On Wed, Feb 22, 2012 at 3:59 PM, Bart Remes <
address@hidden> wrote:
> the status is
>
http://www.youtube.com/watch?v=vaxpE3svamo&list=UUGS-Ra1fPexk01KYIBeySRQ&index=2&feature=plcp
>
> still have to implement (and test) quat initialisation. very important when
> your imu is no in a normal oriantation
>
https://github.com/paparazzi/paparazzi/issues/132
>
> and the atmov team is doing the best to implement the gps coordinated turn
> for int_cmpl_quat.
> first step is test this:
>
https://github.com/paparazzi/paparazzi/issues/130
>
>
> Bart
>
> On Wed, Feb 22, 2012 at 1:08 AM, Chris Wozny <
address@hidden> wrote:
>>
>> Does anyone at TU Delft know the status of this project? I'm looking
>> at it and it looks quite robust. I'd be curious to try it with our
>> Mini-Vertigo. Are there any limits to the control laws for this branch
>> like trying to fly a fixed-wing at 90 degrees? The quadshot would see
>> similar issues from autonomous control and singularities as ours does
>> and this does look like the right direction for our project. Thank you
>> for pointing me this out to me Bart and Roman!
>>
>> - Chris
>>
>> On Tue, Feb 21, 2012 at 4:22 PM, Roman Krashanitsa
>> <
address@hidden> wrote:
>> > I looked at the
>> >
>> >
https://github.com/tudelft-atmos/paparazzi/tree/quadshot/sw/airborne/firmwares/rotorcraft/stabilization
>> > branch and the changes look very solid. I think this is the way to go.
>> >
>> > Roman
>> >
>> >
>> > 2012/2/21 Bart Remes <
address@hidden>
>> >>
>> >> chris,
>> >>
>> >> look at the
https://github.com/tudelft-atmos/paparazzi/network
>> >>
>> >> they are making the quatshot autonomous.
>> >>
>> >> It will do basically the same as the vertigo but with
>> >> other controls organs.
>> >>
>> >> Bart Remes
>> >>
>> >>
>> >> On Friday, February 17, 2012, Roman Krashanitsa wrote:
>> >>>
>> >>> Chris, it was not very much hovering but flying at 80-85 pitch. Moving
>> >>> very slowly.
>> >>> But then it can transition to essentially 7 deg pitch horizontal
>> >>> flight.
>> >>>
>> >>> Yes, it works totally fine in auto2.
>> >>>
>> >>> Roman
>> >>>
>> >>> 2012/2/17 Chris Wozny <
address@hidden>
>> >>>>
>> >>>> Felix,
>> >>>>
>> >>>> I know in the past when we used IR sensors instead of an IMU, we just
>> >>>> mounted the IR sensors on this aircraft such that it thought it was
>> >>>> level when flying at high angles of attack. This is why I believe
>> >>>> such
>> >>>> a pitch offset will allow the aircraft to fly horizontally with high
>> >>>> AoA's (especially since Roman has worked with essentially a prior
>> >>>> version of the same aircraft.) I understand what you're saying about
>> >>>> the mechanics being different when hovering vs. horizontal flight.
>> >>>> However, this aircraft will just fly around horizontally with a very
>> >>>> high AoA and is capable of hovering in AUTO1 (my memory is foggy
>> >>>> about
>> >>>> it hovering in AUTO2.) I hope that my explanation is a little clearer
>> >>>> than mud :)
>> >>>>
>> >>>> - Chris
>> >>>>
>> >>>> On Fri, Feb 17, 2012 at 1:00 PM, Felix Ruess <
address@hidden>
>> >>>> wrote:
>> >>>> > Hi Chris,
>> >>>> >
>> >>>> > I'm not sure what you expect by telling the aircraft it is
>> >>>> > horizontal
>> >>>> > while
>> >>>> > it actually is pitched up at 80deg. You can do that, but what
>> >>>> > exactly
>> >>>> > do you
>> >>>> > hope to achieve by that?
>> >>>> > The fixedwing firmware really won't work properly with that
>> >>>> > (without
>> >>>> > modifications that is), as the guidance/stabilization there assumes
>> >>>> > a
>> >>>> > CTOL
>> >>>> > without hover capability. Also stuff like roll basically becomes
>> >>>> > yaw
>> >>>> > when
>> >>>> > you suddenly hover, etc.
>> >>>> > If you have an aircraft capable of both, VTOL/hover and transition
>> >>>> > to
>> >>>> > normal
>> >>>> > flight, you probably want to base that on the rotorcraft firmware
>> >>>> > (just like
>> >>>> > the quadshot, but which is arguably much more like a quadrotor in
>> >>>> > hover) or
>> >>>> > maybe even make a new firmware taking from the others what you
>> >>>> > need...
>> >>>> > What we call a firmware is "just" a main.c with a collection of
>> >>>> > appropriate
>> >>>> > peripherals and subsystems listed in a bunch of makefiles.
>> >>>> > Ok, maybe that is a bit simplified, but basically that's it ;-)
>> >>>> >
>> >>>> > Regarding the singularities (of the euler angle representations):
>> >>>> > Even if your estimation does not have any (e.g. ahrs
>> >>>> > int_cmpl_quat),
>> >>>> > if the
>> >>>> > control is using euler angles, you can of course still run into
>> >>>> > singularities there... basically anything that takes euler angles
>> >>>> > as
>> >>>> > inputs
>> >>>> > is potentially prone to problems around the singularities.
>> >>>> >
>> >>>> > Cheers, Felix
>> >>>> >
>> >>>> > On Fri, Feb 17, 2012 at 8:31 PM, Roman Krashanitsa
>> >>>> > <
address@hidden> wrote:
>> >>>> >>
>> >>>> >> Chris,
>> >>>> >>
>> >>>> >> Most possibly, yes. Also this is easy to check - just make
>> >>>> >> modifications
>> >>>> >> and look at the telemetry values, it should show 0 deg pitch at
>> >>>> >> aircraft
>> >>>> >> hovering orientation.
>> >>>> >>
>> >>>> >> Roman
>> >>>> >>
>> >>>> >> 2012/2/17 Chris Wozny <
address@hidden>
>> >>>> >>>
>> >>>> >>> All,
>> >>>> >>>
>> >>>> >>> If I have a fixed-wing aircraft capable of hovering at high angle
>> >>>> >>> of
>> >>>> >>> attack (80-90 degrees), would it be possible for me to just
>> >>>> >>> change
>> >>>> >>> the
>> >>>> >>> BODY_TO_IMU rotation for theta to that angle of attack so that it
>> >>>> >>> could
>> >>>> >>> hover at that angle? I'm sure I'd have to adjust some PID gains
>> >>>> >>> for
>> >>>> >>> it to
>> >>>> >>> function properly. Also, if this is possible, would I have to
>> >>>> >>> worry
>> >>>> >>> about
>> >>>> >>> singularities at that angle even though I'm using complementary
>> >>>> >>> quaternions
>> >>>> >>> on the dev branch?
>> >>>> >>>
>> >>>> >>> Best,
>> >>>> >>> Chris