map doesn't work

[Marouan-22]

Hi,

I use rplidar A1 to scan, i do get the laser but it doesn't show anything if I set it on map? do you have any idea?

greetings!

[Kathan-k10]

same problem , any solution or other way to work on SLAM?

[ch1y1z1]

same problem , any solution or other way to work on SLAM?

[anasderkaoui]

Make sure you have the right transform tree in the lidar code. The error message on the terminal indicates that the issue is likely related to the transform tree which should look like this (if you run: ros2 run tf2_tools view_frames.py):
odom -> base_link -> laser
In some cases the message might also indicate that the queue size is full, so it has to be modified in the code to be larger.

[ayanami-rei00]

I had the same problem, my solution was to change "laser" to "laser_frame" in the TF transformation, and the problem was solved.

The overall running structure is as follows:

1. run radar and let it publish information through /scan topic
2. publish TF coordinate transformation and open rviz
3. start gmapping to build the map

The problem is that the queue size is not enough, but in fact, it is not successful in building TF transformation, which leads to the inability to find the relationship between the map and laser, and unable to correctly process the received data, which leads to the queue overflow, so simply expand the queue.The queue overflowed, so simply expanding the queue length cannot actually solve the problem.You can refer to my method to check if the TF tree is successfully built.