search

PX4 / PX4-SITL_gazebo-classic

Set of plugins, models and worlds to use with OSRF Gazebo Simulator in SITL and HITL.
http://dev.px4.io/simulation-gazebo.html
379 stars 798 forks source link

Parachute deployment does not appear to work #786

Open hamishwillee opened 3 years ago

hamishwillee commented 3 years ago

The instructions in https://docs.px4.io/master/en/simulation/gazebo.html#simulated-parachute-flight-termination explain that you can simulate parachute deployment by first launching the simulator with:

make px4_sitl gazebo_if750a

Then force flight termination.

I tested this by forcing an altitude safety geofence violation (set a low altitude ceiling and flew straight up). The flight termination happens - there are GCS notifications and the vehicle crashes. But there is no indication that a parachute is deployed.

How would you know? Shouldn't we see something appear on the screen?

Jaeyoung-Lim commented 3 years ago

@hamishwillee Thanks for posting this issue,

The main reason is that the pwm values of the flight termination has changed on the firmware side, and we need to adjust the parachute threshold value.

However, when trying to fix the problem I noticed also that the firmware is emitting termination pwm values when arming. Therefore the parachute is being deployed before takeoff.

Since there is no way from the simulation side to distinguish flight termination and a normal actuator output now, I am not sure how I can fix this. @bresch Did something change on the termination pwm values?

bresch commented 3 years ago

@Jaeyoung-Lim Something might have changed on the Firmware side but I'm not aware of it. At boot, the PWM signals should go to their "disarmed" and not "failsafe" (used for termination) values.

Jaeyoung-Lim commented 3 years ago

@bresch I think this wasn't the case before, but now the disarmed value and failsafe values have become identical. Would you have any idea what might have introduced this change?

bresch commented 3 years ago

Would you have any idea what might have introduced this change?

Nope... :(

akshata-1 commented 3 years ago

@Jaeyoung-Lim Is this issue resolved?

Jaeyoung-Lim commented 3 years ago

@akshata-1 No, unfortunately I was not able to fix it, as you can see in the thread

iamrajee commented 2 years ago

I'm facing the same issue. Is there any update? @Jaeyoung-Lim

DronecodeBot commented 1 year ago

This issue has been mentioned on Discussion Forum for PX4, Pixhawk, QGroundControl, MAVSDK, MAVLink. There might be relevant details there:

https://discuss.px4.io/t/px4-community-q-a-may-10-2023/32060/1

DronecodeBot commented 1 year ago

This issue has been mentioned on Discussion Forum for PX4, Pixhawk, QGroundControl, MAVSDK, MAVLink. There might be relevant details there:

https://discuss.px4.io/t/px4-maintainers-call-may-16-2023/32137/1