[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Paparazzi-devel] which stabilization subsystem is more stable ?

From: Prof. Dr.-Ing. Heinrich Warmers
Subject: Re: [Paparazzi-devel] which stabilization subsystem is more stable ?
Date: Mon, 22 Dec 2014 12:05:54 +0100
User-agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; de-DE; rv:1.4) Gecko/20030619 Netscape/7.1 (ax)

Hi  Eltonwu ,

we fly an wing aircraft Twin Star (1,8kg) with an 460g camera without stabilization inside.
The shutter time is fixed to 1ms and the   aperture is variable.
A club member fly this camera also with a mikrokopter multicopter (total mass in the 4kg range) with a backstepping stabilization control system and good results.

The Paparazzi kroozSD has a additional acceleration sensor with a bandwidth of only 17 Hz. like the current mikrokopter electronics. So this muticopter has no propeller vibrations induced (4000RPM results to 67 Hz) disturbance like all the other. On the other side the stabilization PD control system in paparazzi is not the best to take photos. The backstepping control system generates less disturbance but is not implemented in Paparazzi yet.

In the multikopter forum there are many discussions of the use of different cameras: 1. Cameras with CDD sensors need less light than cameras with CMOS sensors. 2. Cameras with inside stabilization have to be avoided since the vibrations of the propellers make the inside control system unstable. 3. Old cameras (150g) with CCD sensors 4 mpixel generate better results than modern cameras with 16 mpixiel CMOS sensors.

For you  muticopter try the following:
1. use damping balls between the muticopter frame and the camera mount system. 2. test to mount the battery together with the camera (mass helps again vibrations)
3. balance the propellers very well.
4  test to use the same acceleration 17Hz sensor like the kroozSD
5. for future work implement the backstepping  control system in Paparazzi

If i found a student  for the last point, i will generate the work.



Eltonwu schrieb:

In the wiki page, I found 4 stabilization subsystem:


In my opinion,performance of float is more powerful than int. Am I right?
another question is which is more stable between quat and euler? In the wiki
page I found quat is no gimal lock so it can fly in regimes close or at
these singularities (e.g. acrobatics or transitioning vehicles). I just want
fly more stable and take It make more sense to use eluer instead
of quat (search the source code I found the kroozSD use the int_euler, so I
think euler is more stable than quat?)

Thank you very much in advance

View this message in context:
Sent from the paparazzi-devel mailing list archive at

Paparazzi-devel mailing list

reply via email to

[Prev in Thread] Current Thread [Next in Thread]