Home navigation question

Here is the place for all your dsPic or autopilot questions.

Moderator: lukasz

Re: Home navigation question

Postby Tom » Fri Mar 18, 2011 5:21 pm

@Jippieee: As lukasz said, the GPS position can vary when having a bad lock indoor. However, I never experienced the difference to be 1km. Mostly about 100m...
User avatar
Tom
Site Admin
 
Posts: 1016
Joined: Fri Nov 13, 2009 6:27 pm
Location: Belgium

Re: Home navigation question

Postby Jippieee » Fri Mar 18, 2011 8:51 pm

lukasz wrote:@Jippieee were you inside a building when this was happening?
I also see the same but when I'm in my house, when out outside all seems to be fine.


Yes, this was inside. Could this affect the GPS?
Jippieee
 
Posts: 24
Joined: Mon Jul 19, 2010 1:50 pm

Re: Home navigation question

Postby Tom » Fri Mar 18, 2011 9:14 pm

Oh yes very much.
GPS uses the time difference between signals. Inside or when you're between 2 large buildings those signals get reflected so those time differences change due to those reflections.
No worries!
User avatar
Tom
Site Admin
 
Posts: 1016
Joined: Fri Nov 13, 2009 6:27 pm
Location: Belgium

Re: Home navigation question

Postby Tom » Sat Mar 19, 2011 8:04 pm

@Jippieee:
I updated the latest development software on the SVN (and also flight tested it today). Can you confirm this development version or the 0.5.2 works fine?
User avatar
Tom
Site Admin
 
Posts: 1016
Joined: Fri Nov 13, 2009 6:27 pm
Location: Belgium

Re: Home navigation question

Postby Jippieee » Sat Mar 19, 2011 9:21 pm

Tom wrote:@Jippieee:
I updated the latest development software on the SVN (and also flight tested it today). Can you confirm this development version or the 0.5.2 works fine?


Ok thanks Tom. I may not have time until next weekend to test the new firmware but i will give it a go as soon as I can. I had a look early this afternoon but unfortunately the SVN was not updated at that time so I reverted to the latest firmware from the Wiki download page and had another two flights today. The homing function was working now but I observed something strange: during auto flight the plane sometimes makes abrubt moves like rolling or climb/dive sharply for a few seconds. Especially in the dive situation I had a few times that I needed to switch over to manual. This all happened the second flight, the first flight went flawlessly.
Could this be configuration or GPS related or do you have a suggestion to look for a problem source? I now fly on 2.4GHz with a futaba/orange receiver. The abrubt moves also happened with the transmitter turned off, which sets the receiver in a fail safe mode so no receiver glitches should be expected. The abrubt moves defenately go beyond the configured maximum roll and climb angle.

Funny detail: I accidently took off the second flight in auto mode and it was really funny to see the plane NOT respond on my commands but flew away nice and gently.

O and yes, next time I will put an offset with a minimum of the radius because I got crazy with the plane circling around my head ;)
Jippieee
 
Posts: 24
Joined: Mon Jul 19, 2010 1:50 pm

Re: Home navigation question

Postby Tom » Sat Mar 19, 2011 11:27 pm

Can you send the datalog? It shows more info about what was going on.
The only thing I can think of for the moment are vibrations, but the datalog should reveal more information.
User avatar
Tom
Site Admin
 
Posts: 1016
Joined: Fri Nov 13, 2009 6:27 pm
Location: Belgium

Re: Home navigation question

Postby sidewind » Tue Mar 22, 2011 8:23 pm

Hi Tom,

I didn’t have time the past weekend – although the weather was beautifull. On weekdays, we can’t fly here, we’re in the CRT of the Military Airbase Kleine-Brogel.
Now, the F16’s fighters are all day in the air and for the upcoming weekend, I’m visiting a fair in Karlsruhe. On my way, I’ll visit ACT.
For now, I’ve set the threshold on max and give it a try asap.
What is the size of your prop you’re using on your Ultra Funjet, I want to know because I have the same engine (Thyphoon 6/15 with 6.5x5 prop.)



Michael
--> Please visit my big scale models side: http://www.sidewind.be <--
sidewind
 
Posts: 9
Joined: Sun Jan 17, 2010 1:10 am
Location: Belgium

Re: Home navigation question

Postby Tom » Tue Mar 22, 2011 8:29 pm

I use a 7x5 but it's a typhoon 6/20 (on 2s lipo).
The power isn't very large for take-off, but once in the air there are no problems!


You can easily calculate it here: http://www.s4a.ch/eflight/motorcalc.htm
User avatar
Tom
Site Admin
 
Posts: 1016
Joined: Fri Nov 13, 2009 6:27 pm
Location: Belgium

Re: Home navigation question

Postby Jippieee » Fri Mar 25, 2011 8:38 pm

Hello Tom,

I have the data log attached to this message. It would be nice if you give it a look.
Just got a fresh new SVN today and downloaded the firmware. Hopefully tomorrow some more flights!
Attachments
trim.jpg
trim flight
trim.jpg (328.85 KiB) Viewed 7666 times
trim.kml
This looks better (first trim flight)
(136.47 KiB) Downloaded 508 times
home_glitch.kml
Flight with glitches / home offset
(128.27 KiB) Downloaded 488 times
Jippieee
 
Posts: 24
Joined: Mon Jul 19, 2010 1:50 pm

Re: Home navigation question

Postby Tom » Fri Mar 25, 2011 9:56 pm

@Jippieee: Thanks for the KML. Could you better describe the problem and also attach the datalog .xml file? It looks like a weird flight, so could you also include the navigation commands?
For a basic test flight I usually fly a circle with a radius of about 120m.

Be aware that the SVN servers contain development code. The good & tested versions are on the download page :-)
User avatar
Tom
Site Admin
 
Posts: 1016
Joined: Fri Nov 13, 2009 6:27 pm
Location: Belgium

PreviousNext

Return to Firmware

Who is online

Users browsing this forum: No registered users and 3 guests

cron