Re: (ET) Go Cart power alternative

["Christopher Meier" <mr23 mn rr com>]

This year's B*E*S*T entries included a design by the Sartell, MN kids
that was inspired by the Segway legislation passed in many states, allowing
self balancing 2 wheelers to go anywhere pedestrians can legally. Not
only did these 4-6 grader's complete a working design, but they raced
it, and completed the endurance race (as well as the slalom and drag
races) without a hitch.  As I counted the endurance race laps off, each
time the vehicle went by, the driver had a big smile... not all the teams
can say that, as some of the cars can be a bit hairy to drive.

The pictures from 2003 are not yet up on the website, so check back
over the next few weeks to see what this vehicle looked like.

-Chris

----- Original Message ----- 
From: "Jim Coate" <jbc coate org>
To: "Elec-Trak List" <elec-trak cosmos phy tufts edu>
Cc: <solidtech qwest net>
Sent: Tuesday, May 20, 2003 3:33 AM
Subject: Re: (ET) Go Cart power alternative


> Excellent idea! You didn't say how much "older" the kids are, but one
> example in the 5th & 6th grade range is the B*E*S*T program that Lee
> talks about on the EV list from time to time - it sounds like the kids
> really get into it (http://www.bestoutreach.com/). Or if they are a bit
> older can look at "electrathons" for inspiration & component ideas.
>
> A few thoughts on parts... First, please don't use Sam's Club or any
> other flooded batteries - use *sealed* batteries. If and when the cart
> gets tipped over, you don't want acid to be spilling. AGM batteries,
> like the Hawkers that Chirs Z has been enjoying, would be a top notch
> choice, but more than you may need, depending on age of kids and
> speed/acceleration desired. Gel-cell batteries don't dish up the same
> type of currents but would still do well for reasonable speeds - and are
> much more common being used in UPSs and wheelchairs. You may find a
> battery dealer, computer department, etc. with used but still good ones
> they'd be happy to donate.
>
> Second, make sure the set up includes an appropriate fuse or breaker -
> rated for DC use. Might also start with a very low current limit until
> the bugs are worked out and then go to a slightly bigger size.
>
> As for the motor, an E15/E20 motor strikes me as being on the big/heavy
> side. Also having the separate field winding makes finding a controller
> harder and one more thing to hook up right. If you had some ET motors
> just sitting around, then may as well us it. But if seeking out
> something from scratch, a somewhat smaller permanent magnet motor would
> do nicely.
>
> For the controller, could either use a simple contactor setup (like the
> ET) or an electronic controller. The EV suppliers sell a 'gas pedal'
> with the variable resistor inside to connect to the controller.
>
> Some high school kids I know in upstate NY built an electric go-kart
> (and "Greased Lightning" car for their schools' performance of "Grease!"
> :-) I'll see if I can find the info on where the motor/controller came
> from as it sounded like a good deal.
>
>
> Solid Technologies wrote:
> >
> > All,
> >   I work with Royal Rangers at a local church here in Colorado Springs
(I
> > mostly work with the 7-year-old Ranger Kids).  I was talking with the
> > Outpost Senior Commander this evening and found out about a new
older-boy
> > program for Saturday evenings that involves go carts - building them
from a
> > pile of parts.  Well, I mentioned that we should have (at least) one
that
> > uses electic power vs. an ICE (quieter, less maintenance, etc.).  So,
the
> > request for the group is specifying and tracking down an appropriate
> > configuration.  My initial thoughts are:
> >   Motor: From an E-15/E-20 (where can I get one?)
> >   Contoller: I think I've seen someone selling one (who/where?)
> >   Speed pedal: Spring loaded gas pedal linked to a variable resistor?
> >   Batteries: Maybe a set from the local Sam's Club (or maybe a set of 3
___
> > that I've seen a couple of notes on).  Or maybe a set of 4 @ 12V for
more
> > speed?
> >   Charger: I have a spare 36V, but if we go 48V then what?
> >
> > Input please.
> >
> > Thanks,
> > --joe
>
>
> _________
> Jim Coate
> 1992 Chevy S-10
> 1970s Elec-Trak E20
> http://www.eeevee.com
>