I’m sorry. I thought that object in front of ROSbot on your screenshot was “STOP” sign (on the screenshot we see only the back side of the object).
In that case, the problem can be caused by:
- Update of some pkg included in project
- More object in playground (like you suggested) it may not have been tested with an object of a similar shape
- Not enough computing power
Because of project is no longer support in two first cases, the only solution is to use debugging tools to check where the problem is located.
In the last case, it will be enough to open
htop and monitor computing powers consumption after start launch file.
Please let me know as soon as you will find something.