resetOdometry as a ros2 srv

[Fixit-Davide]

Is your feature request related to a problem? Please describe.
During debugging or testing session it could be useful to reset to odometry of a moving robot by simply calling a ROS2 service.

Describe the solution you'd like
A simple ROS2 service (std_srvs/srv/Empty or std_srvs/srv/Trigger) that, once triggered, calls for the method resetOdometry() of the implemented controller.

[alireza-moayyedi]

Hello,

Is there an update on this issue? It would be really useful to be able to reset the odometry. My own usecase for instance is when the robot has different operating modes i.e., with and without diff drive engaged. So I want to be able to reset odometry whenever diff drive is engaged.

I see that the underlying function already exists:

https://github.com/ros-controls/ros2_controllers/blob/master/diff_drive_controller/src/diff_drive_controller.cpp#L600

So a simple ROS2 api like a topic or service should be enough to have this feature.

I see that there was a similar issue for ROS1 (ros-controls/ros_controllers#564) where this functionality was appreciated. There, @bmagyar mentioned that a topic would be more preferable (due to potential blocking) which makes sense to me. But I leave that up to you.

[christophfroehlich]

In ros2_control, we already have a different thread which will process the service call.

We already have a controller having implemented this as a service

ros2_controllers/tricycle_controller/src/tricycle_controller.cpp

Lines 348 to 352 in d1844e6

	// Create odom reset service
	reset_odom_service_ = get_node()->create_service<std_srvs::srv::Empty>(
	DEFAULT_RESET_ODOM_SERVICE, std::bind(
	&TricycleController::reset_odometry, this, std::placeholders::_1,
	std::placeholders::_2, std::placeholders::_3));

But I see a problem that we don't have a thread-save implementation there to exchange data with the realtime loop. See the pid_controller, where we use a RealtimeBuffer for that (a RealtimeBox would be better suited for that, or just use an (by default) atomic bool value for do_reset).

ros2_controllers/pid_controller/src/pid_controller.cpp

Lines 241 to 255 in d1844e6

	auto set_feedforward_control_callback =
	[&](
	const std::shared_ptr<ControllerModeSrvType::Request> request,
	std::shared_ptr<ControllerModeSrvType::Response> response)
	{
	if (request->data)
	{
	control_mode_.writeFromNonRT(feedforward_mode_type::ON);
	}
	else
	{
	control_mode_.writeFromNonRT(feedforward_mode_type::OFF);
	}
	response->success = true;
	};

Do you want to take this and implement this properly in all mobile robot controllers?

[github-actions]

This issue is being labeled as stale because it has been open 45 days with no activity. It will be automatically closed after another 45 days without follow-ups.