Drive system

[ACEGUY]

Much like in the featherweight, would the propedrive motors work in a HW? if they can which ones should I look into?

[maddox10]

If you want to replace a 3 kg motor (Bosch 750) with a 600 gram motor (propdrive 5060) you'll need more of'm.
Also, smaller motors run faster (the slowest propdrive is 270 KV, 2 times faster than the Bosch 750)

In short, if you want to have the equivalent of a "bosch 750" drive in propdrives 5060 you want at least 4 of'm, and be prepared for a higher gearratio.

[ACEGUY]

One other thing I was wondering would any of the following in the link below work in a HW or MW?

http://hobby.npcrobotics.com/store/p...tor-gear-kits/

I know NPC T64 are the way to go but, I'm looking at other options as well.

[maddox10]

The NPC-02446 motor is advertised as "great" for lightweights.

The data from Robot Marketplace gives this motor a 500W rating.
You can get a heavy moving with those, but you won't be happy with the results.
If you want any acceleration, you'll have to use a gearratio of 6-7 to 1 with the 4" wheel. Trundling around @10kph. But you'll be there in a jiffi.

[shakesc]

Have a look at what Ellis did with Sandstorm - good example
http://king-of-bots.wikia.com/wiki/Sandstorm

[ACEGUY]

Have a look at what Ellis did with Sandstorm - good example
http://king-of-bots.wikia.com/wiki/Sandstorm

Maybe I didn't notice but, what motors did he use in Sandstorm?

[maddox10]

BIG brushless, with heaping piles of power. Not some weedy 500W wheelchair motors.

I guess something like the Rotomax 80CC or bigger.


Bananaking, a Russian machine, uses Revolt motors, and because decent Brushless controlers for this kind of power ain't common (MGM Compro is one of the few commercial options at €800+ a pop) he went with Euans 300A VESC's (see that thread). Another thing were Ellis is involved with.

[shakesc]

On Sandstorm its a really small package for a heavy
They are Maytechs either 50 or 63mm cans - one per wheel and a low ratio, something like 4.4 : 1
There is a write up somewhere, maybe instagram

[maddox10]

So, 4 motors . As I stated at the start of this topic.
If I combine the data I can find easely on Sandstorm,
24mph(almost 40kph)
4-1 gearratio
Guess on 5" wheels.
Maytech 50 or 63mm motors.

I guess the Maytech MTO5065 170 HA-C is the lightest option. 1800W+ each. 7Kw of drivepower. Sounds a bit like 37V powered Bosch 750's or equivalents.

With 1 size bigger, the MTO6355 170 HA-C that power about doubles per motor. Giving the very nice 14Kw...
Not 1 kw of the NPC drive proposed in this thread.

[shakesc]

Found the link

https://www.facebook.com/ellis.ware....78749245527646

By all reports its physically small for a heavy

[maddox10]

Yes, and that is the advantage of brushless outrunners. More efficient, and if chosen well, not that expensive per Kw on the wheels.

The days of £1000 for 5Kw are gone.