SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Mar 05, 2012, 12:02 PM
Just another user
Dennis Frie's Avatar
Denmark, Capital Region of Denmark, Naerum
Joined Feb 2011
1,032 Posts
Quote:
Originally Posted by Henry. View Post
Not necessarily since as i guess it would highly depend on the weather and the angle of the rudder but a quad it would work much better on. A plane that is good balanced and good made should level it self without any inputs as far as the engine is on and if it was not to far out from level or if it was not to windy.

But as said if it was badly out of level when the RTH kicked in so no it wouldnt end well. But since it maybe have to be a kiss solution to be able to fit in the in the code so could any RTH maybe be under the term "use of own risk, it only work under these circumstances:" could then maybe have been in place because it needs a lot of electronics involved if it should be 100% ok and these could cost quite a bit.
Controlling the servos requires interrupts. As the OSD is using an interrupt with low priority, it will give noise on the OSD-text. Furthermore, the CPU-time is pretty limited already. If you use a dedicated OSD-chip you should be able to do it - but in this case you are better off with an extra controller.

Quote:
Originally Posted by msev View Post
Where is battery - and video - connected in the whole circuit?
The video is connected to "Video in/out".

You can supply a stable 5 volt at VCC, or use the RAW-input to connect your battery directly. Just be aware, that the Arduino can't handle very high voltage-input, and can't supply more than 100mA or so. The onboard regulator is pretty small.
Dennis Frie is offline Find More Posts by Dennis Frie
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 05, 2012, 01:01 PM
Registered User
Joined Sep 2010
2,419 Posts
Ubec is stable enough for feeding to vcc right at 5-5.5V? Or would it be better to feed it to raw? In this case i would of course seperately feed power from ubec to gps and seperatly to raw for the circuit...How do you suggest?
msev is offline Find More Posts by msev
Last edited by msev; Mar 05, 2012 at 01:23 PM.
Reply With Quote
Old Mar 05, 2012, 01:21 PM
Just another user
Dennis Frie's Avatar
Denmark, Capital Region of Denmark, Naerum
Joined Feb 2011
1,032 Posts
An UBEC should be fine, but you might wanna add an extra output-capacitor if you have extra load. Just to minimize the ripple.

I did some tests a few days ago - not in relation to the OSD-project, just in general.
http://www.student.dtu.dk/~s092916/p...oise_test.html
(www.dennisfrie.dk)
Dennis Frie is offline Find More Posts by Dennis Frie
Reply With Quote
Old Mar 05, 2012, 01:29 PM
Registered User
Joined Sep 2010
2,419 Posts
I wrote some more stuff into the above post..ubec ground wire i connect to GND pin on arduino right.
msev is offline Find More Posts by msev
Reply With Quote
Old Mar 05, 2012, 05:58 PM
Registered User
Joined Aug 2011
64 Posts
Quote:
Originally Posted by msev View Post
Before you have RTH, you need stabilization and autolevelling for a plane.. You need a suitable gyro and suitable accelerometer...And since computing time on the arduino running the diyosd code is taken up, you'll need an additional arduino..

Controlling just the direction of the yaw servo without stabilizing the plane would lead into loss of the plane in my opinion..
I was able to autolevel my planes' roll axis with 2 gyros. basically if you wanted the plane to turn you held the stick to the left/right for a bit, the plane would bank, and then when you let the stick go the plane would re-level itself and continue flying.
Basically if you use the 2 gyro method you would need one output to control the elevator (altitude) and another to control the ailerons for turning.

If you go for RTH, a separate arduino would be better than having the osd arduino multitasking the whole time. I like to keep my video system separate as much as possible from the control system, as to keep away interference. On a long range FPV plane it is nice to have the video system in one equipment bay and the control system somewhere else on the plane, so it would be easier to have some sort of "RTH module" that would be separate from the osd. This is just my opinion, do whatever you think is easier you could do a y harness to split the gps tx line to the osd and the RTH module.

Just my 2 cents
FPVdude is offline Find More Posts by FPVdude
Last edited by FPVdude; Mar 05, 2012 at 06:29 PM.
Reply With Quote
Old Mar 05, 2012, 06:49 PM
Chilled and served
Henry.'s Avatar
Sweden
Joined Mar 2005
287 Posts
Quote:
Originally Posted by Dennis Frie View Post
Controlling the servos requires interrupts. As the OSD is using an interrupt with low priority, it will give noise on the OSD-text. Furthermore, the CPU-time is pretty limited already. If you use a dedicated OSD-chip you should be able to do it - but in this case you are better off with an extra controller.
Aha so its that packed already, and no interupts with the OSD might not be a good idea so ill agree it wouldnt be that good to implement it in th eOSD chip.

But a standalone RTH software to put into another Arduino could then work instead which you then just connect any gyros to and then connect that to the original one would then be perfect. It would also be more simple and not to say much cheaper then the original ones out there which could cost an arm and a leg sometimes but sure with more advanced electronics which isnt strictly neccesary.

Since it seemed like it was possible to get a more or less leveled flight with only 2gyros (roll and pitch then?), at least in a plane, and not much more it might be an approach to test. That as far its not too windy and the RTH only kicks in when the plane is quite leveled already and not in a spiral roll towards the ground so there might be some conditions if used.
Henry. is offline Find More Posts by Henry.
Reply With Quote
Old Mar 06, 2012, 04:25 AM
Registered User
Joined Sep 2010
2,419 Posts
Quote:
Originally Posted by Dennis Frie View Post
LM1881 circuit done by JayPi (I'm only to blame for the colors )

On this circuit diagram battery + is feeded into A1 not VCC? (so A1 accepts and VCC feeds out power forward into the lm?).

And battery ground ("ubec ground") is just connect somewhere to the black wire on the schematic right?



Quote:
Originally Posted by aSa2 View Post
Thanks for your answer and just to be sure, is that correct?
According to this I'm a bit puzzled where is video signal ground on the above circuit diagram?
msev is offline Find More Posts by msev
Last edited by msev; Mar 06, 2012 at 04:43 AM.
Reply With Quote
Old Mar 06, 2012, 04:31 AM
Registered User
Joined Sep 2010
2,419 Posts
Rimshotcopter, how big is that lcd your a using in post #824? Where did you buy it and how does it handle static?
msev is offline Find More Posts by msev
Reply With Quote
Old Mar 06, 2012, 07:03 AM
Just another user
Dennis Frie's Avatar
Denmark, Capital Region of Denmark, Naerum
Joined Feb 2011
1,032 Posts
Quote:
Originally Posted by Henry. View Post
Aha so its that packed already, and no interupts with the OSD might not be a good idea so ill agree it wouldnt be that good to implement it in th eOSD chip.

But a standalone RTH software to put into another Arduino could then work instead which you then just connect any gyros to and then connect that to the original one would then be perfect. It would also be more simple and not to say much cheaper then the original ones out there which could cost an arm and a leg sometimes but sure with more advanced electronics which isnt strictly neccesary.

Since it seemed like it was possible to get a more or less leveled flight with only 2gyros (roll and pitch then?), at least in a plane, and not much more it might be an approach to test. That as far its not too windy and the RTH only kicks in when the plane is quite leveled already and not in a spiral roll towards the ground so there might be some conditions if used.
In interesting solution could be the new receiver from flytron with integrated accelerometer and gyro. With SimpleOSD open and a GPS you can program a complete system with RTH, stabilisation, OSD etc.
Dennis Frie is offline Find More Posts by Dennis Frie
Reply With Quote
Old Mar 06, 2012, 07:15 AM
Just another user
Dennis Frie's Avatar
Denmark, Capital Region of Denmark, Naerum
Joined Feb 2011
1,032 Posts
Quote:
Originally Posted by msev View Post
On this circuit diagram battery + is feeded into A1 not VCC? (so A1 accepts and VCC feeds out power forward into the lm?).

And battery ground ("ubec ground") is just connect somewhere to the black wire on the schematic right?
No, the "battery +" in that diagram is not used for supply voltage. It's the voltage-divider used to read the voltage of the battery. In the schematic a 12-volt battery will only give you ~3 volt on the A1 input.

You have to connect a stable 5-volt supply to VCC or connect a battery directly to RAW and use the onboard regulator on Arduino. Just be aware of the limitations of the onboard regulator if you use RAW.

Quote:
Originally Posted by msev View Post
According to this I'm a bit puzzled where is video signal ground on the above circuit diagram?
I haven't seen any FPV-systems without common ground (ignoring 2-battery systems). That means normal ground and video-ground should be the same. In most cases, you will just add a ground-loop, if you add "video-ground".
Dennis Frie is offline Find More Posts by Dennis Frie
Reply With Quote
Old Mar 06, 2012, 10:37 AM
Registered User
rimshotcopter's Avatar
United States, CA, Los Angeles
Joined Aug 2009
11,704 Posts
Quote:
Originally Posted by msev View Post
Rimshotcopter, how big is that lcd your a using in post #824? Where did you buy it and how does it handle static?
I purchased it off an ebay vendor, forgot which one however, just look in the A/V section. Here is one in retrospect, I like because because it is 7" where as the one in that post is only 4".

http://www.ebay.com/itm/170648038614...84.m1438.l2649
rimshotcopter is online now Find More Posts by rimshotcopter
Reply With Quote
Old Mar 06, 2012, 06:43 PM
Registered User
Joined May 2008
13 Posts
Quote:
Originally Posted by nils1982ks View Post
Hi Dennis,

thank you for your advice. I tried with the other setting, but saw no big change. Is there a way to change to small characters on all lines?
I think I found a reason for my problem. I tried to use Arduino 1.0 after booting Windows Vista instead of Linux to program my OSD I got a clear picture.

Now I can adjust voltage readouts and do the fine tuning, but I really do not understand the problem with Linux. Does anyone else here use Linux?
nils1982ks is offline Find More Posts by nils1982ks
Reply With Quote
Old Mar 07, 2012, 12:52 AM
Registered User
Joined Sep 2004
40 Posts
Quote:
Originally Posted by nils1982ks View Post
I think I found a reason for my problem. I tried to use Arduino 1.0 after booting Windows Vista instead of Linux to program my OSD I got a clear picture.

Now I can adjust voltage readouts and do the fine tuning, but I really do not understand the problem with Linux. Does anyone else here use Linux?
yes, I do and I had the same problems with a new version of ubuntu (avr-gcc-4.5.3). Maybe new compilers do other optimization. Look at post 819 and 820.

joerg
JayPi is offline Find More Posts by JayPi
Reply With Quote
Old Mar 07, 2012, 06:57 AM
Registered User
Joined May 2008
13 Posts
Quote:
Originally Posted by JayPi View Post
yes, I do and I had the same problems with a new version of ubuntu (avr-gcc-4.5.3). Maybe new compilers do other optimization. Look at post 819 and 820.

joerg
It would have been less time consuming to read all the posts I use(d) fedora 15 and just did not believe that this might be the reason...

Nils
nils1982ks is offline Find More Posts by nils1982ks
Reply With Quote
Old Mar 07, 2012, 02:53 PM
Registered User
Joined Sep 2010
2,419 Posts
I started to assemble it on the breadboard.
I need a little help, on my dealextreme arduino nano there isn't vcc written...So is the vcc pin the same as 5V pin on my nano? And is Vin the same as raw pin on pro mini?

And I also have two grounds (GND) written, one is on the side where A1-A7 are written, and the other is on the side that D2-D12 are written...So which ground is the correct one ? Please see attached pics.

Do I connect to the same ground as power and video ground also the gps module ground? Or to the different ground?
msev is offline Find More Posts by msev
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Diy osd karl k FPV Talk 2 May 03, 2011 01:31 AM
Idea New DIY OSD? atari7202 FPV Talk 1 Mar 25, 2011 01:08 AM
Discussion see my own diy OSD video Passion Aerial Photography 7 May 27, 2010 02:28 AM
Discussion REAL homebrew DIY OSD - Check it out! jafoca FPV Talk 8 Jun 29, 2009 07:52 PM
Discussion picoOSD DIY PIC12F683 based OSD in C kbosak FPV Talk 6 Jan 31, 2008 08:47 AM