June 1995

AHRC Atlanta Hobby Robot Club
REAL Robot Experimenter Amateur League
June 24th 1995 Meeting notes.

The meeting was started by John W. Gutmann at 9:15 am.
John handed out the PARTS list for 1995. This is a list
of parts recommended by other hobby robot builders on the
internet as useful for building a hobby robot.
Next John showed a video tape of "Roberta the Robot"
a senior class project at Dekalb Technical Institute
in Atlanta GA.

Bill Moffitt showed a robot he built for the Hartford Conn.
fire fighting contest he entered this month. The contest was held
at Trinity College. Bill described where he got the parts and how
he built the robot.

Bill also told us about the contest and the interesting way in
which students solved the problem of finding and extinguishing a
burning candle flame.

The 3 of our AHRC members entered the junior division and got
3rd place. Congratulations.....
One guy built a robot that used a catapult to throw baking
soda to smother the flame. There was this big cloud when it
went off. It was not very fast though.

Another one was called the "Weasel" it had a long balloon that
was held out in front and when the balloon got over the candle
it burst from the heat and blew the flame out.
Bill works for an elevator company and used some of the parts
that are used in running a elevator.
Not one elevator part was used on the robot that the students
built. Bill was surprised.

Ringo Davis brought the magazine, called "Robotics Practitioner"
and showed it to everyone. A couple of people wrote the name
and address down, so they could get a copy.
Next Paul Hudson gave a 15 minute presentation on the HERO jr.
and gave to everyone a 4 page handout showing major parts of the
schematic in block diagram. Paul had made copies of the
schematic and reviewed some of the functions.
He talked about the basic mechanics. Power supply, computer,
key pad, sensors, and drive motors.
The way they tell when a robot is moving they use a optical
encoder on the wheels.

For sensing he has a infrared sensor, and a ultrasonic sensor
like the one used in Polaroid camera. And finally a light sensor.
Paul popped the covers off and showed the CPU board and the driver
board that acts as an interface. It uses 4 transistors that
drive a stepper motor, small speaker that acts as a microphone,
and a large speaker for the speech output.

There is a RS232 connector to allow upload and down load of programs.
Paul showed us the demo routine, and had HERO jr. sing songs.
This hero has 10k of ROM memory. Hero counted hand claps.
Paul for 5 years used to fix Xerox copiers.

Charles Redwine demonstrated a chopper circuit he built for a
mobile base in order to reduced the amount of effective power
to the drive motors. The mobile base moved much smoother
than if it was driven by straight unchopped 12 volts.
Finally we took a short break and drank coffee and hot cider,
provided by Charles Redwine.

After the break Charles spent several minutes describing to new
visitors how the binary system works and how to convert to

At around 11:30 the meeting broke up and Ringo Davis went out to
his car and brought in the aluminum frame he is currently working
on. The design is a 6 legged walking robot, modeled after the
robot shown in "The Robot Builders Bonanza"book. We were all
impressed his progress so far. John Gutmann asked why he didn't
bring it in sooner and Ringos reply was "It is only half done".
"I have heard this said more than once!" John said..... I wish
you had told us before the meeting.

We all went out into the parking lot and took some photos of the
robot and some of the people who attended the meeting.....
Next months theme is TOOLS. Bring in to the meeting the tools
you use to build hobby robots.

Edited by John W. Gutmann
__ _ _ _ _ John W. Gutmann - SYSOP - Robots R4U BBS - 404-978-7300
|__) |__| | | john.gutm...@robot4u.atl.ga.us Member of R.E.A.L.
| \ | |__| ROBOT HOBBY; The Complete Manual for Individuals and Clubs
Voice 404-972-7082 Ans Machine - FAX 404-979-3660,,,,11

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