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[DPRG] On contests

Subject: [DPRG] On contests
From: dpa dpa at io.isem.smu.edu
Date: Thu May 31 15:05:44 CDT 2007


Interesting post, Chris.  A couple of comments.

I believe that you have built several nifty robots, two that I know of for
sure, to pursue your vision project.  So in that sense you fall outside
the set of folks that only seem to build in response to a contest challenge.
You are a "self-starter" as the HR folks like to say.  As are many others
in the DPRG.

Robotics is, as you detail below, a multi-disciplinary field.  That's its
difficulty and also its appeal.  The query was not so much the generic
difficulty and cost of building robots as much as the apparent need in the
DPRG for a "steady flow of contests," with all the attendant logistical problems,
in order for robots to be built at all.  That clearly does not apply to you
and a number of others.

I guess I'd like to see us go to maybe just one big contest per year, with
the work load spread across the membership.  That's how the SRS club does 
it, and their events are great, lots going on, vendors, demos, workshops,
lots of different sorts of contests and participants, and a year to prepare.

Along the same lines, I have a very nice wooden and brass plaque that I won
six years ago at the SRS Robothon (2nd place "Floor Exercises") hanging on
the wall in my shop, which I really like.  I'd like to hear some discussion
about going towards that sort of symbolic award for our contests.  I know it
will cost the club money, but I think we have the money, and that sort of
award has a class and a permanence that technology awards and paper certificates

A final comment about money.  We all know people whose hobby is sailboating
or dirtbikes or R/C planes, snowmobiles, scuba diving, stamp collecting, ham
radio, whatever, that routinely sink thousands of dollars into their hobby.
Somehow in robotics we're suppose to do everything on the cheap.  I guess
it's really a question of motivation.  We'll do it if it's not too much
trouble... But I don't know any robot builders (well, maybe a few) who
spend the kind of money on their hobby that skydivers spend on theirs.  I'm
not sure the money argument is not really a motivation argument.  

(Actually, the way I do it is when my wife wants some new furniture or
whatever, I say "yes dear" and take the opportunity to buy a fancy sensor
or some nice motors or hardware or something.  YMMV)


> Ed Okerson)
> >Speaking for myself, I find it hard to get excited about the contests
> >anymore.  The outdoor events are interesting, and I would love to compete
> >in one of those, but there just isn't enough time in the day to get an
> >entrant ready.
> (David P. Anderson)
> >> We've had this discussion on and off over the years, and the conventional
> >> wisdom has always been that the membership just won't build robots without
> >> contests as an incentive.
> >>
> >> Now I'm probably a peculiar deviant from this wisdom.  My problem has
> >> usually been the opposite --- that there are no contests designed to
> >> show off what my robots are built to do.
> (Chris Jang)
> As a new guy and oddball in the DPRG, I believe the main reason why there
> are not more robots is simple economics. They are incredibly expensive to
> develop. I think it is comparable to writing computer games. It takes so
> much work and requires such a breadth of knowledge and experience that
> even small teams fail to finish in a reasonable time frame.
> Part of the expense is hardware. A capable field robot will not be cheap.
> The vehicle must be rugged and somewhat powerful. It will cost hundreds
> of dollars. Computers and sensors will be several times the cost of the
> vehicle. This tends to push the cost up into the low thousands of dollars.
> I have seen others do things inexpensively as I too have. But I think this
> path leads often to a low ceiling on capability. I'm not saying it is bad
> to go cheap. I think it is good. It avoids costly development and mistakes
> before acquiring enough experience to design a "production" vehicle (which
> will be expensive).
> The other major expense is software development which can always become a
> bottomless pit if it goes wrong. And most amateur builders did not study
> robot programming in school. Robot software is not like any other kind of
> software I have ever encountered. It becomes its own specialty rather much
> like computer games. Design and programming patterns arise from the
> intended application.
> The last expense is theory. This is the single greatest expense for me.
> After about a year of abortive software development and reading - I think
> I see where image processing ends and stochastic inference begins. But I'm
> only at the point of knowing - what I don't know, what I don't need to
> know and what I do need to know. So I study, write code, and learn.
> And if you are like me, then you had to teach yourself electronics before
> even starting any of this! This took me literally 6 to 12 months before I
> had even a basic intuitive grasp. It is out of the question for someone
> who doesn't have much free time.
> Yes, I think that if a robot is designed for a specific contest, then it
> can be done more economically. But when people face the significant
> investment of time and love in a hobby, they want to make something
> interesting to them and special. So they then build different robots that
> intrigue them. A side effect is that they cost more and may be suboptimal
> for any particular contest.
> jBot is a very shrewdly designed machine - 6 wheels using RC components
> with odometry, GPS/IMU and SONAR for obstacle avoidance. The computer is
> a microcontroller. The only thing missing (excuse me David, my recollection
> of a conversation we had last year may be inaccurate) is that the Kalman
> filter does not incorporate odometry readings into the process model. But
> otherwise, it is pretty close to optimal selection of technologies for what
> it does - much like the GPS/IMU with odometry and LIDAR for SLAM augmented
> with camera video is an optimal solution for a DARPA Grand Challenge style
> race (e.g. Stanley the VW Touareg).
> Most people, myself included, have never progressed far enough to be so
> shrewd about design. Or perhaps we have other interests. I do observe there
> is often a natural convergence of design for any given set of requirements.
> Given outdoor waypoint contests, most robots will be 4 to 6 wheeled or
> tracked EOD (e.g. packbot) sized machines with GPS and odometry.
> Anyway, that is why I think there are few robots. Building them is costly
> in many ways. It requires significant investment of time, money and
> education. I believe it is really much like building your own airplane or
> writing a large computer game. It can take years.

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