False assesment for topics_quiz

Course Support ROS2 Basics in 5 Days Humble (Python)
1

When I submitted my files for assesment the first time, I had some issue with setup.py file. I fixed it and the assessment proceeded.

Second submission said that the robot did not move. but when i ran the package, the robot did move and it’s final position was in the required tolerance. I thought it was a bug… so, i submitted again.

Third submission said that I am not subscribed to /odom topic well. which again does not make sense because the robot is moving from home to pickup and then coming back to pickup.

please help! I only have 2 submissions left now

2

@kepitychiar82fc2591b962496f
Did you check the “what you can check” feedback from the grader? It’s possible to fail the grading even if your code works, if you did not name the files as specified.

Let me check the logs for you.

3

I checked everything including the name of the files. here is the feedback for my third submission -

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but weirdly I had passed this check on my second submission (scored 8/10) as described in my post.

btw, here is the part of script where i am initializing the odom subscriber -

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4

From the logs, I can see that you named your node /odom_bridge instead of topics_quiz_node

ros2 topic info /odom -v
Type: nav_msgs/msg/Odometry

Publisher count: 1

Node name: odom_bridge <--- THIS IS THE ISSUE
Node namespace: /
Topic type: nav_msgs/msg/Odometry
Endpoint type: PUBLISHER
GID: 01.0f.87.0a.43.00.97.2f.00.00.00.00.00.00.11.03.00.00.00.00.00.00.00.00
QoS profile:
  Reliability: RELIABLE
  History (Depth): UNKNOWN
  Durability: VOLATILE
  Lifespan: Infinite
  Deadline: Infinite
  Liveliness: AUTOMATIC
  Liveliness lease duration: Infinite

Subscription count: 0
5

I am confused.
here is image snippet of my code. I have not used ‘odom_bridge’ anywhere in the code.

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EDIT -
I ran your command and I got this -

user:~$ ros2 topic info /odom -v
Type: nav_msgs/msg/Odometry

Publisher count: 1

Node name: odom_bridge
Node namespace: /
Topic type: nav_msgs/msg/Odometry
Endpoint type: PUBLISHER
GID: 01.0f.87.0a.43.00.3d.e3.00.00.00.00.00.00.11.03.00.00.00.00.00.00.00.00
QoS profile:
  Reliability: RELIABLE
  History (Depth): UNKNOWN
  Durability: VOLATILE
  Lifespan: Infinite
  Deadline: Infinite
  Liveliness: AUTOMATIC
  Liveliness lease duration: Infinite

Subscription count: 1

Node name: topics_quiz_node
Node namespace: /
Topic type: nav_msgs/msg/Odometry
Endpoint type: SUBSCRIPTION
GID: 01.0f.48.74.9a.35.d9.0d.01.00.00.00.00.00.13.04.00.00.00.00.00.00.00.00
QoS profile:
  Reliability: RELIABLE
  History (Depth): UNKNOWN
  Durability: VOLATILE
  Lifespan: Infinite
  Deadline: Infinite
  Liveliness: AUTOMATIC
  Liveliness lease duration: Infinite
6

I fixed the issue and completed the assesment -

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image
image840×565 72.9 KB

7

Could you please let us know how you fixed it?

8

I had to reset the simulaiton world and all terminals. I also removed colcon cache and killed all ros2 processes.
started it all again and submitted my quiz.