carried out on the calibration results.The results show that the fitting precision of RANSAC algorithm is higher than that of least square method
and the maximum relative error is 1.47 %
which proves the feasibility of the calibration method and the system.