Position hold using Accelerometer and Gyro

Neigh · Post by **Neigh** » Thu Jun 13, 2013 12:19 pm

Is it possible to lock copter position using accelerometer and gyro ?

scrat · Post by **scrat** » Fri Jun 14, 2013 9:44 am

Nope.

brm · Post by **brm** » Fri Jun 14, 2013 7:57 pm

???
yes - but not with 8 bit.
you need an fpu.

alll · Post by **alll** » Fri Jun 14, 2013 9:45 pm

no, because you don't have an "absolute" reference.

copterrichie · Post by **copterrichie** » Fri Jun 14, 2013 10:31 pm

Personally, I believe it depends upon how Position hold or Position holding is defined. If we are talking about Autonomous holding, then no. That would require GPS however, if we are talking pilot assisted, then that is a totally difference story.

brm · Post by **brm** » Sat Jun 15, 2013 4:15 pm

alll wrote:no, because you don't have an "absolute" reference.

questionable.
their is no need for absolute referencing.
all is relative.

doing sw only accelerometer integration is like creating a flyaway copter.
the drift needs to be corrected with another source.

BradQuick2 · Post by **BradQuick2** » Mon Jun 24, 2013 1:25 am

The answer is: No you can't.

You can integrate the acceleration over time to get velocity and integrate the velocity over time to get position. The problem is that there is always error involved and you are integrating the error as well. So after a few seconds, the error grows to an unacceptable level. Since we are double integrating, it's even worse.

mahowik · Post by **mahowik** » Fri Jun 28, 2013 3:38 am

Yes, it's possible

but you need to apply corrections from absolute position sensor (gps) to remove drift after integration...
viewtopic.php?f=8&t=2503&start=80

And I can confirm that is also possible to do on atmega chips and I have already done it some months ago, but still need some tuning weight of acc/gps complementary filters...

cycleTime in peak no more than 5-6ms...

Also probably you know that Ardu 3.0 released with their own INS based on acc+gps+baro (works on atmega also, i.e. APM 2.5 board) and according to video demo it works great!

http://www.youtube.com/watch?feature=pl ... yPqHeg2v0Y

felixrising · Post by **felixrising** » Fri Jun 28, 2013 6:40 am

Dude, that looks awesome! Just wondering when those nice MegaPirateNG guys are going to get porting again.. unless you are saying ArduCopter now supports Mega2560 out of the box?

copterrichie · Post by **copterrichie** » Fri Jun 28, 2013 11:31 am

felixrising wrote:Dude, that looks awesome! Just wondering when those nice MegaPirateNG guys are going to get porting again.. unless you are saying ArduCopter now supports Mega2560 out of the box?

Yes, there has not been an update since Apr 30, 2013, wonder what is happening?

MultiWii

Position hold using Accelerometer and Gyro

Position hold using Accelerometer and Gyro

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Re: Position hold using Accelerometer and Gyro

Re: Position hold using Accelerometer and Gyro

Re: Position hold using Accelerometer and Gyro

Re: Position hold using Accelerometer and Gyro

Re: Position hold using Accelerometer and Gyro

Re: Position hold using Accelerometer and Gyro

Re: Position hold using Accelerometer and Gyro