New Hexy power source

Post on my site.

hexythehexapod.com/index.php … wer-source

Nice! I also have been using LiPo’s and haven’t gone back to NiMH since. These are cool because you can get them to charge faster with the right charger. I get my 850mAh batteries to charge in about 25-35 mins at 2C.

I’ve been using this guy, I’ve liked it because it has a built in volt meter (4 leds, all on for “battery full”) and a convenient power switch:

http://www.hobbyking.com/hobbyking/store/__6233__TURNIGY_8_15A_UBEC_for_Lipoly.html

It’s worth mentioning that if you go down the LiPo route, you are going to want to get a good charger and power supply. Also… educate yourself about LiPo safety:

http://www.youtube.com/watch?v=ixIOEPnsgbI

:wink:

TooManySecrets, what does your UBEC to Hexy connection look like? I’m plugging mine into only the servo power… my UBEC has 2 power outputs, but I only had a connector for one of them.

Im at work currently, il post a pic as soon as i get home.

I’ve ordered the same UBEC show in the link http://www.hexythehexapod.com/index.php/blog/27-new-hexy-power-source

I’m not sure I know the best lipo to go for though? Anybody have any suggestions?

The links says 7.4v is a better choice than 11.1v…

But what is the best amperage? Is it the more amps the better for powering the servos?

But there’s a tradeoff if a battery too big and heavy that would be bad right?

On ebay I see 7.4v at various mAh up to about 5200mah…

Pinged TooManySecrets on the side - hoping he or others might advize on the best 7.4v lipo options to use with that ubec…

FWIW I already have a couple 11.4v parrot ar drone batteries, but they are only 1000ma…

I’m guessing their current is too low for the the hexy servos, even with this ubec dropping the voltage to 5v?

Again my biggest doubt is if I buy a 7.4v lipo just for hexy, should I be going for the most current I can find at 7.4v, or could I hurt the hexy doing that? i.e. Is the more current the better for the servo power or is that wrong thinking?

It’s only semi related, but I’m also planning to use my raspberry pi with the hexy and it also requires 5v, but only 750ma.

Ideally I was hoping to run the pi and the servos off the ubec output from a single battery.

BI’m not sure if the pi will only draw the smaller amount of current that it needs (compared to the servos), or (again) whether I could actually damage the raspberry pi if the current is too high?

i.e. Is damage normally a result of voltage that’s too high, or can it also be cause if current is too high? (sorry probably a dumb question I’m just pretty green when it comes to this stuff)

Thanks a million for any tips,

Darren

Well i have tried a lot of liPos by now and it seams a 1000 mAh one would work for you , it just wont last that long. Also the UBEC limits the ammout of current going to your servos. For the Ubec im using its 5 Amps and for short periods of time it can go 7 Amps. So no worry there.

The more mAh your lipo has the longer it will last before you have to charge it.

But really why are you still thinking about this. Lipos are dirt cheap these day. Even those really cheap ones are good. I have been using a lipo that i got for really cheap of Ebay for a year now and no problems.

Just remember to charge them in a lipo bag or under a cooking pot :slight_smile:

Thanks too many secrets that helps a lot I didn’t realize the lower current batteries would work for the servos at all.

Based on what you said I’m thinking the 11.4v/1000mAh ar drone batteries I already have may be worth a try after all.

If I can drive both the servos and the raspberry pi off one of those that would be ideal.

I confess I only was “still thinking about this” because I don’t know what I’m doing. :slight_smile:

I was esp. concerned about doing the wrong thing and ruining the Servotor32 board or the raspberry pi board.

So thanks,

Darren

To be clear (if someone as dumb as me reads this later) I mean a would try the 11.4v/1000mAh ar drone batteries with the UBEC which drops them to 5v.

What is your AR drone version that you are using?