lookahead distance in pure_pursuit should depend more parameters

[brkay54]

Checklist

• I've read the contribution guidelines.
• I've searched other issues and no duplicate issues were found.
• I've agreed with the maintainers that I can plan this task.

Description

In current implementation of Autoware Universe, lookahead distance in pure_pursuit just depend the velocity. This causes unwanted behaviors. For example, if lookahead_distance_ratio is low, when lateral error high in beginning (think that vehicle in side of road), vehicle enters the road with high heading error. If you increase the lookahead_distance_ratio to smoother entrance to road, It causes increasing lateral error in high curvature part of road.

Purpose

To avoid this, lookahead_distance should depend more variables (like lateral error and curvature of road). This will make the pure_pursuit more tunable.

Possible approaches

lookahead_distance = lookahead_distance_ratio * velocity + lateral_error_ratio * lateral_error - curvature_ratio * curvature

If there is high lateral error in curvature, you can increase the curvature_ratio, If vehicle enters the road with high heading error, you can increase the lateral_error_ratio for smooth entrance to road.

Definition of done

Proposed approach tested in real vehicle tests, worked well.