Just to get my 2 cents in...

Based on my experience Ron is right on with all the stuff below; but
especially about the batteries, fan and the UV photodiodes.

I have no experience with the ultrasonics and the fancy candle sensors
yet. :)

On thing he (and the acroname folks) dont point out is that you really
need a maze of your own or you have no way of reliably testing your
machinery and wall avoidance stuff. I build my porta-maze from 1/2"
foamcore and it works well enough.

Make sure you test in as many mazes as possible though! That's the best
way to get your bugs out in the open. Martin probably has the most
robust entry in our area now that his 'bot has been in a few competitions.

Also, get used to fixing your bot away from your comfortable workbench.
When your assumptions (or your 'bot!) get broken you will want to fix
it rather than give up and go home. Having the tools handy is a big
plus to start with, but just being able to thing under pressure with
piles of distractions around you is a challenge in itself.

The March break event (March 1 to 16!) at the Museum of Science and
Technology will be an excellent preperation event for your 'bot and its
support system (hint, hint, nudge, nudge) as well as a decent deadline
for getting the thing working in time.

Remember, the Trinity contest is the weekend of April 13! That's only 4
months of building time away!

Albert.

Ron Clough wrote:
> Bill,
>
> Here's my take on the Acroname information:
>
> NiMH batteries - thumbs up. Forget NiCad; they'll soon go the way of
> the Dodo. NiMH has all the advantages of NiCad plus no memory effect
> and more mAHr per gram.
>
> Ultrasonics - thumbs down. Too many reflections in the confined
> space of the fire fighting arena.
>
> UVtron - thumbs up. Expensive, but when it "says" there's a candle
> in this room, you better believe it!
>
> GP2D12 - thumbs up. Motorola microcontrollers (jab, jab) can run
> their ADC's in continuous scan mode in the background. You just read
> a result register when you want a reading.
>
> Eltec - thumbs up. Very effective at pinpointing the location of a
> candle.
>
> Use a fan - thumbs up. It really is the simplest and most effective
> way to blow out the candle. Other methods are impressive to watch,
> but, in my opinion, not worth the effort.
>
> Compass - a big thumbs down. The magnetic field is not as "clean" as
> one would like.
>
> Probably the best piece of advice that I got from a fellow hobby
> robotist somewhere in the internet was "Check your batteries
> frequently". When things start to go wrong and you're scatching your
> head, its probably the batteries.
>
> Now, in defense of my "overkill" micro from Motorola . . .
> 16 ADC's sounds like a lot. Here's how I'm using them:
> 6 Sharp range finders: front, back, frontLeft, frontRight, backLeft,
> backRight for navigation and wall avoidance.
> 1 Eltec PIR to pinpoint the candle's location.
> 9 UV phototransistors to know approximately where to candle is
> located.
> For navigation, the Sharp sensor ADC's will run in continuous scan
> mode in the background. When needed, the UV phototransistor and
> Eltec ADC's will run the same.
> 256K FLASH sounds like a lot. It currently is, but its nice not to
> have to worry about running out of memory!
>
> The 9 UV phototransistors may be overkill, but I really should have
> had them last April in Hartford! My robot found the room that had
> the candle (UVtron). It then rotated to pinpoint the candle using
> the Eltec PIR. However, it rotated the wrong way, ie. the long way
> around and wasted several seconds finding the candle. If it had
> rotated the other way it would have found the candle in less than a
> second! It won't happen this coming April!!!
>
> Cheers,
> RonC
>
> --- In ORE_bits@yahoogroups.com, Bill Wright <wrightw@a...> wrote:
> > Ron:
> > The fire fighter sounds, if you will excuse the expression, so
> > complicated. I am a first timer (actually a wantabe) so I am
> looking for
> > information, particularly of the beginner nature. I found the site
> > below to be useful. Is it, however, accurate?
> > http://www.acroname.com/robotics/info/articles/trinity/trinity.html
> > I would welcome additions, deletions, or general thoughts from a
> variety
> > of people on this if it is possible. I would like to write specs
> before
> > I start designing and this is the most I have as a starting point.
> > Bill