Flickering visualization results

yiwei

Hi all, I'm working with a os1-64 lidar, with 1.13 firmware. I'm getting a wired flickering visualization result from the ROS driver provided by ouster. I thought it's the rviz problem. But it seems the same when using ouster studio. I do notice that this only happens when the lidar is running at 20 hz, 10 hz seems fine to me. I wonder do many users have the same experience?

SlavaPavlov

Dear @yiwei,
Let’s start by going through the steps listed below.

Use the latest and greatest software/firmware:
- ROS Drivers
- FW 1.14-beta.12
Reset the configuration of the sensor through the sensor’s webpage
Configure the sensor how you normally would, ie:
- nc into the sensor (for example)
- get_config_param active udp_ip should show ““.
- set_config_param udp_ip 10.5.5.3 ← or what you configured your interface to be
- set_config_param lidar_mode 1024x20 ← or which lidar mode you want to start with
- reinitialize
- write_config_txt ← if you power cycle these parameters above will remain
- get_config_param active lidar_mode should return 1024x20
- exit the nc prompt
ROS setup:
- Execute sudo apt-get install libglfw3-dev libtclap-dev libglew-dev
- Execute export CMAKE_PREFIX_PATH=/path/to/ouster_example
- Execute source /opt/ros/[kinetic_or_melodic]/setup.bash
- Execute mkdir -p workspace/src && cd workspace && ln -s /path/to/ouster_example ./src/ && catkin_make -DCMAKE_BUILD_TYPE=Release to build your own ROS workspace
- Then, execute source /path/to/workspace/devel/setup.bash
- Go to the ouster_ros dir in path/to/workspace/src/ouster_example and run roslaunch ouster.launch sensor_hostname:=<sensor_ip> udp_dest:=<dest_ip> lidar_mode:=<mode_of_choice> ← in this case try 1024x20.

You should also be on Gigabit ethernet. I hope this resolves the issue!

dllu

Don't use firmware 1.14 with gen 1 sensors. It is only for gen 2 sensors.

But flickering is often due to a problem with the ethernet connection so make sure to use a better ethernet cable and ethernet adapter.

yiwei

dllu Thanks for telling me, I was thinking that maybe the UDP buffer size, but it didn't work. I think will try find a better usb to ethernet adapter for my laptop.

SlavaPavlov

As @dllu stated correctly, the firmware 1.14 beta 12 is not backward compatible with OS1 gen1 sensors. Although firmware can be updated in gen1 sensors, the tests indicate certain issues and therefore it is not recommended to upgrade it in gen1 sensors.
Please refer here if you wish to upgrade the firmware.

yiwei

SlavaPavlov I also encountered some issue while cmake the 1.14 driver. It looks like the it doesn't find ouster_viz and ouster_client.

yiwei

So I tried a couple best quality ethernet cable and usb to ethernet adapter in my lab, it doesn't change so much. I'm not sure if I should call this flickering, so I include a video link to demonstrate.https://www.youtube.com/watch?v=CTfFr5K63iM&feature=youtu.be

KelvinKANG

I watched video link. I think, your ethernet connection is 100Mbps.
If ethernet link is 100Mbps, you can see phenomena such as video links.
In 1024x10 --> data rata 66 Mbps
in 1024x20 --> data rate 130Mbps

affi

Hey KelvinKANG and all others.

I am facing the same problem. In order to find the solution for the problem I have the posted the explanations here on Ouster example GitHub Repo and Ros answers forum.

There is another post here on the forum which I mentioned my problem statement. Might it help anyone to check and able to get what I am trying to achieve.

Any feedback would be appreciated.

Regards,
Affi