paparazzi-devel
[Top][All Lists]
Advanced

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

Re: [Paparazzi-devel] Strange Servo Deflection Problem


From: Chris Wozny
Subject: Re: [Paparazzi-devel] Strange Servo Deflection Problem
Date: Mon, 30 Jan 2012 12:24:43 -0700

Helge and Andre,

The issue came from switching channels 1 and 2. For some reason I was
getting roll/pitch on my left stick and throttle/rudder on my right
stick so I changed channels 1 and 2 in the T7cap.xml file. I remember
reading somewhere before that channel 1 is only non-negative real
values, but I didn't think twice about it since I was getting a tiny
amount of deflection. I believe this small amount of control surface
deflection came from some residual noise in the system when the
control stick was fully pitched down. Switching channels 1 and 2
should resolve my issue then I must change the order of my servos
since left stick and right stick were originally reversed.

Thanks for all of your help!
Chris
--
University of Arizona MAV

On Mon, Jan 30, 2012 at 11:50 AM, Andre Devitt <address@hidden> wrote:
> Can you try running the autopilot (prop off) on the plane and looking
> at the following values.
>
> First, in the GCS go to the settings tab and find the TELE_FBW_MODE
> radio button. It will probably be o  0, change it to 1 and then open
> up the Messages window. (In paparazzi center, tools->messages)
>
> Next, in the GCS verify that you are in manual mode. (bottom left of
> the GCS, should say
>  Manual, Auto1 or Auto2, or Home).
>
> Now open the messages window and look at the Commands window. This is
> an array of values range [-9600 to 9600]. The order should be
> throttle, roll, pitch, yaw. Verify with your tx sticks changes these
> values in the proper direction and go to (at least close to) full
> travel. That is, full pitch should read +9600 in the third element of
> array, full negative pitch should read about -9600  in that same
> element.
>
> Once you've verified that all commands are correct, you can check the
> actuators message. These are the pulse widths being sent to the servos
> (approx 1000-2000ms for all your servos from looking at airframe,
> tends to be the standard). Verify that these actuator values are
> changing as you would expect them to and see if they hit any limits
> when going to positive pitch.
>
> These steps should help you isolate whether your problem is in the
> intermediate commands paparazzi generates or the commands sent to
> servos.
>
> Another thing to check is the RC values (actually should probably
> check this first). After setting the TELETRY_FBW_MODE to 1 as I said
> at the top of the post you should  see a message called "RC". This
> message has the RC values coming from the TX to paparazzi. Take a look
> at them and make sure they make sense in terms of sign and magnitude
> in the same way as the commands section.
>
> Andre.
>
> On Sat, Jan 28, 2012 at 3:12 PM, Helge Walle <address@hidden> wrote:
>> Hi,
>>
>> It seems you have the opposite order on ch1 and ch2 compared to my Futaba
>> 10CG in 7ch mode. could that be the problem?
>>
>> This is my radio file:
>> <!DOCTYPE radio SYSTEM "radio.dtd">
>> <radio name="T10CG7" data_min="900" data_max="2100" sync_min="5000"
>> sync_max="15000" pulse_type="POSITIVE">
>>   <channel ctl="right_stick_horiz" function="ROLL" min="1936" neutral="1525"
>> max="1110" average="0"/>
>>   <channel ctl="right_stick_vert" function="PITCH" min="1107" neutral="1520"
>> max="1933" average="0"/>
>>   <channel ctl="left_stick_vert" function="THROTTLE" min="1107"
>> neutral="1107" max="1933" average="0"/>
>>   <channel ctl="left_stick_horiz" function="YAW" min="1929" neutral="1516"
>> max="1104" average="0"/>
>>   <channel ctl="switch_G" function="CALIB" min="963" neutral="963"
>> max="2069" average="10"/>
>>   <channel ctl="VRA" function="GAIN1" min="964" neutral="1489" max="2070"
>> average="0"/>
>>   <channel ctl="switch_C" function="MODE" min="2072" neutral="1511"
>> max="967" average="10"/>
>> </radio>
>>
>> Helge.
>>
>> 2012/1/28 Chris Wozny <address@hidden>
>>>
>>> Andre,
>>>
>>> That is correct, I'm building against paparazzi dev branch. I believe
>>> the radio channels are correct because the sticks all correspond to
>>> what I want them to do. Left stick vertical is throttle while
>>> horizontal is rudder, right stick vertical is pitch while horizontal
>>> is roll (the only thing that is off is that pitch down only moves the
>>> control surfaces down about 5% of the control surface movement when
>>> pitching up.) The only thing I don't know about is any of the
>>> switches, they don't seem to correspond to anything I've set in the
>>> T7cap configuration since currently switch B controls the APs mode.
>>> You are right about the autopilot section looking funky, our aircraft
>>> is a VTOL fixed wing so for AUTO1 we'd like to fly it with a certain
>>> altitude or just hover at a certain attitude. We haven't actually been
>>> able to test those AP modes since we're still trying to get it to fly
>>> in manual. Any thoughts or comments on the servo deflection, or
>>> anything else for that matter would be appreciated!
>>>
>>> Best,
>>> Chris
>>> --
>>> University of Arizona MAV
>>>
>>> On Fri, Jan 27, 2012 at 8:10 PM, Andre Devitt <address@hidden>
>>> wrote:
>>> > Have you looked at the commands message in the messages window?
>>> >
>>> > Maybe radio channels are configured incorrectly. I think throttle is
>>> > clipped
>>> > to positive only, and if throttle radio channel was being interpreted as
>>> > pitch might see that behavior.
>>> >
>>> > Some sections of your airframe file are also only relevant for
>>> > rotorcraft
>>> > firmware, not sure what you used as template. The AP mode section stuck
>>> > out.
>>> >
>>> > This airftame file is building against current github paparazzi-devel
>>> > head,
>>> > correct?
>>> >
>>> > On Jan 27, 2012 7:48 PM, "Chris Wozny" <address@hidden> wrote:
>>> >>
>>> >> All,
>>> >>
>>> >> For some reason I have good range on my deflection for my servos when
>>> >> I roll. When I pitch up, the deflection is also good and just how I
>>> >> want it. However, when I pitch down, my servos barely move from
>>> >> neutral. Has anyone run into this situation before? It's got to be
>>> >> some sort of pitch gain somewhere, but I'm flying in MANUAL. I've
>>> >> linked copies of my airframe and my radio file here:
>>> >>
>>> >> http://ece.arizona.edu/~cwozny/T7cap.xml
>>> >> http://ece.arizona.edu/~cwozny/minivertigo_lisa_m.xml
>>> >>
>>> >> Best,
>>> >> Chris
>>> >> --
>>> >> University of Arizona MAV
>>> _______________________________________________
>>> Paparazzi-devel mailing list
>>> address@hidden
>>> https://lists.nongnu.org/mailman/listinfo/paparazzi-devel



reply via email to

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