Most responsive/lowest latency method of controlling Arducopter?

ArduCopter
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Hi guys, I’ve been looking at the best way to quickly control my drone using a computer program. I’d like to control my drone as quickly as you see in those videos that use Vicon cameras and retro-reflective balls. Is this possible in Arducopter?

I found this link interesting on using a joystick in QGroundControl to control the quadcopter:

https://docs.qgroundcontrol.com/master/en/SetupView/Joystick.html

as it covers the MANUAL_CONTROL Mavlink message:

https://mavlink.io/en/messages/common.html#MANUAL_CONTROL

as well as the more traditional SET_POSITION_TARGET_LOCAL_NED message:

https://mavlink.io/en/messages/common.html#SET_POSITION_TARGET_LOCAL_NED

Which one of these should I be using to reactively and quickly control my drone? Is there any other method that would allow me to tell my drone where to fly with low latency? Cheers.

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There’s a whole section on it here in the docs
https://ardupilot.org/copter/docs/common-gcs-only-operation.html#operation-using-only-a-ground-control-station-gcs
and Guided mode
https://ardupilot.org/copter/docs/ac2_guidedmode.html?highlight=guided#guided-mode

Ordinary old 3DR-copy telemetry radios at 56k (defaults) will provide Guided control without noticeable latency. You might be able to push up their baud rate, but I haven’t tried that with them.
Unless you’ve got masses of communications, the baud rate and latency are unlikely to be an issue, since a copter or any other aircraft will be unable to react instantly anyway.

If you really need low latency and higher throughput, like swarming, then the RFD telemetry radios can be set to higher baud rates, like 115k. There’s no more latency than dedicated RC control and telemetry is much better. You can also turn down the output power if you’re using them at close range or indoors.
By way of example, we’ve started using them for RC Control (TXMOD http://store.rfdesign.com.au/rfd900ux-txmod-v2-bundle/) as well as telemetry.

EDIT: and there’s Guided_NoGPS for when you’ve got some external positioning system

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And check the Blog section for really good articles on Swarming experiments for the common man

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I have an onboard companion computer so bandwidth is not a concern (unless getting all this data uses up too many cycles on the Pixhawk CPU).

The 2 links you kindly gave are interesting but don’t specifically state which is a good low-latency way to control the drone.

Thanks for the blog link. I had no idea there was a blog. I see the “common man” articles publish swarm location data to other drones using GLOBAL_POSITION_INT so that suggests the system is as responsive as those family of messages. i.e. there is not a secret method of controlling drones with low latency.