Issues with SLAM map creation in Unit 2

Course Support Robot Localization With Sensor Data
1

When trying to visualize the map to be built in RVIZ, it only says “No map recieved”.

In the terminal where I am starting the “roslaunch my_sumit_xl_tools start_mapping.launch” there is the following warning:

[ WARN] [1580224941.677455588, 407.400000000]: MessageFilter [target=odom ]: Dropped 100.00% of messages so far. Please turn the [ros.gmapping.message_notifier] rosconsole logger to DEBUG for more information.

I reckon there are some naming issues, as the instructions propose to call the package sumit…xxx instead of summit…xxx.

2

Finally after hours I have found the issue in the wrong instructions.

The following change needs to made to the start_mapping.launch

  <param name="base_frame" value="summit_xl_a_base_footprint"/>
  <param name="odom_frame" value="summit_xl_a_odom"/>

Furthermore, to control the vehicle in RVIZ, the output topic needs to be changed to:
/summit_xl_control/cmd_vel

1 Like
3

Hello @A07922101,

You are totally right. We have updated the Summit XL simulation recently and some topics and frames have been changed, producing this kind of issues in some Courses. I have updated the notebook accordingly to your comments. Let me apology for the inconvenience and please do not hesitate to let us know any other issues you find while doing the course.

Best,

4

Seriously? I am paying a lot of money and I did expect some kind of quality of this course. So far I did not learn much at all. I only wasted lots of times to find mistakes in your course. I am very unsatisfied! Would not have gotten myself this expensive abonnement if I had knew this before :frowning:

5

Hi Chris,
you are right, you do not deserve such kind of service. I personally apologize for it. It was completely on our side all those errors. We are putting remedy so this doesn’t happen anymore, but the harm has been already done to you. I am very sorry.

Please let me know if you would like us to cancel your subscription right now and we will fully refund your payment.

6

Thank you for the quick response. Please opt me out and refund the subscription.

7

Done. Let me know if you need something else from us.