Why are there two different power inputs on the Servotor? Do they both need to be powered up to run Hexy? In my trial attempt the other night all I managed to achieve were spasms, and that was with just the Servo power connector plugged in.
No problems installing Python/etc. I think the firmware was updated to 1.5 okay. Win7 32-bit laptop if that makes any difference?
Any suggestions?
Thanks in advance,
Toni
Never mind - found the answer in previous posts. 
TTFN
Toni
By the way, a two-cell Lithium Iron Phosphate (LiFePO) battery pack is nominally 6.6V, versus 7.4V for Lithium Polymer, and seems to be working fine for my Hexy.
Something like this would work: hobbyking.com/hobbyking/stor … Pack_.html
HTH
Toni
That’s really very close to / slighty over the max voltage for those kind of servo’s you know…
Also note that , while 6v gives more torque than 5v ,it also means the servo’s dissipate more heat with 6v, which might not be the best idea for this application where the servo’s might need to work quite lot .
so please let us know if this works out for you in the long run
Agreed, this is cutting it close. I think toni was planning on building a much improved (and expensive) version herself anyway, so maybe she just wants to push it to the limit and see what it can do 
I’d like an opinion on using a SBEC…
my thinking is that I could reduce weight nicely with a LiFe or LiPo battery, and use the SBEC to make sure I don’t fry my hexy servos.
thoughts?
I don’t have that one,but another (old) 5V 4A ubec (just tested for fun) and that is a no go, to much voltage fluctuation if you move more than 3 servo’s at the same time…
if servo’s start you basically have a (very short time) a relatively huge draw, so with complex moves I doubt a 5A ubec will be enough for 10 or so servo’s
note that that this is a totally different property than the “constant rating of 5A and a surge of 7a for 15 second”.
You need a 5V source that is able to deliver a (rather huge) spike of power without dropping the voltage.
I would assume the “linear” is better for hexy, for 2 reasons:
), which is normally faster to deliver some short bursts of “oumph” than the “feedback loop/switching” type who constantly adjust (very fast, 10 to 100khz normally) the voltage outputted.i’ve ordered
hobbyking.com/hobbyking/stor … EC_8_.html
a 8A linear BEC
and
hobbyking.com/hobbyking/stor … ipoly.html
a 8A switching DC-DC regulator
to test what those cheapo’s give (if they work you can’t make one you’re own for the price and even if they don’t work in hexy i can use them )
Joseph said Arcbotics are also testing Ubec’s some so I expect him to be able to give some info one of these day’s about ubec’s.
Of course it may be that that model is good enough and i’m going for overkill…
edit: from a review on HK:
"The description of this switching BEC is misleading. It will supply 3A continuous, but the output voltage drops off at any current draw higher than 3 amps. The ripple voltage is also extremely high compared to others and what would be expected from a power supply of this nature. The heat created is also unacceptable. Power hungry servos like the HXT900 (at 500mA each) would stress this BEC if using 6 servos. The only good thing is the ability to handle 6 cells. "
so i would not buy this for hexy
I’ve lost three servos at this point, so I’ve put Hexy to one side until I can order replacement gears from ArcBotics, but the 2S LiFePO worked well for a good few hours so far. I’ll need to order a couple of extra Servotors too.
I also tried a UBEC, but 5A was not enough juice for complex movements, hence switching to the LiFePO for full current capability.
I’m planning on remaking Hexy in aluminium and titanium, using 4.4kg-cm torque metal servos, split over two Servotors to spread the amperage, slap an arduino board in front of the Servotors reading PWM signals from an R/C receiver, and mount a large hammer on top - Combat-Hexy
teamradicus.com/page/Hexapedal-Hitman.aspx
TTFN
Toni
[quote=“tonifowlie”]I’ve lost three servos at this point, so I’ve put Hexy to one side until I can order replacement gears from ArcBotics, but the 2S LiFePO worked well for a good few hours so far. I’ll need to order a couple of extra Servotors too.
I also tried a UBEC, but 5A was not enough juice for complex movements, hence switching to the LiFePO for full current capability.
I’m planning on remaking Hexy in aluminium and titanium, using 4.4kg-cm torque metal servos, split over two Servotors to spread the amperage, slap an arduino board in front of the Servotors reading PWM signals from an R/C receiver, and mount a large hammer on top - Combat-Hexy
teamradicus.com/page/Hexapedal-Hitman.aspx
TTFN
Toni[/quote]
Bookmarking your site. That sounds like a blast!