Looptimes...

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Derek
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Looptimes...

Post by Derek »

What does a higher looptime do versus a lower looptime?

I'm asking because Stambo told me to set my looptime to 2500...who am I to argue lol but I've seen some videos and some posts of people having their looptime 1200 to 1300.
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Re: Looptimes...

Post by Derek »

Nevermind that question...I just did a bit of searching and within 2 minutes, I found the answer to my own question.

"In Multiwii/Naze32, looptime is the time it complete a “control loop” in micro second: Sensor measurements, data processing and calculate outputs from PID algorithm ready for the ESCs.The lower looptime the faster it computes commands to the ESCs. Changing looptime will have an effect on your PID values, so don’t expect everyting will just magically get better if you reduce looptime, you will still need to re-tune PID. Generally lower looptime allows higher PID gains. A low looptime should make the copter more sensitive and responsive, but more affected by vibrations.

A common value is around 2500 for most multicopters. That’s because most ESCs have a maximum update rate of 400Hz. Some ESCs even have 600Hz update rate so looptime can be set at 1600. Some argue if the looptime is faster than the max ESC update rates, there is no point to lower looptime further as it won’t have any effect on it. Some even suggest it would result in syncing issues."


That's a good enough explanation that even I understood it, lol.
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Re: Looptimes...

Post by Stambo »

Yup you found what I found. :)
Depends on your ESCs as to whether you want to lower it further.
I will wait until I can afford some oneshot ESCs and then try lowering mine to around 1500 and do some flight tests.
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