eric1221bday's profile - activity

I believe the rosbag messages are ordered at the order the rosbag stores them in, which is to say the order in why the r

Yeah I’ve actually since then gonna ahead and implemented this exact idea, though in my case i made target container a U

So looking at the API here, it occurs to me that I'm not sure if the current API will allow for loading composable nodes

Composable LifeCycle Node Reading the demos and examples as well as the rclcpp source, it seems that currently the LifeC

Composable LifeCycle Node Reading the demos and examples as well as the rclcpp source, it seems that currently the LifeC

Hi everyone

I've been creating some subscriptions in ROS2 lately, and had a question regarding the callback signature of any subscription or service creation. In ROS1, the callback signature of any message type could've been any one of the MsgType, MsgTypePtr, MsgTypeConstPtr, and additional const qualification and references of all of the previous. However as far as I can tell in ROS2, there seems to only be a limited subset of the above which would constitute a compilable callback signature.

To give a couple of examples in ROS2:

create_subscription<std_msgs::msg::String>(
  "/foo", 5, [this](std_msgs::msg::String::ConstSharedPtr msg)  // this works
create_subscription<std_msgs::msg::String>(
  "/foo", 5, [this](std_msgs::msg::String::UniquePtr msg)  // also works
create_subscription<std_msgs::msg::String>(
  "/foo", 5, [this](const std_msgs::msg::String::ConstSharedPtr msg)  // doesn't seem to work
create_subscription<std_msgs::msg::String>(
  "/foo", 5, [this](std_msgs::msg::String::ConstSharedPtr& msg)  // doesn't work either
create_subscription<std_msgs::msg::String>(
  "/foo", 5, [this](std_msgs::msg::String::ConstUniquePtr msg)  // neither does this

It seems that the internal templates do not allow some of these patterns. Is it possible with the current design to perhaps extend subscription callback signatures so that it can accept some of the above signatures?

Hey, thanks for the answer, interestingly I also saw a slightly different pattern today in one of the demo nodes here [

subscription callback types ROS1 vs. ROS2 Hi everyone I've been creating some subscriptions in ROS2 lately, and had a q

Thanks for the response. Since this would entail extending the current XML frontend tags, I'll have to put some more tho

Hi everyone

I've been looking through the new launch_ros xml/yaml frontend design and parsing recently, and noticed that there doesn't seem to be a way currently to launch composed nodes through this frontend? It looks as if the parser, when in python, uses the frontend to generate a Node, and thus not a ComposableNode let alone a ComposableNodeContainer.

Is there currently a plan to include launching composable nodes at all via the launch frontend? It seems quite important especially since there is a way to do so using the old ROS1 nodelet API.

EDIT: Some links to provide context

As an example, this is the current workflow for launch composition nodes using the launch_ros python interface.

Looking at the design of the roslaunch XML frontend. The only allowed tags which would launch a process would be executable and node.

In the node.py file in launch_ros, special provisions and imports were made to expose this action to the frontend, but it seems that currently the composable_node_container.py does not have any similar implementations.

Since this feature is not mentioned in either the design or the implementation, I wonder if this is something that the frontend is planned to support?

Launch Composed Nodes using the launch XML Frontend Hi everyone I've been looking through the new launch_ros xml/yaml f

compose launch Hi everyone I've been looking through the new launch_ros xml/yaml frontend design and parsing recently,

Launch Composed Nodes using the launch XML Frontend Hi everyone I've been looking through the new launch_ros xml/yaml f

Hi

I'm currently developing an autonomous MAV with the goal of achieving autonomous navigation and obstacle avoidance capability within an indoor environment. With an on board lidar and a downward facing camera using the google cartographer package I have been able to successfully localize the MAV as well as generate an updating 2D occupancy grid. Now the next step local navigation and path planning. From what I've read so far however, the ROS navigation stack, as well the vast majority of path planning and navigation packages out there assume an already generated map for navigation. In my case however I would require that the path planner be able to respond to map changes as well as perform some obstacle avoidance based on the current lidar reading. Are there currently any ROS packages that can accomplish this?

Failing that, are there any literature on path planning on dynamic map coupled with SLAM, so that I may implement it?

Currently the environment is assumed to be hallway like, so a 2D navigation algorithm would suffice.

Alright So I feel confident in answering this now that I've figured out the problem. This behavior is actually a very n