## Programming Help?

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• My task is to program a robot to slalom around two different colored cups. The cups are blue and yellow, but which is in front and which is in back is a
Message 1 of 2 , Apr 24, 2006
My task is to program a robot to slalom around two different colored
cups. The cups are blue and yellow, but which is in front and which
is in back is a variable. I am having trouble coding this problem
with Java. Anyone have any good programming ideas on how to tackle
this problem?
• First, you need to be more specific in the algorithm. You ve written one that a human can understand. But you are trying to get a bot to understand it and it
Message 2 of 2 , Apr 25, 2006
First, you need to be more specific in the algorithm. You've written one
that a human can understand. But you are trying to get a bot to
understand it and it won't. What I have my students do is an exercise
called "Be the Bot". The student is required to implement the algorithm
using only the sensors and motors that the bot has. I usually have the
kids get up and walk around the room using touch sensors (hands) and
motors (legs) to implement a maze runner algorithm. This gives them a
much better understanding of what a bot can and cannot do. It also makes
them write much more precise algorithms.

Second, you need to be more precise in your description of the problem
and the bot. How many cups are there, just two or more? If only two is
the bot supposed to do a figure 8 or just pass between them? How far
apart are the cups? Are the cups marked in some way so the bot can tell
how far around the cup it's gone? Can the bot touch the cups or not?
Does it have touch sensors or Sharp GPs or an SRF04 or 08? Is its light
sensor short range or is it like a CMUcam where it can see colors at a
distance? Does the bot have navigation aides, like a GyroPAK or a
compass, or distance measurement abilities? Etc.

My point here is simple: once you carefully define the algorithm, the
programming is usually pretty obvious. And always remember, on your
first attempt your objective is not to be elegant or optimal. Your
objective is to get the d@mn thing to work.

Just so you won't think I'm being too theoretical, here's a behavior
in low to high priority are goForward (default), goAround and foundNext
(highest priority). goForward simply goes forward and, hopefully, one of
the higher priority behaviors will find the cone. goAround navigates the
bot around a found cone. foundNext looks for a cone of the opposite
color and, once it finds it, moves the bot towards it until the previous
cone is lost from sight. Obviously, this is only a starting point for

wjr

fantizmoe wrote:
> My task is to program a robot to slalom around two different colored
> cups. The cups are blue and yellow, but which is in front and which
> is in back is a variable. I am having trouble coding this problem
> with Java. Anyone have any good programming ideas on how to tackle
> this problem?
>
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