Re: To Joe [TANKS]

["Trevor Vickers" <tkv000-at-gmail.com>]

Joe, 

I have a few questions on ESC's, I'm looking at either the IFI Victors 885's or the Vantec RDFR33, I know its not scale, but I want to be able to turn my tank by one motor forward and one motor backward spin. Would you happen to know if the IFI Victors do this style? I'm a little green here and from there website specs I gather that they will do one motor forward or reverse, so I would need either one Vantec or 2 victors...

On 3/6/06, Joe Sommer <anvilus9-at-adelphia.net> wrote:

Marc,

At 03:21 PM 3/6/2006 +0100, "Marc en Wendy" <marcmethorst-at-zonnet.nl> wrote:
> > Can I plug 2 ESC's (assuming you mean Electronic Speed Controllers)
> directly in the rx and connect them to the motors, and set the mixing on
> the tx? Would this make a proportional controlling system?
>
>Pete C. replied that it would.
>
>Since I'm thinking of building a low budget second tank I was wondering
>what would be the difference between the above mentioned set up and the
>Anvilus controller set up?
>I understand that I need ESC's that can handle the amps, but apart from that?

My relay SSR controller does three functions.
1)  provides right-left mixing for single joystick operation (on-board PIC)
2)  provides forward-off-reverse for each motor (on-board relays)
3)  provides proportional speed control for each motor (off-board SSRs)

You can use elevon mixing in your radio for 1) and two ESCs
can do 2) and 3).

However there are two problems.

a)  In my opinion, the only reliable reversible ESCs in our
voltage/current range are IFI Victors 884 (40 A, $115),
883 (60 A, $150) and 885 (120 A, $200).
http://www.ifirobotics.com/

I recently bought a 100/60 A reversible ESC (eBay item 6038132557)
for evaluation but it has not yet arrived.  They cost about $25
in QTY=10 (eBay item 6039817396).  I will post how they work.

Other tankers may recommend other reversible ESCs.

b)  Elevon mixing usually only provides 70% speed for both motors
when the stick is straight forward or reverse, or when the stick is
hard right or hard left.  It provides 100% speed for one motor in the
corners of stick travel.

If you want to use separate ESCs, I recommend using the IMX-1
mixer ($40) from Robot Logic   http://www.robotlogic.com/product_imx1.html .

These are my recommendations -
Roboteq AX1500 = $275 = 30 A per track proportional with mixing
Roboteq AX3500 = $395 = 60 A per track proportional with mixing
Roboteq AX2550 = $495 = 120 A per track proportional with mixing
two IFI Victor 884s and IMX-1 = $270 = 40 A per track proportional with mixing
two IFI Victor 883s and IMX-1 = $340 = 60 A per track proportional with mixing
Robot Solutions RS80D = $275 = 80 A per track proportional with mixing
Anvilus relay SSR and two D1D40s = $150 = 40 A per track proportional with
mixing
Anvilus relay SSR = $100 = 40 A per track forward/off/reverse with mixing
Anvilus mini relay = $25 plus relays = 40 A per track forward/off/reverse
with mixing

Vantecs   http://www.vantec.com/   are popular with combat robot builders.

The RS80D from Robot Solutions
http://robot-solutions.com/RS1/product_info.php?products_id=29
has worked very well for Steve Tyng.

Joe


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