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Based on height deviation of scraper between laser signal height reference and scraper working height, height controller adjusts scraper's height by driving hydraulic cylinder.Scraper's height controlling accuracy is determined by height positioning accuracy and height positioning update frequency.Energy density of swept the laser receiver is inversely proportional to the rotational speed of Laser transmitter, increase the rotational speed of the laser transmitter the laser receiver's SNR would be reduced.Thus it is very difficult to achieve high-precision height controlling by only height deviation of laser signal.Based on attitude of the scraper and laser height deviation, method of integrated height positioning of laser leveler for paddy fields is studied.Scraper is fixed on the tractor flat with three point suspension mode, telescopic hydraulic cylinder dynamically adjust scraper working height, this would change the acceleration of scraper and the angular velocity rotating around the fixing fulcrum.With three-axis accelerometer and three-axis gyro, a MPU6050 module is fixed on the scraper rotary shaft, which dynamically detects rise or fall acceleration and angular velocity around the fixing fulcrum of the scraper by the hydraulic force.The data of three-axis accelerometer and three-axis gyro of MPU6050 module are read out by a stm32f103RBT6 MCU with 100Hz update frequency, after processed by Low pass filter,according to inertial navigation principle, the scraper's height moving track could be gotten and the scraper's height position also be dynamic estimated.Because photoelectric sensitive element of laser receiver is made by rectangular silicon photocell, receiving the laser signal, the height position also exist errors except some height point, which height position update frequency is normally 10Hz.When the laser height signals are the accuracy special points, the INS positioning accumulated error and estimation error would be eliminate directly;otherwise Kalman filter is used for data fusion of these two sets of data, the accuracy of height positioning error is reduced.In the laboratory guyed displacement sensor and the height combined positioning modular are fixed on the scraper rotary shaft, with a manual method the scraper is randomly controlled up or down,synchronous data are recorded by a computer, the experimental data show that under 100Hz update frequency with Guyed displacement sensor reference the height combined positioning error is less than three millimeter, meet the requirements of scraper height high-precision positioning.