OpenServo.com Forum Index OpenServo.com
Discussion of the OpenServo project
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

SparkFun openservo boards

 
Post new topic   Reply to topic    OpenServo.com Forum Index -> Hardware
View previous topic :: View next topic  
Author Message
ahoeben



Joined: 20 Jun 2008
Posts: 20

PostPosted: Thu Jul 09, 2009 8:24 am    Post subject: SparkFun openservo boards Reply with quote

http://www.sparkfun.com/commerce/product_info.php?products_id=9014

Looks like SparkFun did their own version of the OpenServo boards. They look a bit less finicky, but that could just be the pictures. Does anyone have any more details about this version?

update: Looks like its based on the V2 branch...
I came to OpenServo in the V3 era, what functionality is missing in the V2 branch of the hardware?

update: Answering my own question, from http://www.openservo.com/OpenServoV3
# Back EMF speed sensing
# Braking
# Temperature sensor
# 20MHZ clock speed / 400khz interface
Back to top
View user's profile Send private message
ginge
Site Admin


Joined: 14 Jan 2006
Posts: 1031
Location: Manchester, UK

PostPosted: Fri Jul 10, 2009 8:05 am    Post subject: Reply with quote

Good find!

This is the first I have heard about this.

Indeed it is based on the old v2 branch. There are numerous other features int he v3 that you have not listed.

Strangely, the v2 branch, although functional, is no longer supported. I wonder how long it is before we get people on here asking for support.
_________________
http://www.headfuzz.co.uk/
http://www.robotfuzz.co.uk/
Back to top
View user's profile Send private message Send e-mail Visit poster's website Yahoo Messenger MSN Messenger
jharvey
co-admin


Joined: 15 Mar 2009
Posts: 359
Location: Maine USA

PostPosted: Sat Jul 11, 2009 12:33 am    Post subject: Reply with quote

Sweet, out of stock.
Back to top
View user's profile Send private message Visit poster's website
ginge
Site Admin


Joined: 14 Jan 2006
Posts: 1031
Location: Manchester, UK

PostPosted: Fri Aug 28, 2009 9:21 pm    Post subject: Reply with quote

An update to this thread...

I had a friendly chat with the main man over at SparkFun and we have come to a gentlemans arrangement.

As of fairly soon, the v2 branch will be slightly revived so we can backport some of the v3 shiny features. We don't have much room to play with in the atmega 8 so I will be drawing up a sortlist of features that are useful.
I am also going to look at the documentation for the v2 branch, and make sure it is up to scratch.

We will also be addind a link and image on the front page to the SparkFun product. If they can sell a few units, we gain a larger userbase. Win-win.
_________________
http://www.headfuzz.co.uk/
http://www.robotfuzz.co.uk/
Back to top
View user's profile Send private message Send e-mail Visit poster's website Yahoo Messenger MSN Messenger
jharvey
co-admin


Joined: 15 Mar 2009
Posts: 359
Location: Maine USA

PostPosted: Sat Aug 29, 2009 10:24 am    Post subject: Reply with quote

Nice, I haven't looked at the V2 board much. Should I put in a plug to have some extra pads left there for a possible future upgrade that allows Open-Encoder?
Back to top
View user's profile Send private message Visit poster's website
FireBALL



Joined: 24 Jul 2009
Posts: 28

PostPosted: Sat Aug 29, 2009 2:31 pm    Post subject: Reply with quote

Sadly I bought 4 of those without realising the difference. Though i was able to load FW3 but motor is sluggish and feedback response is somewhat confused rather messed up. can any one suggest what can I do with those boards. Is there anyone with extra PCBs of v3 I don't mind hand soldering. I need four.
Back to top
View user's profile Send private message
ginge
Site Admin


Joined: 14 Jan 2006
Posts: 1031
Location: Manchester, UK

PostPosted: Sat Aug 29, 2009 4:04 pm    Post subject: Reply with quote

fireBALL,

you could always buy a v3 from the robotfuzz webshop

http://www.robotfuzz.com/OSv3

cheers
_________________
http://www.headfuzz.co.uk/
http://www.robotfuzz.co.uk/
Back to top
View user's profile Send private message Send e-mail Visit poster's website Yahoo Messenger MSN Messenger
FireBALL



Joined: 24 Jul 2009
Posts: 28

PostPosted: Sat Aug 29, 2009 4:35 pm    Post subject: Reply with quote

Cheers Ginge

any plans of introducing new ones with incremental encoder support? It would be a great idea to have an option of resetting '0' position

OT - have a look at this, might be a good replacement for pots. It's a miniature absolute encoder by Usdigital, and should not be difficult to fit inside a servo

Code:
http://usdigital.com/products/encoders/absolute/rotary/shaft/ma3/
Back to top
View user's profile Send private message
jharvey
co-admin


Joined: 15 Mar 2009
Posts: 359
Location: Maine USA

PostPosted: Mon Aug 31, 2009 8:59 am    Post subject: Reply with quote

That is a nice device, unfortunately I don't see how it could be used in a RC servo. Most servos have either a D shaft or two flats on the shaft. It appears you can get this with a couple different diameters, but can't get it with flats.

$36/ea is also interesting.
Back to top
View user's profile Send private message Visit poster's website
FireBALL



Joined: 24 Jul 2009
Posts: 28

PostPosted: Mon Aug 31, 2009 9:51 am    Post subject: Reply with quote

I tried dremel with a grinding stone on a precision solid steel rod and was able to get the right flat surface.

Once I receive my encoders I'm going to do the same on them, will post a picture if I manage to do it.
Back to top
View user's profile Send private message
jharvey
co-admin


Joined: 15 Mar 2009
Posts: 359
Location: Maine USA

PostPosted: Mon Aug 31, 2009 4:11 pm    Post subject: Reply with quote

Do you know what the shaft is made of? Looks like it might be the magnetic materail. If so you might want to take some precautions. Grinding magnetic materail can cause magnetic dust that is known for some nasty issues when air born. I think it was mostly the Colbalt, but I forget what the issues are exactly. With luck, it will turn out to be steel or something pleasant to modify.

Keep us posted.
Back to top
View user's profile Send private message Visit poster's website
FireBALL



Joined: 24 Jul 2009
Posts: 28

PostPosted: Tue Sep 01, 2009 4:20 am    Post subject: Reply with quote

That's a good thought but it can't be magnetic, that will lead to other kind of operational and manufacturing problems.

In any case I'm going to write to them and ask.

thank you for the input. much appreciated.

Ginge*** any possibilities of early christmas this year? (any discounts on 3 OpenServo V3 boards)

cheers


Last edited by FireBALL on Tue Sep 01, 2009 9:07 am; edited 1 time in total
Back to top
View user's profile Send private message
ginge
Site Admin


Joined: 14 Jan 2006
Posts: 1031
Location: Manchester, UK

PostPosted: Tue Sep 01, 2009 8:14 am    Post subject: Reply with quote

Quote:
Ginge*** any possibilities of early christmas this year? (any discounts on 3 OpenServo V3 boards)


lol. Maybe. I already reduced the price to near cut throat levels, but I will see what I can do.
_________________
http://www.headfuzz.co.uk/
http://www.robotfuzz.co.uk/
Back to top
View user's profile Send private message Send e-mail Visit poster's website Yahoo Messenger MSN Messenger
FireBALL



Joined: 24 Jul 2009
Posts: 28

PostPosted: Tue Sep 01, 2009 8:16 am    Post subject: Reply with quote

Quote:
but I will see what I can do.


Cheers Ginge
Back to top
View user's profile Send private message
FireBALL



Joined: 24 Jul 2009
Posts: 28

PostPosted: Wed Sep 23, 2009 12:32 pm    Post subject: Reply with quote

ginge >> I ordered one yesterday but didn't get any confirmation after paypal routine, hope it's all ok and the board is on it's way Smile

cheers
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    OpenServo.com Forum Index -> Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group