Lidar sensor returns all inf

Ask
1

Hi team,

I found out that topic /scan returns all inf for ranges and all zeros for intensities. I wonder if it means the lidar sensor doesn’t open correctly or breaks.

Best,
Ruinian Xu

2

Hey @gtsimonxu, would you run through the suggestions in this thread and let us know what the sensor returns?

3

Hi @bshah , the following is what I got by running three commands. It seems look like normal?

stretch_rp_lidar_jog.py --reset
For use with S T R E T C H (R) RESEARCH EDITION from Hello Robot Inc.
---------------------------------------------------------------------

[INFO] [rplidar]: Reseting the sensor
None
[INFO] [rplidar]: Stoping motor

stretch_rp_lidar_jog.py --motor_on
For use with S T R E T C H (R) RESEARCH EDITION from Hello Robot Inc.
---------------------------------------------------------------------

[INFO] [rplidar]: Starting motor

stretch_rp_lidar_jog.py --health
For use with S T R E T C H (R) RESEARCH EDITION from Hello Robot Inc.
---------------------------------------------------------------------

[INFO] [rplidar]: Asking for health
('Good', 0)
[INFO] [rplidar]: Stoping motor
4

Great, thanks! And what do you get when you try the fourth command: stretch_rp_lidar_jog.py --range

5

Hi @bshah
I am not sure if I just didn’t wait for the enough time but after running the command, it was stuck there. I also noticed that there was a yellow light by looking through the gap between base shell and lidar.

stretch_rp_lidar_jog.py --range
For use with S T R E T C H (R) RESEARCH EDITION from Hello Robot Inc.
---------------------------------------------------------------------

[INFO] [rplidar]: Starting motor
[INFO] [rplidar]: Asking for health
[INFO] [rplidar]: starting scan process in normal mode
6

Thanks @gtsimonxu, that aligns with what I suspected. One last test we can run is launching the same command, and when it gets stuck, try spinning the lidar by hand a couple times. It should return data once the sensor has been spun by hand.

If so, the motor in the Lidar has died. We can send you a replacement it you reach out to support@hello-robot.com. We’ve designed the lidar module to be easily replaced in your robot.

7

Hi @bshah
I don’t think the motor has died since the Lidar is spinning. I use my hand to spin the lidar (even though it was spinning) but got nothing in the terminal.

8

Hmm that’s odd. If you’re able to jump on a debugging call, would you reach out to support@hello-robot.com so we can schedule a video call?

9

Hi @bshah sure, I just sent out an email to support@hello-robot.com. Thank you so much for your help!

1 Like