Questions about past email and other things [TANKS]

[Rodolphe GREMEAUX <r.gremeaux-at-wanadoo.fr>]

Title:

Hello,

i've some question about this email
   

	Most current tanks use about 4 inch diameter drive
	sprockets turning at about 400 rpm.  That produces
	4.76 mph.  I estimate that you need about 400 in-lbf
	sprocket torque per track to perform a full skid turn.

here is there a link between 400rpm and 400in-lbf to make a full skid turn ?
By the way is the total weight of the tank is inclueded ? Is it 120 pounds ?

Also a thing i don't get about the specs : 
the spec of the EV warrior are at 12V
Stall torque : 691 in-oz
Peak HorsePower : 0.38 hp

The mini EV motor are :
Stall torque : 64.64 in-oz
peak ph -at-12v : 0.313 hp

How could the stall torque on one motor be ten times biger than the other motor and 
how peak horse power could be kind of the same.

An other thing, could we underpower a motor:
if i try to make working a 24V dewalt motor at only 12v?
Will it work? if yes how good ?

Also, is it the shortest diameter sprocket wheel where should be connected the motor 
or the longuest sprocket wheels ?

Regards.

Byron,

At 04:22 PM 2/21/2005 +1300, Byron <klingemeister-at-gmail.com> wrote:
 > I was going to use the Tyng Track System driven by 2 Mini-EV motors
 > (see http://www.robotcombat.com/marketplace_motorsmisc.html) attached
 > to the drive wheel by a bike chain

Most current tanks use about 4 inch diameter drive
sprockets turning at about 400 rpm.  That produces
4.76 mph.  I estimate that you need about 400 in-lbf
sprocket torque per track to perform a full skid turn.

Using a 45:1 reduction on the Mini-EV motors to reduce
18000 rpm to 400 rpm, increases torque from 4.04 in-lbf
(64.64 in-oz) to 182 in-lbf.

It appears that you would need two Mini-EV motors per
track (and two 45:1 reducers per track) to provide sufficient
sprocket torque.

At 05:29 PM 2/21/2005 +1030, "chris barthelson" <barthelson88-at-hotmail.com> 
wrote:
 > You could try the "EV-X" motors from www.surpluscenter.com they are
 > only $16.95 and the shiping is pretty reasonable. you could also have a
 > look at this site http://www.oatleyelectronics.com/motors.html they have
 > very good prices on a few different motors and they would only have to ship
 > from Australia.

The SC300 24V 300W scooter motors from Oatley ($36 Aus) are the same
ones that I tested for my post on Feb 9 2005
http://www.rctankcombat.com/archive/current/msg00156.html

Oatley's motor SC250G ($79 Aus) looks particularly promising. Although it
is more expensive, it already has a gear reducer built into it.

Both of these motors are manufactured by Unite Electric Motors
http://www.unitemotor.com/ with part numbers MY1016 and
MY1018slowdown respectively.  Unfortunately, I have not been
able to find a vendor in the US who carries the MY1018slowdown.

At 06:47 PM 2/21/2005 +1300, Byron <klingemeister-at-gmail.com> wrote:
>Also, How many channels does it require to run an Anvilus or Tri pact
>speed contorller?

two channels

Both speed controllers perform right-left mixing to use one
joystick for driving.

At 09:25 PM 2/21/2005 +1300, Byron <klingemeister-at-gmail.com> wrote:
>How would the paintball gun elevation and firing work, could theu
>possibly be combined into one channel?

They could be combined but it would be very difficult to do.

I recommend buying a five or six channel radio.
2 ch for tracks
1 ch for turret rotate
1 ch for gun elevate
1 ch for trigger

You can use a 4 channel radio for a tank destroyer
with no turret.

Joe


**********************************************
Joe Sommer, Anvilus Machine Works
2378 Nantucket Circle, State College, PA 16803
814.234.4773     anvilus9-at-adelphia.net
http://www.anvilus.com