# VOA not working with ToF

Source: https://forum.modalai.com/topic/3097/voa-not-working-with-tof
Category: Development Drones (https://forum.modalai.com/category/44/development-drones)
Tags: starling
Posted: 2024-02-07 13:27:27 UTC by Jetson Nano
Replies: 4 · Views: 1372

## Jetson Nano · 2024-02-07 13:27:27 UTC

I am trying to do voa in a starling drone which has a ToF, I have enabled voa and also set it to use ToF, but still collision prevention is not working for me, And also I am not getting the obstacle distance messages in QGC

## Reply by Jetson Nano · 2024-02-12 13:25:41 UTC

@tom @Chad-Sweet @Eric-Katzfey Waiting for a response from your side!

## Reply by Alex Kushleyev (ModalAI staff) · 2024-02-13 16:57:55 UTC (in reply to Jetson Nano)

@Jetson-Nano , can you please provide some additional information:

* are you using VOXL1 or VOXL2?
* which VOXL SDK are you using?
* have you verified that TOF sensor is functional (you can do it using `voxl-portal` (cameras or point clouds tab)
* how are you enabling / configuring VOA?
* have you verified that VOA is running and not producing any error messages?

Thank you

## Reply by Jetson Nano · 2024-03-05 15:07:07 UTC (in reply to Alex Kushleyev)

@Alex-Kushleyev 
1. we are using voxl 2
2. SDK version: 1.1.1
3. TOF is functional [working in portal and mapper]
4. Followed the steps in https://docs.modalai.com/voxl-vision-px4-collision-prevention-0_9/ with the following parameters
CP_DIST: 1.5
CP_DELAY: 0.0
CP_GUIDE_ANG: 0.0
CP_GO_NO_DATA: 1
and en_send_voa_to_qgc in voxl-vision-hub.conf is enabled.
5. Yes we can see the VOA point cloud on the portal and running voxl-vision-hub -s shows the distances in line on the terminal.
We verified the distance values and they are accurate but the drone doesn't stop on its own even when we go really slowly at a fixed obstacle under 1.5m

## Reply by Moderator (ModalAI staff) · 2024-03-05 15:43:21 UTC (in reply to Jetson Nano)

@Jetson-Nano Looks like MPC_POS_MODE is needed as well per the documentation https://docs.px4.io/main/en/computer_vision/collision_prevention.html