Discussion - SLAM on our robot with slam_toolbox (Making a Mobile Robot Pt 15)

Hi did you ever solve this issue? I am currently facing this problem and I am looking for a solution.

Did you every figure out the answer to this problem?

Hi, I want to run SLAM on robot only have two motor without encoders. me no odometry so how i can run SLAM on my robot. what type of changes i need to made in slamtoolbox having no odometry just rplidar ?

Hi Josh. First of all thank you for the tutorials they have been a great introduction to using ROS. I seem to have a problem with loading the slam map in rviz, itdoesn’t show up at all. Under Map, Message it says No map recieved and under Transfor it ays could not transform from [] to [map]. I have tried everything, from checking the publishing of the topics /map, /map to /odom, also the tf tree looks correct. I do not know what the problem may be. Thanks in advance.

did it solved? i also got this error

Hey Josh and everybody,
I don’t know if you ever read this or not :sweat_smile: but first thank you for the nice content. And second, I have 2 problems. I have searched for days and checked many underlying things, but couldn’t realize the solution.

  1. When I run the robot around, the whole map (obstacles detected by Lidar) turns around. It seems like the speed of the robot in Rviz is simply twice as in Gazebo. Later I realized that in Rviz, the odom frame and map frame are stuck together. And I think this might be the reason (?). I have followed your tutorial and I don’t know how to solve it.

  2. When I add the map topic in Rviz, I get a status warning, saying ā€œNo map receivedā€. When I echo the /map topic, nothing shows up. I don’t know why this topic is not being published.

@JoshNewans Your help, is much is greatly appreciated.

Anyone who can help is appreciated as well :slight_smile:

@JoshNewans

Hello

I’ve been trying to put together what your video says with the official rplidar repository (GitHub - Slamtec/rplidar_ros), but I’ve had a problem when trying to run Slam_toolbox, this because when I try to generate a map I keep getting that there is no map itself.

I want to make SLAM to be able to register a track in real time, that’s why I never tried anything with gazebo or anything like that, however, I don’t know how to fix the problem.

The codes I’m using to start things up are as follows:

Start lidar (once I run slam_toolbox it doesn’t generate me map):

"sudo chmod 666 /dev/ttyUSB0 

source install/setup.bash

ros2 launch rplidar_ros view_rplidar_a1_lauch.py"

Run map (it generates the folders but I don’t get the lidar):

ros2 run rviz2 rviz2 -d /opt/ros/humble/share/nav2_bringup/rviz/nav2_default_view.rviz

I’m getting this issue with my robot. I’m not using a RPLidar though. My Lidar model is Litra-LTME02

Litra LTME02

Please take a look at the image

https://imgur.com/a/ZyBfe6P

@JoshNewans

I’m getting this error while running the slam_toolbox
[WARN] [1722247013.037882215] [slam_toolbox]: Failed to compute odom pose

and also this warning in rviz2
Warning: TF_OLD_DATA ignoring data from the past for frame right_wheel at time 8.194000 according to authority Authority undetectable

How do I resolve this?
Thanks in advance!

I have a problem with SLAM. Everything works fine, but after some time, the map suddenly rotates by 80 degrees. This might be because I’m using cingulum tracks and simulating them with a single central wheel. Sometimes, I notice that when the robot makes a 360-degree turn in the real world, it either makes a 360-degree turn in RViz, or, other times, the 360-degree turn in the real world is shown as a 400-degree turn in RViz.

I cant express how grateful I am. Tried everything I can and only this helped solve my problem.

Did anyone figure out how to solve the discrepancy between real robot and odom velocity? I’m running in open loop mode so my map sometimes gets messed up due to this…

Hey there, did anyone else have an issue that their robot motors perform slightly different, I think this is messing up the SLAM

One motor seems to rotate more than the other

I have a problem, I running with humble in WSL of window. Please help!
jsonbk@PCE-0163-LE-N:~/dev_ws$ rviz2 -d src/my_bot/config/main.rviz
QStandardPaths: wrong permissions on runtime directory /run/user/1000/, 0755 instead of 0700
[INFO] [1739853979.875756336] [rviz2]: Stereo is NOT SUPPORTED
[INFO] [1739853979.875846857] [rviz2]: OpenGl version: 4.1 (GLSL 4.1)
[INFO] [1739853979.904782952] [rviz2]: Stereo is NOT SUPPORTED
[INFO] [1739853980.056907971] [rviz2]: Stereo is NOT SUPPORTED
[INFO] [1739853984.240293902] [rviz2]: Trying to create a map of size 145 x 151 using 1 swatches
[ERROR] [1739853984.266594317] [rviz2]: Vertex Program:rviz/glsl120/indexed_8bit_image.vert Fragment Program:rviz/glsl120/indexed_8bit_image.frag GLSL link result :
active samplers with a different type refer to the same texture image unit

hi. were you able to solve this issue?

Continuing the discussion from Discussion - Nav2 Introduction (Making a Mobile Robot Pt 16):

hi , I m really in need of help in navigation, the map creation using slam is perfect but when i try to navigate by giving the goal i m getting exploartion errors, Behavior Tree tick rate,etc and not moving an inch .Every other terminal seems to be working fine except the nav2 terminal

[bt_navigator-5] [INFO] [1743701696.297607268] [bt_navigator]: Begin navigating from current location (-2.62, -0.08) to (-1.36, 0.01)
[planner_server-3] [ERROR] [1743701696.761987230] [transformPoseInTargetFrame]: Extrapolation Error looking up target frame: Lookup would require extrapolation into the future. Requested time 1743701696.294112 but the latest data is at time 844.250000, when looking up transform from frame [odom] to frame [map]
[planner_server-3]
[planner_server-3] [WARN] [1743701696.762257369] [planner_server]: Could not transform the start or goal pose in the costmap frame
[planner_server-3] [WARN] [1743701696.762371245] [planner_server]: [compute_path_to_pose] [ActionServer] Aborting handle.
[planner_server-3] [INFO] [1743701696.782962024] [global_costmap.global_costmap]: Received request to clear entirely the global_costmap
[planner_server-3] [ERROR] [1743701697.872118599] [transformPoseInTargetFrame]: Extrapolation Error looking up target frame: Lookup would require extrapolation into the future. Requested time 1743701696.294112 but the latest data is at time 845.050000, when looking up transform from frame [odom] to frame [map]
[planner_server-3]
[planner_server-3] [WARN] [1743701697.874073618] [planner_server]: Could not transform the start or goal pose in the costmap frame
[planner_server-3] [WARN] [1743701697.874485703] [planner_server]: [compute_path_to_pose] [ActionServer] Aborting handle.
[controller_server-1] [INFO] [1743701697.888284498] [local_costmap.local_costmap]: Received request to clear entirely the local_costmap
[planner_server-3] [INFO] [1743701697.890384788] [global_costmap.global_costmap]: Received request to clear entirely the global_costmap
[bt_navigator-5] [WARN] [1743701698.799354508] [BehaviorTreeEngine]: Behavior Tree tick rate 100.00 was exceeded!

The errors still goes…

amod@amod:~$ ros2 topic info /scan --verbose
Type: sensor_msgs/msg/LaserScan

Publisher count: 1

Node name: laser_controller
Node namespace: /
Topic type: sensor_msgs/msg/LaserScan
Endpoint type: PUBLISHER
GID: 01.0f.86.6d.c6.58.cc.7e.00.00.00.00.00.00.57.03.00.00.00.00.00.00.00.00
QoS profile:
Reliability: RELIABLE
History (Depth): UNKNOWN
Durability: VOLATILE
Lifespan: Infinite
Deadline: Infinite
Liveliness: AUTOMATIC
Liveliness lease duration: Infinite

Subscription count: 1

Node name: slam_toolbox
Node namespace: /
Topic type: sensor_msgs/msg/LaserScan
Endpoint type: SUBSCRIPTION
GID: 01.0f.86.6d.09.5a.4c.5b.00.00.01.00.00.00.24.04.00.00.00.00.00.00.00.00
QoS profile:
Reliability: BEST_EFFORT
History (Depth): UNKNOWN
Durability: VOLATILE
Lifespan: Infinite
Deadline: Infinite
Liveliness: AUTOMATIC
Liveliness lease duration: Infinite

How can I change this QoS profile of LaserScan to Best Effort?

Has anyone done this please revert.