More news.. (Including new 2Ch OptoCoupler and ArduIMU Flat issue)

For some reason my left index finger hurts me, so i can't type very well. ;-)

I'm setting up ArduIMU and ArduPilot SVN repertory, in conjunction with Google code. In that way you will be able to track all the changes made to the code and spot the differences between revisions with the possibility to comment (or complain) about it.

Lets do an interesting example, if you go to google code repertory for ardupilot and you click in the tab "source" and then in the option "Changes", or just click here: You will see a list of all the revisions of the codes, any change we do to the code will be displayed as a new revision.

Now click on revision 5 "r5", over there you will see the log message (i forgot to say something) and the "Affected files". The affected files tells you if i have made a modification, addition, etc. to the specified source file.

Now lets go to the point, if you want to see the changes made to the file "/trunk/GPS_UBLOX.pde" in r5 just click on the "diff" link. In the next page you will see a comparation from r1 and r5 files, scroll down and you will find a tiny correction in the checksum verification for the uBlox parser in red (old one) and green (for the new one), spotted and correct by Jason (hehe, my bad). This is what you should see:


Now for the store i have include a new and improved 2ch optocoupler:

Its pretty small (in the picture looks huge) but in reality is very tiny. Can be use as single or dual channels. Not to mention that has less components (smaller and cheaper) and more convenient for ucontrollers, because you don't need to supply 5V to power the board in the input side, you can just connect the 3.3V or 5V PWM signal output from your system or receiver (with ground) and you are done!

-You can get the stand alone board from here.
-Or the assembled version from here.


For ArduIMu flat version, seems that the High Pass filter on the board is causing problems for some applications, so this the solution:
-I will not populate the 1 Mohms resistors anymore.
-The 4.7uF capacitor will be replaced by a zero ohms resistor, just to make a bridge, click here.

You can see here the difference between the original board and the new board.

And whalaa!! Problem solved. If you want me to remove your HP, just mail it to me and i will do it for free.


-UPS shipping problem!! For some reason the store page is displaying the full prices (and no the prices with discount) for international shipments. If you want to use UPS for international but the displayed price is very expensive just email me and i will give you the real price and i will refund it.

Best regards

Views: 834

Comment by William Premerlani on November 15, 2009 at 6:29pm

I think your 2 channel optocoupler is a great idea. I can see that in addition to providing isolation, you can use it to boost 3 volt TTL signals up to 5 volts.

However, if I connected 4 of them between my receiver and my UAV DevBoard, the DevBoard would not receive any power, because right now it receives power from the receiver.

Suppose I wanted to use your optocoupler for signal boost, but not for isolation, so I would want to tie power and ground from input side to output side. It looks like your assembled board is encapsulated. Does that mean I would have to buy your unassembled board and wire it up the way I want it?

Comment by Morli_ on November 15, 2009 at 6:40pm
the transparent shrink wrap I think can be removed and jumper across will do the job and re shrink , I see the only difference I see between the two ver is the Right Angle Break Away Header

Comment by Jordi Muñoz on November 15, 2009 at 6:48pm
The first version was more complicated and transistors were needed.

@Bill, Yes if you solder 2 wires (5V and GND) from the output servos you can supply the receiver too without problems. In version 3 i will add a solder jumper to do that, ;-) Thanks for the idea.

Comment by Jordi Muñoz on November 15, 2009 at 7:53pm

Yes the booster trick works, i just did the experiment. I soldered the 5V and GND from both side together and i analysed the signals with the oscilloscope, here is the 3.3V input signal from my receiver:

Here is the output signal from the optos:

So your idea is working great! Thanks! Bill.. ;-) Let me know if you need something..
Comment by Andy Geppert on November 15, 2009 at 10:06pm
@Jordi - great work setting up the repositories. That should be extremely helpful. Let us know the link to the ArduIMU one as soon as it is available.

Comment by Pete Hollands on November 15, 2009 at 11:17pm
International Shipping - Yes, the prices were expensive, so I opted for priority mail - that took 3 weeks to arrive in the UK. So I'm very glad that the pricing is now fixed for the faster, tracked shipments.

You may want to look at working with" target="_blank">Cool Components in the UK as a local stockist of your parts. They are sourcing quite a few UAV components from Sparkfun and provide next day delivery to the UK. I have found them to be reliable. e.g. I purchased my Ublox from them.
Comment by simonl on November 16, 2009 at 1:26pm
I'll 2nd Peter's observation about CoolComponents - would be much better for me in the UK ;-)
Comment by endrew on November 17, 2009 at 4:21pm
about the correction in the GPS_UBLOX.pde file - I don't understand. With this small error the cheksum should always fail, and the rc plain shouldn't be able to navigate or get a lock. Yet mine does both! how is it possible?
Comment by Scott Plunkett on November 20, 2009 at 12:56pm
WooHoo - Thanks for the 2 channel optocoupler Jordi! I'll be buying one for my Tracking Antenna Build to work with the new ArduStation Mega. What is the actual Optocoupler part? I'm going to be building a custom board to fit in a tight case with a 6Ah battery, charger, RJ45 to 3 pin servo connectors, etc.

Comment by Jordi Muñoz on November 20, 2009 at 1:17pm
Scott, You need optocouplers for ardustation V1 too, because the servos drain to much power.


You need to be a member of DIY Drones to add comments!

Join DIY Drones

© 2019   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service