Hello, I tried to calibrate the tracking camera using a 4x7 checkerboard with side lengths of 4 cm. I launched voxl-portal to view the camera calibration overlay. Then I placed the checkerboard in various positions and orientations within the red box overlayed on the tracking camera image. However, the calibration process does not progress. I never receive a green (overlay) box and the process remains at 0%.

What should I do to solve this issue?

Command used:
voxl-calibrate-camera tracking -f -l 0.04 -s 4x7

I followed the calibrate camera instructions from here: https://docs.modalai.com/calibrate-cameras/.

Hello ModalAI Team,

It would be great if you provided an easy way to use a Modal AI drone with a motion capture system (such as Vicon). This feature will be helpful to university researchers that may not be able to fly outside (e.g., due to their proximity to an airport) or are interested in experiments where we need accurate drone positions. This feature could increase your consumer base greatly.

Hello,

I am searching for the pixel and lens sizes of the tracking camera. Modal AI's tracking camera data sheet says that the lens size is 1/3.06 inches. But the data sheet for the camera sensor does not work. I looked at other sources for the pixel size (including ArduCam and OmniVision), and they say the pixel size is 3 μm x 3 μm.

Are the lens size (1/3.06 inches) and pixel size (3 μm x 3 μm) correct?

Hello ModalAI Team,

It would be great if you provided an easy way to use a Modal AI drone with a motion capture system (such as Vicon). This feature will be helpful to university researchers that may not be able to fly outside (e.g., due to their proximity to an airport) or are interested in experiments where we need accurate drone positions. This feature could increase your consumer base greatly.

Re: Using Motion Capture Systems (Optitrack) for Position Estimation

This post is a follow-up to the forum post mentioned above. I want to estimate the position and heading of an m500 (with a VOXL computer) using Vicon cameras. I describe my setup and issues below.

Setup:

• A set of Vicon cameras.
• A host computer that runs a custom docker that collects Vicon pose messages and then publishes those messages via ROS. This computer is also my ROS master. This computer also runs QGroundControl.
• A VOXL drone that runs the roskinetic-xenial:v1.0 docker image, has the run_mavros.sh script from Modal AI, and knows that the host computer is the ROS master.
• In addition, I installed mavros-extras in the roskinetic-xenial:v1.0 docker to access the /mavros/odometry/out and /mavros/odometry/in topics.

The VOXL drone runs in station mode and is connected to my WiFi. The drone can run rostopic echo <topic_name> and see the messages published over the network, including the messages from the docker that publishes the Vicon poses via ROS. QGroundControl also sees the drone whenever the drone is running.

Issues:

1. What EKF2 parameters should I change so the drone uses the Vicon system? I saw another mention that I should set EKF2_AID_MASK = 24, which includes vision position fusion and vision yaw fusion. Is this configuration correct? Do I need to set any other parameters?

2. What VOXL parameter do I need to set (if any) to tell VOXL to use a motion capture system instead of the onboard VIO?

3. PX4 (on the drone) gives me an error when I publish the odometry messages from the Vicon system on the topic /mavros/odometry/out. They mainly relate to the frame IDs used. What should I set for the frame_id and the child_frame_id in the odometry messages?

4. How can I test if PX4 receives the odometry messages via ROS?

@DarkKnightCH and @IC, were you able to solve the issues you were experiencing in the post referenced above?

Hello, I am trying to calibrate the stereo camera using the instructions on the website (https://docs.modalai.com/calibrate-cameras/). I use the following command to start the calibration process:
voxl-calibrate-camera stereo -l 0.04 -s 4x7

I tried to view the calibration progress via the voxl-portal's Camera Calibrator Overlay. The Camera Calibrator Overlay option appears in the voxl-portal drop-down menu. However, the stereo view with overlay never appears.

When I try to exit camera calibration (via Ctrl + C), the program hangs and I have to exit the terminal to stop the program.

What should I do to solve the issue with the camera calibrator overlay and the stereo camera calibration?

Hello, I tried to calibrate the tracking camera using a 4x7 checkerboard with side lengths of 4 cm. I launched voxl-portal to view the camera calibration overlay. Then I placed the checkerboard in various positions and orientations within the red box overlayed on the tracking camera image. However, the calibration process does not progress. I never receive a green (overlay) box and the process remains at 0%.

What should I do to solve this issue?

Command used:
voxl-calibrate-camera tracking -f -l 0.04 -s 4x7

I followed the calibrate camera instructions from here: https://docs.modalai.com/calibrate-cameras/.