ModalAI Forum

@Alex-Kushleyev

Thanks for the explanation — I now understand how to use the TOF sensor.
I’ll use the ROS point cloud directly for my research.

Hi,
I’m using the Starling 2 Max with VOXL 2 and I’m trying to access depth information from the onboard TOF sensor.

I am subscribing to /tof_depth, which publishes sensor_msgs/Image in mono8 format. However:

I don’t know how to convert the 8-bit gray value to actual depth in meters. Is there a LUT or scale factor available for this sensor?

The topic /tof_depth/camera_info returns zero intrinsics (all zeros in the K matrix), so I cannot project the depth image into a point cloud.

I couldn’t find any calibration or intrinsics related to the TOF sensor in /etc/modalai .

Could you please advise how to:

Obtain the proper depth scale or conversion formula from mono8

Get or generate accurate camera_info for the TOF sensor

Thanks in advance!

In addition, we have updated the SDK to the latest version (1.4.5).
We also tried closing the rangefinder server and enabling the lepton server, but still did not receive any response (please see the attached screenshot).

Hello ,@teddy-zaremba
We tried rotating the ring around the TOF sensor as you suggested, but there was no noticeable change in the focus. Since we don’t have much experience adjusting hardware manually, we’re a bit worried about damaging the lens.

Could you please confirm which exact part of the sensor we should be rotating? I’ve attached a photo of our TOF sensor here so you can point out the correct area to adjust.

To Modalai Team:

Regarding your first question — when I switch to the TOF Depth view in Portal, the screen is always completely black, and the depth values stay at 0. There is no visible image or noise.

For the second point, I’ve attached several photos of the entire drone from multiple angles, including the TOF sensor and its cabling. Hopefully, this gives enough visual context to check for any physical issues.

As for the third question — I’ve tested the other image sensors, and they are all functioning normally. Only the TOF sensor appears to be non-functional.

@teddy-zaremba
Hi,

Thanks for your message.

I'm currently using SDK version 1.4.1, as shown in the screenshot below.

To be honest, I'm not entirely sure whether the TOF IR output is functioning normally, since I don’t know what the expected output should look like. My TOF IR view shows some noise and scattered light spots in the image — I’ve attached a screenshot below for reference.

Additionally, I’ve pointed the TOF sensor at a wall approximately 10 meters away, but there was no visible response or change in the output.

@teddy-zaremba
No, only tof_IR responds. tof_depth always shows 0 no matter what I do or how I move the drone.

I am currently setting up a TOF sensor on my Straling 2 Max drone and have followed the configuration steps provided in your official documentation. I am using the VOXL Web UI to monitor the sensor data.

The TOF sensor appears to be recognized by the system — in the Web UI, I can see the TOF IR (infrared) stream, indicating that the sensor is connected and active. However, I do not see any output for the TOF Depth or Confidence (conf) data — the corresponding image feeds are blank or not updating.

Here is the output of voxl-camera-server -l, which shows that the system detects 5 cameras, including the TOF sensor:

Here is the output of voxl-camera-server -l, which shows that the system detects 5 cameras, including the TOF sensor:

I am currently setting up a TOF sensor on my Straling 2 Max drone and have followed the configuration steps provided in your official documentation. I am using the VOXL Web UI to monitor the sensor data.

The TOF sensor appears to be recognized by the system — in the Web UI, I can see the TOF IR (infrared) stream, indicating that the sensor is connected and active. However, I do not see any output for the TOF Depth or Confidence (conf) data — the corresponding image feeds are blank or not updating.