A method for segmentally constructing three-dimensional space alignment of highways using quartic bezier curves

Abstract

The invention discloses a method for constructing a highway three-dimensional space linear shape by adopting a quartic Bezier curve segmentation. The method for constructing the highway three-dimensional space linear shape by adopting the quartic Bezier curve segmentation comprises the following steps that S1, a segmentation control point sequence P (i = 0, 1, ..., n) are given, and a corresponding segmentation interpolation parameter t is determined; S2, a unified analytical expression of a quartic Bezier curve Gamma on the interval [t, t+ 1] is given; S3, the endpoint characteristic quantity of each segmentation control point P is calculated; S4, i section quartic Bezier curve Gamma containing degrees of freedom m or u and s is constructed according to endpoint conditions; S5, values are assigned to degrees of freedom m or u and s to obtain the Gamma , and curvature and torsion on Gamma and torsion mutation values at the segmentation control points are calculated; S6, whether the Gamma meets the engineering constraint requirements or not is judged; S7, whether the line shapes of segmentation are constructed or not is judged; and S8, the space linear shape constructed according to the control point sequence P segmentation is output. According to the method for constructing the highway three-dimensional space linear shape byadopting the quartic Bezier curve segmentation, by giving the unified analytical expression of space curves between the segmentation control points, a highway three-dimensional space line satisfying requirements can be intuitively constructed according to the segmentation control points, and the analytic accuracy is high and the engineering practicability is good.

Description

technical field [0001] The invention relates to the field of road alignment design, in particular to a method for segmentally constructing a three-dimensional space alignment of a road by using a quartic Bezier curve. Background technique [0002] The work content of highway alignment design is to overcome the constraints of terrain, ground objects and other constraints in the route selection area to determine a space curve that can ensure the safe driving of automobiles. The precise analytical expression of this space curve is to be sought. As a highway alignment, the space curve needs to satisfy both the engineering constraints and the geometric continuity constraints of vehicle driving comfort and stability. When selecting a line, the space curve control point sequence P can be obtained within the spatial range of the line selection area according to the field conditions i , to control the direction of the route. Now the problem is, according to the sequence of control ...

AI Technical Summary

Problems solved by technology

The problem is that the spatial alignment obtained by the two-dimensional split design will show the phenomenon of spatial geometric continuity attenuation, which means that the road alignment obtained by the two-dimensional design has defects in the three-dimensional spatial geometric characteristics

Images