Neobotics Foundation Inc.
LiDAR empty scanNEORACER DOCS
NEORACER DOCS
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TROUBLESHOOTING / LIDAR

THE EMPTY LIDAR SCAN.

Either the scanner isn't running, the cable is loose, or something is physically blocking the spinning head. Three checks, in the order they bite most often.

~0 minutesCommon cause: driver not upVisible from SSH
// YOU SEE
rc.lidar.get_samples() returns a list of 720 zeros. Same answer from ros2 topic echo /scan.
// WHAT SHOULD HAPPEN
A scan that looks like real distances in centimetres, refreshed at 30 Hz. The full and sample layout are on the LiDAR hardware page.
01 / IS THE SCANNER EVEN RUNNING?

THE SPINNING HEAD.

The scanner's spinning head is the fastest read on the car. If it isn't moving, the driver isn't running. If it's moving and you still get zeros, the data path is broken further up.

bash
# 1. Is the teleop driver running?
ssh racecar@neoracer
racecar status              # shows running nodes + /dev/osrbot_* symlinks
ros2 topic list             # should include /scan

# 2. Can you reach the Lakibeam over the lidar subnet?
ping -c 3 192.168.8.2        # the sensor sits at .2, host at .1

# 3. If the ping fails, the USB-C lidar link is down.
ip a | grep 192.168.8        # there should be a usb* interface at .1
racecar setup networking     # rebuilds AP + Ethernet + lidar subnet

# 4. If the ping succeeds, restart the teleop launch.
racecar teleop               # bring the whole stack back up

# 5. Confirm the topic publishes again.
ros2 topic hz /scan          # the rate the Lakibeam is configured for
02 / THE THREE THAT ACTUALLY BREAK

LIKELY CAUSES.

01

Lakibeam unreachable

ping 192.168.8.2 fails.
The Lakibeam is a UDP sensor on its own subnet. If the host side (the usb* interface at 192.168.8.1) is down, the driver gets no packets and /scan stays empty. racecar setup networking re-lays the subnet.
ping 192.168.8.2
02

Loose USB-C connector

The link between the sensor and the carrier board.
The USB-C link is small and easy to vibrate loose after a hard crash. Reseat both ends, then re-run racecar teleop so the lakibeam1 node sees the sensor again.
reseat USB-C · racecar teleop
03

Something on the dome

A sticker, tape, or cable in the field of view.
The driver returns zeros for any sample that doesn't get a return inside its range gate. A piece of black tape across the scanner produces the same number as a dead unit, so a quick wipe of the dome and a clear spin path rule this one out fast.
dome clear · 360° free