The Research Of The Calibration Device Of The Friction Coefficient Test Vehicle For The Airport Runway

The runway friction coefficient test vehicle is a special equipment for the measuring of the friction coefficient on the airport runway, which can give the data for the determination that whether the runway is suitable for the landing or takeoff of the aircraft and whether the runway need repair. The force sensors in the friction test vehicle are the crucial components for the validity of the measurement. To eliminate the influence of the floating error of the sensors and ensure the accuracy of the measurement, a periodic calibration for the friction coefficient test vehicle is needed. The calibration device of the friction coefficient test vehicle is a special equipment for the calibrating of the friction coefficient test vehicle.After comprehensive analysis of the current researches on the calibration device of the friction coefficient test vehicle and the application needs of this device in the domestic airports, A new type of calibration device based on PC104 is developed. The calibration device can perform the loading control and the calibrating of the horizontal force together with accurately calibrating of the vertical force. To cope with the nonlinear property of the output signal of the force sensor, least square method data fitting method and support vector regress (SVR) algorithm are applied together, By using of the sector least square method in sensor data fitting, the measuring accuracy of the sensor data is improved. The modeling analysis of the mechanism in the horizontal loading system shows that it can be simplified as a second-order system and the inertial frequency of it is higher than that of the step motor; Considering that the horizontal loading control system is an inertial system, the numeric PID control algorithm is used to adjust the response velocity of the system; The simulation of the step response of the control system with PID together with the test curve of the horizontal loading verify the effectiveness of the control algorithm for the improvement of the system's control quality. In addition, The Object Oriented Programming(OOP) method is used as the method of software design, and some class function modules are defined and realized for horizontal loading control and calibration, the vertical force calibration, the query and record of fitting parameters, the display of the loading curve respectively. Finally, The debugging work of the software and hardware shows the solution of the calibration device is correct and feasible.