Following the tutorial here: https://www.youtube.com/watch?v=ndvwDFi-I3I, I have been trying to set up a multi-robot slam simulation using turtlebot 3. I am running ROS neotic on ubuntu 20.04.
Currently, I am getting the error "no map received" in rviz
shown here.
Some changes I have made are to add some static transform publishers, to multi_map_merge.launch to fix another error, "no transform from to map" and to edit the topic name of base_scan in turtlebot3_waffle.gazebo.xacro from scan to /scan to fix the "For frame [base_scan]: Frame [base_scan] does not exist", which removed the error from laser_scan in rviz.
the "no map received error" has been present in rviz with both the errors above and has not appeared since solving them.
here is my tf tree from tf view_frames, part1, part2.
The robot state publisher section is identical for all 3 robots and all are connected to base_footprint.
Here is my rqt graph as well.
From the above graphs, I think the problem lies with the /scan topic, in the rqt graph the scan topic for each robot is not receiving data from gazebo, when running slam for one robot the rqt graph, has gazebo publishing to /scan, and using rostopic info /scan is receiving data in my multi slam simulation however the "robotnamespace"/scan topics are not. however, I am new to ros and am unsure if this is the cause of the problem or not.
I am unsure how to proceed in fixing this error, and any help would be appreciated.
Related
I am trying an example for knowledge graph. When i run this command
:play https://guides.neo4j.com/nlp_knowledge_graphs
some querys will be present and i am running that. But when i run the command in 5th slide, I should get triplets loaded to be some thousands. I am getting 0 and termination status is also "KO" but it should be "OK".
In extraInfo i got error like this:-> "PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target"
Here is the github link.
When i am executing Software systems, Programming languages, Data formats I am getting same result as "KO" and 0.
Please help me here. I already imported APOC, Graph Data science Library and Neosemantics(n10s).
The result should be like this for Software systems.
I want to work on a surface vehicle in the gazebo environment. I've looked at various resources on this topic, but haven't been able to find a working example file for the system I'm using. In the sources I found, the vehicle sinks into the water. I also did research to get it on the water, but I couldn't get any results. My system information is as follows. Is there a source for my system information where I can work on the surface vehicle? Or do I need to change the version?
System info:
Ubuntu 20.04
ROS Noetic Distribution
Gazebo 11
I added ocean and boat model to Gazebo environment. To keep the boat afloat, I looked at this resource:
https://classic.gazebosim.org/tutorials?tut=hydrodynamics&cat=physics
I added the codes in this resource to the boat.sdf file. But the boat did not rise above the water.
I am using Watson Studio to build a Visual Recognition model for detecting farms in satellite images by using Object detection.
When I try to add labels (with add objects) to the pictures I have uploaded to the model the following error occurs:
An error occurred while updating farm_vb_1.png
Error in Watson Visual Recognition service: Received empty image data response.
My question is why I get this message and how I can fix it?
Thanks in advance.
I'm new at zynq board. I am trying to work with XADC of zynq-xc7z020 and want to see its quality for my application through vivado and xilinx SDK.
I tested two ways of designing through lab3 and lab4 tutorials. Synthesis, implementation and generating bitstream are OK in vivado. in the Xilinx SDK, after programming of the board, when I run a simple printf through system debugger or GDB but I get "AHB AP transaction Error". I googled it a lot and spent few days for it, but didn't get any solution. Additional, I tried to connect to the arm core of the board through XMD console by "connect arm hw" command. but console get JTAG connection error, while JTAG cable is connected and programming of the board is done.
suggested solutions of here didn't help.
thank you.
I understand what my mistake was.
Through XSCT console in SDK, I run mrd command to access DDR and read its address. but I couldn't. So I got that the problem was from DDR configurations.
I create a new project and at the first step of designing, after adding ZYNQ7 Processing System to block design, click on 'run block automation' and continue all previous steps and it worked. The point was that automation run. It sets some auto configuration of block that have to be set; and my mistake was this, that I connected DDR port manually.
i'm going to do the intrinsic calibration for my kinect camera, I've followed this tutorial http://wiki.ros.org/camera_calibration/Tutorials/MonocularCalibration
However, when I use command rostopic list, I just found 2 topics:
/rosout
/rosout_agg
but didn't find wanted topics that are:
/camera/camera_info
/camera/image_raw
I've installed camera_calibration package, and I'm using ROS Indigo.
In my case, I use a kinect and freenect driver for it, so the problem is I need to "roslaunch detection freenect.launch" first, then I can see my wanted topics that are /camera/rgb/image_color and camera:=/camera/rgb.