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DPRG: Sbasic , gambling , and probability

Subject: DPRG: Sbasic , gambling , and probability
From: Corey Hansen nzhansen at ihug.co.nz
Date: Sat Jan 10 18:06:58 CST 1998

Hi,

Alright here's the thing:

I'm building a robot that will learn , or at least I hope it will. To do
this I am attempting it with Sbasic. My plan is to have a simple
platform;wood , wheels , motors , caster , batteries , brain , and some
stray electronics. The brain is HC11 based. The robot , for now , will have
8 inputs , 3 IR , 4 bumper switches , and a Cds cell set to be tripped at a
certain light level. The motors will be driven by a classic H-bridge.

OK , there are 8 inputs , which can be represented by a one byte wide
variable. Since there are 256 different combinations of sensor input , there
will be 256 different situations for the robot to learn what is best to do.
To know what is best to do , the robot needs a goal , which will be to stay
away from things. To learn the robot needs to experiment , and have some
randomness , mixed with probability. To do this all of the combinations have
7 variables to represent motor output. What the robot needs to have is a
number of effectiveness inside each variable , to start say 128.

The robot needs to choose which of the motor outputs to use , according to
probability and randomness. For this to work the robot needs to stage a
'gambling' effect with the motor outputs. At the start all the variables
have 128 probability of being chosen , here's where randomness is needed. I
need the robot to choose which output would work best by experience.
Whichever output is chosen must be tested for effectiveness. After the
output is executed the robot needs to wait for the inputs to change , when
they do it needs to determine if more sensors went on or off. Since the goal
is avoiding things , the lower the byte wide variable
representing inputs is , the better , or vice versa. Now that it has
determined if that move was a good or bad , the robot needs to change the 7
variables. If the move was good , then the robot needs to add 1 to the
variable representing the move , and minus 1 from the rest. Now the cycle
repeats.

What I'm having a problem with is 'gambling' for the right motor output ,
while pay attention to the necessary probability. If anyone would like to
help it would be greatly appreciated.

:David
davehansen at geocities.com

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