ABSTRACT
In order to improve the tracking accuracy and ensure the accurate tracking of the car, it demands to get the precise description of the trajectory of the front vehicle first. After getting the discrete points of leader’s movement, 6×6 UGV needs to finish tracking through these points. It needs a curve fitting method to the trajectory. To overcome the deficiency of piecewise linear interpolation and single higher-order polynomial interpolation, the piecewise polynomial method can be used. That is, the lower conic section is getting via piecewise polynomial Interpolation, and is connected under certain conditions. Cubic spline is a good trade o. Cubic spline has its second order derivative which ensures a continuous first derivative [5]. So the heading angle is continuous. However, the commonly used spline function is expressed by, the following problems will be occurred:
1 When considering point-group P i (x
essary condition that using a cubic spline function to fit curve is: x
which Fig.3 (a) is shown, the condition is not met. 2 If the point-ground includes two points (x
(x j , y
to the X axis, the slope of the curve is considered as infinity.
