ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question
2

How to specify costmap_2d layers?

asked 2016-12-30 18:10:23 -0600

epsilonjon gravatar image

updated 2016-12-30 18:13:13 -0600

Hi.

I am trying to define an obstacle layer in my costmap_common_params.yaml file. As per the tutorial here, this is what I have for my layers:

static:
  map_topic: /map
  first_map_only: true

inflation:
  inflation_radius: 0.1

obstacles:
  observation_sources: rtabmap
  rtabmap: {sensor_frame: /kinect_frame_optical, data_type: PointCloud2, topic: /rtabmap/cloud_map, marking: true, clearing: true}

My local_costmap_params.yaml is then

global_frame: odom
rolling_window: true

plugins:
  - {name: obstacles, type: "costmap_2d::ObstacleLayer"}
  - {name: inflation, type: "costmap_2d::InflationLayer"}

Unfortunately when I start move_base, I get the message

[ INFO] [1483141055.544545392, 135.629000000]: Using plugin "static"
[ INFO] [1483141055.767972141, 135.725000000]: Requesting the map...
[ INFO] [1483141056.074817270, 135.945000000]: Resizing costmap to 2318 X 2368 at 0.005000 m/pix
[ INFO] [1483141056.166230343, 135.976000000]: Shutting down the map subscriber. first_map_only flag is on
[ INFO] [1483141056.248844376, 136.030000000]: Received a 2318 X 2368 map at 0.005000 m/pix
[ INFO] [1483141056.276602131, 136.052000000]: Using plugin "inflation"
[ INFO] [1483140087.785485118, 121.036000000]: Using plugin "obstacles"
[ INFO] [1483140087.988274092, 121.200000000]:     Subscribed to Topics: rtabmap

followed some time later by lots of

[ WARN] [1483141579.312730659, 306.346000000]: Request for map failed; trying again...
[ WARN] [1483141581.391496974, 306.847000000]: Request for map failed; trying again...
[ WARN] [1483141583.448695892, 307.347000000]: Request for map failed; trying again...
[ WARN] [1483141584.839228073, 307.848000000]: Request for map failed; trying again...
[ WARN] [1483141586.776772495, 308.348000000]: Request for map failed; trying again...

I assume these errors are due to the obstacles layer, since it has received the static map, and I have first_map_only set to true?

Primarily I cannot understand why move_base is telling me that it is subscribing to topic rtabmap instead of /rtabmap/cloud_map like I specified in my config file. It seems like it is not linking the observation source with its specification, and so is using the default topic (which would be rtabmap according to the documentation).

If I change the obstacles layer in my costmap config to

obstacles:
  observation_sources: "/rtabmap/cloud_map"
  "/rtabmap/cloud_map": {sensor_frame: /kinect_frame_optical, data_type: PointCloud2, topic: /rtabmap/cloud_map, marking: true, clearing: true}

then I do get

[ INFO] [1483140087.785485118, 121.036000000]: Using plugin "obstacles"
[ INFO] [1483140087.988274092, 121.200000000]:     Subscribed to Topics: /rtabmap/cloud_map

and rqt_graph shows that rtabmap is publishing /rtabmap/cloud_map to move_base. However, I still get the "Request for map failed; trying again..." errors, and the local_costmap doesn't seem to update in rviz.

If someone could help me with this I'd be very grateful. It's been driving me mad for hours now!

Thanks.

edit retag flag offensive close merge delete

Comments

Seems like it prints the name of the source, not the topic name:

/move_base:     Subscribed to Topics: laser_scan_sensor
Humpelstilzchen gravatar image Humpelstilzchen  ( 2017-01-02 03:31:40 -0600 )edit

4 Answers

Sort by ยป oldest newest most voted
3

answered 2017-01-06 12:19:30 -0600

clyde gravatar image

The message "Subscribed to Topics" is somewhat misleading... it should probably say "Subscribed to sources" since it's echoing the "observation_sources" parameter. Here's the code:

  // get the topics that we'll subscribe to from the parameter server
  nh.param("observation_sources", topics_string, std::string(""));
  ROS_INFO("    Subscribed to Topics: %s", topics_string.c_str());

Further down you'll see that it's actually subscribing to the topic you specified. If you turn on debug you'll see the message:

ROS_DEBUG("Creating an observation buffer for source %s, topic %s, frame %s", source.c_str(), topic.c_str(),
          sensor_frame.c_str());

As for the message "Request for map failed; trying again..." -- David Lu is correct, that message is coming from amcl.

edit flag offensive delete link more
2

answered 2017-01-04 13:21:44 -0600

billy gravatar image

I think you need to you the static map plugin as well. Something like this.

plugins:
  - {name: static_map, type: "costmap_2d::StaticLayer"}
  - {name: obstacles, type: "costmap_2d::VoxelLayer"}
  - {name: inflation_layer, type: "costmap_2d::InflationLayer"}
edit flag offensive delete link more

Comments

I have the static map plugin in my global costmap yaml file. Sorry, should have indicated this, apologies fort he confusion.

epsilonjon gravatar image epsilonjon  ( 2017-01-07 05:27:12 -0600 )edit
2

answered 2017-01-04 18:19:14 -0600

matlabbe gravatar image

updated 2017-01-04 18:21:03 -0600

Hi,

You should not use /rtabmap/cloud_map in obstacle layer, use kinect's output cloud directly for the local costmap (well the point cloud sent by the sensor if not a kinect, you can also use a Voxel filter to downsample the point cloud and a passthrough filter to remove the floor so that all points can "mark" and "clear"). Your obstacle frame would be base_footprint or base_link.

Use RVIZ to debug your costmaps. For example, show the occupancy grid /map that you are subscribed to with the global costmap to see if they match.

cheers

edit flag offensive delete link more

Comments

1

Thanks for the tip, I will change this.

epsilonjon gravatar image epsilonjon  ( 2017-01-07 05:30:11 -0600 )edit
1

answered 2017-01-04 10:31:53 -0600

David Lu gravatar image

It looks to me like the "Request for map" error is coming from the amcl node. Is it successfully connected in the ros graph?

edit flag offensive delete link more

Question Tools

3 followers

Stats

Asked: 2016-12-30 18:10:23 -0600

Seen: 3,500 times

Last updated: Jan 06 '17