FC v2 Collision prevention issue with voxl 2

Jetson Nano

Sean Hickey

I was able to identify the issue.

mpc_pos_mode - acceleration based doesn't call Collision Prevention in any of the newest PX4 builds..

You need to use mpc_pos_mode - Simple Position Control (0) or mpc_pos_mode - smooth position control (3).

I was able to test this on a similar setup, and confirmed that collision prevention only worked with the mpc_pos_mode indicated above, and notably did not with mpc_pos_mode acceleration.

Jetson Nano

@Sean-Hickey that great, just making sure, did you use optical flow with FC?

Also could you let me know which branch you used, or the Px4 built file. i want to test it out in my setup.

Sean Hickey

@Jetson-Nano

I used VIO with FC, but the path from obstacle detection to Collision Prevention is unchanged between the 2 modes.

I used the mainline ModalAI PX4 SDK branch. I can share the built px4 deb build with you if that's helpful, but I would try changing the mpc_pos_mode parameter first on your current build to see if that fixes your issue.

Jetson Nano

@Sean-Hickey
I already checked with changing the MPC_POS_MODE, did not work.

Could you share the file, I would like to test it out.

Sean Hickey

@Jetson-Nano

https://drive.google.com/file/d/1FmaW4kXma6pxjQO86WugNJq9-5zZ75gU/view?usp=sharing

I attached the link above, I am using parameters:

MPC_POS_MODE: Simple position control
CP_DIST 1.5 m
CP_DELAY 0.4 s
CP_GUIDE_ANG : 0 deg
CP_GO_NO_DATA: Enabled

Sean Hickey

@Jetson-Nano

If this doesn't work, on the mavlink console (after testing the collision prevention) call:
listener obstacle_distance_fused 1
listener collision_constraints 1

and let me know the results.

Jetson Nano

@Sean-Hickey
sorry to disturb you again .
I am not able to flash with the deb file, could you please share the .px4 file

Jetson Nano

@Sean-Hickey

I tested with this firmware modalai_fc-v2_1.14.0-2.0.133.px4 from (http://voxl-packages.modalai.com/dists/fc-v2/sdk-1.6/ ) and it worked, but there is no uavcan thats the only problem.

I checked with the parameters you mentioned.

When i reduce the cp_dist it stops working but with 1.5 m it is working.

Eric Katzfey

@Jetson-Nano Can you rebuild to add UAVCAN? The code is here: https://github.com/modalai/px4-firmware/tree/v1.14.0-2.0.133-dev