Method for fitting path points by improved cubic spline interpolation curves

Abstract

The invention discloses a method for fitting path points by improved cubic spline interpolation curves. The method for fitting the path points by the improved cubic spline interpolation curves comprises the steps that step 1, a path composed of the discrete path points is obtained through a graph search algorithm; step 2, every two adjacent path points are subjected to interpolation by using an improved cubic spline interpolation curve method, and high-density continuous path points are obtained; and step 3, the high-density path points formed by interpolation obtained by the cubic spline interpolation curves are sequentially connected to generate a path. According to the method for fitting the path points by the improved cubic spline interpolation curves, through the steps 1-3, the effectof fitting the path points can be effectively achieved by using a spline interpolation method.

Description

technical field [0001] The invention relates to the technical field of route planning for intelligent vehicles, and more specifically relates to an improved cubic spline interpolation curve fitting method for route points. Background technique [0002] Because of its potential to improve road traffic safety, economy, and travel convenience, smart cars are attracting more and more attention. The path planning of intelligent vehicles is the key point of decision-making neighborhood research, which is responsible for planning a safe and feasible driving path for intelligent vehicles. Under the condition of satisfying non-holonomic constraints, in the configuration space containing obstacle information and drivable space, a series of discrete path points can be obtained through the path planning algorithm. These path points satisfy the vehicle kinematics constraints and have no collision requirements. How to obtain a continuous path that satisfies the non-holonomic constraints...

AI Technical Summary

Problems solved by technology

Although the curve path generated by the B-spline curve fitting method can guarantee the smoothness of the curve, each path point does not contain angle information, and cannot guarantee to meet the maximum steering angle constraint of vehicle kinematics; Calculate the position of the path point inserted before and after the path point to meet the angle requirements of the path point, but the amount of calculation for path point insertion before and after each path point is large; for the traditional cubic spline interpolation curve method, when two path points are in the horizontal direction In the case of too close in the direction of the vertical axis or the vertical axis, and the independent variable changes in the opposite direction, the curve path fitted by the traditional cubic spline curve will appear arbitrarily large shock distortion (also known as "Runge phenomenon"), The phenomenon that the first derivative of two adjacent curves is discontinuous at the junction, resulting in the generated curve path not satisfying the drivability of the vehicle

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