[cooperative perception] Track update in multiple object tracer node has no effect

[adamlm]

Summary

The track update stage of the multiple object tracker node's pipeline:

const mot::HasAssociation has_association{associations};
for (auto & track : track_manager_.get_all_tracks()) {
  if (has_association(track)) {
    const auto detection_uuids{associations.at(get_uuid(track))};
    const auto first_detection{detection_map[detection_uuids.at(0)]};
    track = std::visit(mot::covariance_intersection_visitor, track, first_detection);
  }
}

Has no effect because the get_all_tracks() function returns by value. There does not appear to be any functionality that lets a user modify a track_manager_'s track.

Commit

develop

Expected Behavior

The track updates in the pipeline persist across pipeline executions

Actual Behavior

The track updates have no effect because the track_manager_ does not have a way to update track states.

Steps to Reproduce the Actual Behavior

1. Observe code in multiple_object_tracker_component.cpp
2. Observe interface for multiple_object_tracking::FixedThresholdTrackManager

Related Work

CDAR-595

[MishkaMN]

Resolved with above PR