Trajectory Concatenator

Purpose/Role

This node aggregates trajectory candidates from multiple trajectory generators into a single autoware_internal_planning_msgs/msg/CandidateTrajectories message. It is intended to be placed between trajectory generators and the selector/ranker.

Algorithm Overview

When a CandidateTrajectories message is received (from either ~/input/trajectories_generative or ~/input/trajectories_backup), the library splits it by generator_id and updates an in-memory buffer so that only the most recent trajectory set for each generator is retained.

A 100 ms timer then scans this buffer and drops any entry whose header stamp is older than the configured duration_time. Immediately after pruning, the timer concatenates all remaining trajectories and their accompanying generator_info arrays, publishes the aggregated message.

Interface

Topics

Direction	Topic name	Message Type	Description
Subscriber	~/input/trajectories_generative	autoware_internal_planning_msgs/msg/CandidateTrajectories	Trajectory sets from generative planners
Subscriber	~/input/trajectories_backup	autoware_internal_planning_msgs/msg/CandidateTrajectories	Trajectory sets from backup planners
Publisher	~/output/trajectories	autoware_internal_planning_msgs/msg/CandidateTrajectories	Concatenated list of all buffered trajectories

Parameters

Name	Type	Description	Default	Range
duration_time	float	Duration time to keep the trajectory (it will be deleted once exceeding this value)	0.2	≥0.0