Re: [Paparazzi-devel] Lisa/M for Bare Bone Attitude Stabilization Only

[Chris Wozny]

I have misspoken, our aircraft is fixed wing, but we may as well just
call it a rotorcraft since it's a VTOL tail sitter and indoors will
essentially only be used in "hover" mode like a rotorcraft. So I guess
instead of asking my initial question, I should ask, can a rotorcraft
in the same configuration fly indoors in attitude stabilization mode
without a ranging sensor like a Maxbotix LV-EZ4? Sorry for the
confusion.

- Chris

On Fri, Mar 23, 2012 at 1:27 AM, Christophe De Wagter
<address@hidden> wrote:
> For the Airplane-mode AHRS filters to work they need your current speed.
> Without speed turns get very wrong. Usually GPS is used. Airspeed is another
> option. In case none of these are available, then you could revert to
> filling in the nominal cruise speed, which is expected to work much better
> than with no speed at all. Or even estimate the speed as function of the
> throttle: throttle off = just-above-stall-speed, max throttle=max-cruise and
> interpolate in between.
>
> This would also be nice for outdoor planes to survive GPS-loss.
>
> Concerning the airframe file you do not need to change/remove anything
> except checking your flightplan that you do not have a GCS timeout exception
> to come HOME (which will not affect manual but will affect auto1)
>
> -Christophe
>
> On Thu, Mar 22, 2012 at 9:09 PM, Chris Wozny <address@hidden> wrote:
>>
>> All,
>>
>> We've got an aircraft that needs to be used solely indoors (no GPS
>> fix) and have to minimize weight. I was wondering if it's possible to
>> use Lisa/M solely for attitude stabilization without the need for a
>> datalink. The only things that will be on the aircraft are contra
>> rotating motor, ESC, three servos, Lisa/M, and the batteries. We would
>> like to essentially drop Lisa/M with Aspirin into our airframe as a
>> replacement for 3 single-axis analog gyros used for stabilization
>> (10.8 grams and 30 mA draw versus 20.4 grams and 45 mA draw). There
>> are also obvious benefits to using the Aspirin IMU for stabilization
>> instead of just gyro stabilization. This would mean we wouldn't need
>> the TELEMETRY, FLIGHTPLAN, GPS, or NAVIGATION subsystems. Could I just
>> leave my airframe configuration as is (it currently is set up to fly a
>> fixed wing outdoors in AUTO2) or could/should I remove any of these
>> subsystems?
>>
>> Best,
>> Chris