Design Dilemma

[Eventorizon]

Re: Design Dilemma

I will have 2 GR-1 motors (Got them today ), 2x 30A electronize ESC's, 1x 40A Electronize ESC, 1x Speed 900, 2x Technobots Blue wheels, then probably a linear actuator to act as a shrimech and flipper, and I am looking into getting lipols onsteda of my NiMH's so combine that with loosing 2 motors and 10cm of body work it should all fit in

[Laser]

Re: Design Dilemma

1x 40A Electronize ESC, 1x Speed 900

If the 40a speedo was for the speed 900 I would get a bigger speedo to be on the safe side e.g victor 883

2x Technobots Blue wheels

What are they? Do you mean robo challenge or banebots?

[Eventorizon]

Re: Design Dilemma

Done it again, the Robochallenge blue wheels and yeah the 40A ESC was for the Speed 900BB, will it definately blow cos I have already ordered it!

[Laser]

Re: Design Dilemma

well most people who use speed 900's use victors.
as its a spinner your motor will stall if you have a low ratio and hit another robot, so its just to be on the safe side soo you dont blow the speedo.
another way to get round this is to put a fuse in so you dont blow the speedo, and blow the fuse instead

[Eventorizon]

Re: Design Dilemma

I was going to go for a 4:1 ratio with speed 900 so the disc will spin at about 1400RPM, is that enough of a drop?

I was also going to fit a massive heat sink if that will make a difference...

[Laser]

Re: Design Dilemma

I have no experience with spinners but that sounds a good ratio.

[Laser]

Re: Design Dilemma

What voltage will you run the speed 900 at?

[ewan]

Re: Design Dilemma

I'd say the Electronize will be fine if you're careful not to stall the motor too much. 40A is the /continuous/ current rating and a speed 900 at 12V has a stall current of 54A, obviously more at 14.4 or 18.5V but should still be within the controller's peak ability. And 4:1 is actually rather a high reduction

[Eventorizon]

Re: Design Dilemma

Its currently 14.4V with my 2 NiHM packs but If i get a LiPol it will be slightly higher than that, the motor is rated up to 24V so I should be ok, fingers crossed, and could I get away with 3:1?

[razerdave]

Re: Design Dilemma

I believe Drumroll uses a 3:1 ratio on his drum.

[ewan]

Re: Design Dilemma

3:1 should be fine. I'd recommend a 18.5V Li-Po
Also remembered what the first CAD reminded me of, an American machine called Manta: http://www.youtube.com/watch?v=a1mr7fpxqt0

[jonny]

Re: Design Dilemma

the electronixe will probably be fine, if it blows just replace it with a battleswitch and 100 amp solid relay. i run 2 speed 900s of one of them

[teamshock]

Re: Design Dilemma

If I were you I would run the speed 900 at around 24v and use either a 4:1 or 3:1 ratio on the disc and either use the solid state or Automotive relays (70A ones work well).

[Eventorizon]

Re: Design Dilemma

How do you go about boosting the power up from 18V to 24V. I know its somem kind of transformer (A couple of my flat mates had to get a mains Cree LED running of 2 AA batteries )

[MikeNCR]

Re: Design Dilemma

How do you go about boosting the power up from 18V to 24V. I know its somem kind of transformer (A couple of my flat mates had to get a mains Cree LED running of 2 AA batteries )

Generally, that would just be buying a 6-7 cell pack instead of a 5 cell pack depending on the exact voltage you wanted.