# VOXL 2 VOA not working

Source: https://forum.modalai.com/topic/2875/voxl-2-voa-not-working
Category: VOXL 2 and VOXL 2 Mini (https://forum.modalai.com/category/26/voxl-2-and-voxl-2-mini)
Tags: voxl-2
Posted: 2023-11-17 08:10:00 UTC by Jetson Nano
Replies: 2 · Views: 582

## Jetson Nano · 2023-11-17 08:10:00 UTC

We are testing VOXL2 Collision avoidance with SDK 0.9.5.

VOXL Vision PX4 is enabled and running and along with it are the below functionalities enabled,
- VIO is renabled and running 
- Position hold is working and stable when testing the drone 
- DFS Server also enabled and running and voa_pc point cloud data can be visualised in VOXL Portal

-> en_voa is set to true in voxl-vision-px4 config.

Point cloud data is being published from  voxl-dfs-server and can be seen in voxl-inspect-serices.
![inspect-services.png](https://forum.modalai.com/assets/uploads/files/1700208336324-inspect-services.png) 

- We have accurately specified extrinsics relation for body to stereo in extrinsics.conf
- PX4 parmeters are set as per documentation,
- Distances can be viewed in debug_stereo_linescan as well as in obstacle distances in QGC which are fairly accurate.
![voa_linescan.png](https://forum.modalai.com/assets/uploads/files/1700208303561-voa_linescan.png) 
![QGC.png](https://forum.modalai.com/assets/uploads/files/1700208313262-qgc.png) 

dfs_disparity scale and voa_pc are both present in the VOXL portal.
![Screenshot from 2023-11-17 12-34-08.png](https://forum.modalai.com/assets/uploads/files/1700208367696-screenshot-from-2023-11-17-12-34-08.png) 

Stereo sensors are calibrated as reprojection errors are under 0.2 but **collision prevention is not working during flight during Position hold mode/Altitude mode**.

@Chad-Sweet @Alex-Gardner

## Reply by Cliff Wong (ModalAI staff) · 2023-11-18 00:59:07 UTC

Hi there, do you have COM_OBS_AVOID=1 (enabled)? You can set the parameter directly  (params) or there's a menu option in QGC.

If so, can you arm the drone? With *_AVOID=1 I suspect all will work as you are seeing ```obstacle_distance``` data on mavlink.
If not, then you should get a QGC report "Avoidance system not ready"--let us know which case you end up with.

## Reply by Jetson Nano · 2023-11-18 06:36:10 UTC (in reply to Cliff Wong)

@Cliff-Wong When I set COM_OBS_AVOID = 1 the system says it is not ready to fly, but I am not getting any messages as Avoidance System not ready