Grader and blade control method

A blade control method of a grader, wherein the grade comprises a blade mechanism, a blade adjusting mechanism, a blade position detecting mechanism, and a motion trajectory library, the blade mechanism comprises a blade, a body frame comprising a plurality of adjusting means respectively corresponding to at least two degrees of freedom of the blade, a swing frame having a first end rotatably connected with the body frame, and a rotary support rotatably connected with a second end of the swing frame, the plurality of adjusting means comprise:

• a left lift cylinder and a right lift cylinder vertically arranged on left and right sides of the body frame respectively, the left lift cylinder and the right lift cylinder being connected between the body frame and the second end of the swing frame and configured to drive the swing frame to pitch relative to the body frame;
• a tilt cylinder, connected between the second end of the swing frame and the body frame and configured to drive the swing frame to side-swing;
• a rotary motor, connected between the second end of the swing frame and the rotary support and configured to drive the rotary support to rotate relative to the second end of the swing frame;
• an offset cylinder, connected between the blade and the rotary support and configured to drive the blade to slide relative to the rotary support;
• and
• an angle cylinder connected between the rotary support and the blade to drive the blade to rotate relative to the rotary support;
• and wherein the blade control method comprises:
• detecting a slope parameter for characterizing a spatial position of a blade by a blade position detecting mechanism;
• calling a corresponding motion function in a motion trajectory library according to a set operation condition and a required slope;
• and
• controlling at least one of a plurality of adjusting means in a blade adjusting mechanism according to the slope parameter of the blade and the motion function;
• wherein the step of calculating a slope parameter of the blade according to the rotation angle and each displacement by referring to a current operation condition of the grader comprises:
• if the current operation condition of the blade is a flat shoveling operation condition, calculating a first angle α of the blade by a preset first motion function, and calculating a second angle β of the blade by a preset second motion function, wherein the preset first motion function is:
• α=K1*X1+K2*X2, the preset second motion function is:
• β=K6*X6;
• if the current operation condition of the blade is a scraping groove operation condition, calculating a first angle α of the blade by the preset first motion function, and calculating a penetration depth H of the blade by a preset third motion function, wherein the preset third motion function is:
• H=K1*X1+K2*X2+K4*X4;
• and
• if the current operation condition of the blade is a scraping slope operation condition, calculating a third angle θ of the blade by a preset fourth motion function, wherein the preset fourth motion function is:
• θ=K1*X1+K2*X2+K3*X3+K4*X4+K5*X5+K6*X6,
• wherein K1, K2, K3, K4, K5, and K6 are all motion coefficients after calibrating a plurality of adjusting means, the first angle α is an included angle between a lower edge of the blade and an operation surface of the grader, the second angle β is an included angle between the scraping surface of the blade adjacent to the lower edge and the operation surface, the penetration depth H is a distance between the lowest position of the blade and the operation surface, the third angle θ is an included angle between a side slope formed after scraping slope by the blade and a horizontal plane, X1 is a displacement of the left lift cylinder, X2 is a displacement of the right lift cylinder, X3 is a displacement of the tilt cylinder, X4 a displacement of the offset cylinder, X5 is a rotation angle of the rotary motor, and X6 is a displacement of the angle cylinder.