USing PX4FLOW on Aero RTF

[wliu28]

Hi,

Is there someone using PX4FLOW sensor on Aero RTF drone?

I installed PX4FLOW on aero foll0wing this:http://www.instructables.com/id/Intel-Aero-Drone-Altitude-and-Position-Hold-Using-/ Intel Aero Drone - Altitude and Position Hold Using PX4Flow: 11 Steps (with Pictures) and everything is OK other than the frequency of the output. The output rate is only 0.5 HZ(I know it from QGroundControl). How can I modify the output rate?

Thanks!

[RKint]

> output rate is only 0.5 HZ

Are you using qgroundcontrol to view this? And are you connecting via a telemetry radio?

If yes, then I saw a similar problem. You might try connecting qgroundcontrol via wifi (udp or tcp) and see if you get different results. (expect around 10hz)

I was able to get better radio telemetry performance by changing how mavlink gets initialized on the flight controller (rebuilt firmware and re-flashed)

Details:

In this file:

./Firmware/ROMFS/px4fmu_common/init.d/rcS

change this line:

set MAVLINK_F "-r 1200 -d /dev/ttyS3"

To this:

set MAVLINK_F "-d /dev/ttyS3 -b 57600 -r 2880 -m onboard"

Alternatively, you could update the stream rate directly in the code for the desired mode....

See file: /Firmware/src/modules/mavlink/mavlink_main.cpp

and look for:

configure_stream("DISTANCE_SENSOR", 0.5f);

configure_stream("OPTICAL_FLOW_RAD", 1.0f);

Hope that helps.

- Randy

[wliu28]

Hi RandyK,

Thanks a lot for your reply!

but I can not find the file: /Firmware on my drone. In addition, I flash my FC referring to this::http://www.instructables.com/id/Intel-Aero-Drone-Altitude-and-Position-Hold-Using-/ Intel Aero Drone - Altitude and Position Hold Using PX4Flow: 11 Steps (with Pictures), and then all the output rate(see from qgroundcontrol) has been limited including HIGH IMU , ALTITUDE and so on. Do you know why?

Thanks again.

-Liu

[RKint]

>I can not find the file: /Firmware on my drone

Sorry I was not clear. I downloaded the source code and re-built the flight controller firmware on a desktop linux system (Ubuntu).

Here's How I got the source, how I build it, and how I update or re-flash the drone...

Get the source...

cd ~

mkdir px4

cd px4

git clone https://github.com/PX4/Firmware.git https://github.com/PX4/Firmware.git

Here's how I build it...

cd ~/px4/Firmware

make nuttx_aerofc-v1_default

The previous step creates the following file:

~/px4/Firmware/build/nuttx_aerofc-v1_default/aerofc-v1_default.px4

Then I copy that to the drone (via wifi), I shell into the drone and update the firmware. For me, that looks like this:

copy it...

scp ~/px4/Firmware/build/nuttx_aerofc-v1_default/aerofc-v1_default.px4 root@YOUR_DRONE_IP:/etc/px4-fw/aerofc-v1_default.px4

shell into the drone...

ssh root@YOUR_DRONE_IP

cd /etc/px4-fw

aerofc-update.sh aerofc-v1_default.px4

The update procedure is flaky, so you might have to try that last step a few times if it appears to be stuck in a loop for more than a minute.

I'm not an expert. I'm still trying to get my head around this stuff, but that's what works for me.

>output rate(see from qgroundcontrol) has been limited

Might be related to the band width of your connection in qgroundcontrol.

- Randy