Add a Custom Smoother

The following steps are necessary to add a new post-smoothing or path improvement algorithm to Bench-MR.

Your implementation needs to provide an OMPL-compatible function that modifies a ompl::geometric::PathGeometric& reference inplace.

Register Smoother in PlanningSettings

Register your smoother as a new entry in global::settings.benchmark.smoothing in base/PlannerSettings.h to allow the benchmark configuration to enable the use of this smoother. Each entry follows the same format:

Property<bool> smoother{true, "smoother", this};

where smoother is the name of your smoother.

Add Smoother to Benchmark Function

To execute the smoother when its corresponding flag in PlanningSettings is active, we need to add the following condition to the evaluateSmoothers function in utils/PathEvaluation.hpp:

if (global::settings.benchmark.smoothing.<smoother>) {
  ompl::geometric::PathGeometric path(planner->solution());
  // TODO: evaluate your smoother here by modifying `path` inplace
  PathStatistics path_stats;
  evaluate(path_stats, path, planner);
  j["<smoother>"] = {
      {"time", /* TODO: insert elapsed time for smoothing */},
      {"collision_time",
       global::settings.environment->elapsedCollisionTime()},
      {"steering_time", global::settings.ompl.steering_timer.elapsed()},
      {"name", "<smoother name>"},
      {"cost", path.length()},
      {"trajectory", Log::serializeTrajectory(path)},
      {"path", Log::serializeTrajectory(path, false)},
      {"stats", nlohmann::json(path_stats)["stats"]},
      // add any additional smoother stats / properties you would like to log
  };
}

where <smoother> is the name of your smoother.

Update Front-end Definitions

Go to python/definitions.py to optionally register a user-friendly title in the smoother_names dictionary that is displayed in the plots inplace of the smoother name.

smoother_names = {
	# ...
	'<smoother>': 'Desired title used in plots'
}

After compiling the benchmark executable, the new smoother is now available from MPB, e.g. via the MPB.set_smoothers(["<smoother>"]) helper function.