Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: srgalli on November 02, 2009, 10:47:35 PM

Title: 6v power source for servo driven robot
Post by: srgalli on November 02, 2009, 10:47:35 PM
I am currently building an Arduino Duemilanove based robot with servo driven differential steering. I am using a protoshield and a motor shield stacked on eachother. I have ordered two GWS continuous rotation servos to use, and I would like to run them on a full 6V separate from the microcontroller. I am looking for a cheap Nimh pack and charger (already over budget) and a way to hook it into the pins on the motorshield or at least a way to connect it to the servo. This is my first non BEAM robot build and I am pretty lost. Any ideas on hardware would be appreciated. Peace.
Title: Re: 6v power source for servo driven robot
Post by: SmAsH on November 02, 2009, 11:20:00 PM
A few quick questions:
Well, do you have any values for mAh that you are looking for?
There are hundreds of packs i can suggest but i need you to narrow it down a bit...
What would you call cheap? $20? $40? $60?
Title: Re: 6v power source for servo driven robot
Post by: srgalli on November 03, 2009, 11:16:23 AM
To be honest I don't really know what mAh I desire. I have seen 2000 mAh for around 10 bucks but I don't know: A. what charger to use with them B. how to attach them to the pins in the servo connector that is connected to the controller.
I am only driving two GWS servos with this battery driving a set of tamiya track and wheel treads.
Ideally, I'd like to spend less than 40 dollars on a battery/charger combo. Already sunk 220 in parts on a $200 budget.
Title: Re: 6v power source for servo driven robot
Post by: SmAsH on November 03, 2009, 01:49:58 PM
$30 for both, and a really good charger at that!
http://www.all-battery.com/smartuniversalchargerfornimhbatterypack24v-72v.aspx (http://www.all-battery.com/smartuniversalchargerfornimhbatterypack24v-72v.aspx)
http://www.all-battery.com/6v2000mahnimhreceiverbatterypackwithtabsforairplane.aspx (http://www.all-battery.com/6v2000mahnimhreceiverbatterypackwithtabsforairplane.aspx)
Your going to run the electronics off a separate battery right?
Title: Re: 6v power source for servo driven robot
Post by: Webbot on November 03, 2009, 01:52:55 PM
See if you can find something like these:
http://www.vapextech.co.uk/acatalog/copy_of_High_Power_Model_Control_Batteries.html (http://www.vapextech.co.uk/acatalog/copy_of_High_Power_Model_Control_Batteries.html)

The page shows a suitable charger as well. More mAh = more bucks.

I like these because they come with the 'chunky' Tamiya connector (as used on R/C cars) as well as a Futaba connector (just like a servo connector so it plugs onto header pins).
Note that there is no power switch - so if you would need to hook up your own one.

Try searching on Amazon or eBay as there often deals to be had
Title: Re: 6v power source for servo driven robot
Post by: srgalli on November 03, 2009, 03:51:54 PM
This is the shield that I am hooking the servos to in the upper left corner. The online help says to cut the 5v trace to the servo pins and attach my battery to that. How would I go about doing that? there is only soldered nubs on the bottom side of the board. As well, would this battery be acceptable?

http://www.megabatteries.com/item_details2.asp?id=13676&cat_id=153&uid=1310 (http://www.megabatteries.com/item_details2.asp?id=13676&cat_id=153&uid=1310)



(http://www.ladyada.net/images/mshield/done.jpg)