feat(lane_changing): improve computation of lane changing acceleration

[mkquda]

Description

Currently when generating candidate lane change paths, we sample multiple longitudinal acceleration values, however for values below 0.0 (decelerating), it is only applied to the prepare phase, while min acceleration for lane changing phase is limited to 0.0, meaning we assume no deceleration during lane changing phase. And this behavior is not configurable.

Sometimes this assumption can result in not finding a safe candidate path near the terminal, specifically when there is a leading target lane object.

It is better to allow some deceleration during lane changing phase when approaching terminal to increase the chances of finding a safe candidate path.

Changes

Modified function calc_lane_changing_acceleration:

• IF sampled longitudinal acceleration is negative, AND ego is near terminal, THEN return a ratio of sampled longitudinal acceleration determined by parameter lane_changing_decel_factor
• IF sampled longitudinal acceleration is negative, AND ego is NOT near terminal, THEN return 0.0 (same as before)

Related links

Parent Issue:

• Link

How was this PR tested?

• PSIM
• TIER IV Internal Evaluation

Notes for reviewers

None.

Interface changes

None.

ROS Parameter Changes

Additions and removals

Change type	Parameter Name	Type	Default Value	Description
Added	lane_changing_decel_factor	double	0.5	longitudinal deceleration factor during lane changing phase

Effects on system behavior

Increase chances of finding a safe candidate path near terminal when there is a leading target lane object.

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 62.50000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 29.50%. Comparing base (959e57b) to head (e77d6bf).
Report is 11 commits behind head on main.

Files with missing lines	Patch %	Lines
..._path_lane_change_module/src/utils/calculation.cpp	25.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9545      +/-   ##
==========================================
- Coverage   29.50%   29.50%   -0.01%     
==========================================
  Files        1444     1446       +2     
  Lines      108519   108554      +35     
  Branches    41396    41401       +5     
==========================================
+ Hits        32022    32029       +7     
- Misses      73377    73407      +30     
+ Partials     3120     3118       -2     

Flag	Coverage Δ		*Carryforward flag
differential	22.13% <62.50%> (?)
total	29.50% <ø> (-0.01%)	⬇️	Carriedforward from cca0655

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[github-actions]

Documentation URL: https://autowarefoundation.github.io/autoware.universe/pr-9545/
Modified URLs:

• https://autowarefoundation.github.io/autoware.universe/pr-9545/planning/behavior_path_planner/autoware_behavior_path_lane_change_module/