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SRS Meeting: February 19, 2000. 

Renton Technical College, Room J314.



President:  Ted Griebling       erich@erich.seanet.com
VP/treasurer:  Ron Provine      ronprovine@telesphere.com
Secretary:  Tom Dickens         thomas.p.dickens@boeing.com

New people today?  About about ten.  Welcome!  Attendance is about 60
plus.

Doug: March 18 (normal SRS meeting day) at 1:00 will be the NW Fire-Fighting contest.   There are about 5 or 6 robots ready for this.  We have prizes for the top placing robots.  It should be a fun event!

Frank: Little e-cam, $59 from Fred Meyer.  CMOS, 24-bit color, 160x120.
Serial interface.  From Vetco, nice set of boxes.

Paul: Puyallup Hamfest on March 11, 9am.  There is a $6 entry fee.
Electronic junk galore!!!  http://www.njqrp.org there is a link to a
palm-top PC, cheap, hackable(?).  New Jersey QRP.

Ron: Showed off the current state of his modified toy-robot system.
This is based on the RAD1.0, by ToyMax (now have version 2.0).  The
robot has a pair of arms, tracks (5 wheels each), bends at the waist,
and it shoots missiles.  The brain he added is a 8052-type board.  Very
nice!

Mark: There is a big robot exhibit at the Portland museum.  Latest
venture is making a new face for an anamatronics robot.  Got a book from
Tap Plastics on molding.  He developed a vacuum forming system (plaster
mold, homemade vacuum table to a shop-vac, the kitchen oven).  He walked
through the process, and had excellent examples.

Ron: Still have a few Robothon-1999 T-shirts.  Ron has done a class for
University Prep grade school, building a line-following robot.  ATMEL
2313 processor (pre-programmed by Ron), small DC motors, motor drivers,
IR detectors, etc. 

Tom: Tapping and dyes.  Using Dyes for threading motor shafts.  Can then
tap the wheels, or use nuts.  He's looking at using the disks from
mini-disks.

Marvin: Wheels, urethane.  See http://www.monstermakers.com for other
ideas.  Brought in an O'Riley book "the unofficial guide to Lego
Mindstorms".  Also brought in a GameBoy programmer (commercial, GB X
Changer MGD3) http://www.interstateggames.com, a programmer with
cartridges.  Very easy to program.  Recommends the movie "Fast, Cheap,
and Out of Control".  Very entertaining!  Also brought in a storage
oscilloscope.  Small HW device (free), SW (demo) is free for 2-ports.
$49 4 channels, max 460 samples per second.  See  http://www.dataq.com.
Lastly, he showed a temperature probe system.  The small probe records
temperatures once a minute continuously.  It can then download its data
to a PC and the data plotted.  www.ibutton.com.   Other interesting
products, but they are slow to ship due to demand. 

Allen: Vecto has some 40x40 displays.  Also, Parallax programmer.

Karl: Current version of M-BOT, a small robot which he will use as a
common platform.  3 circuit boards-  68HC11 with PSB813 chip for memory
expansion, a custom motor driver board for DC motors and IR wheel
encoders, and a 1-amp switching power supply ($8 complete, the simple
switcher, http://www.national.com look under evaluation boards).  Karl
has 3 of the motor boards for sale and wants feedback from them to make
a product. 
Karl will be taking orders for his new book "Build Your Own Robot".  See
Karl, he will bring in the books next meeting.

Anne: haven't been around for over a year.  Has taken a job at NASA (was
with Newton Labs).  Working on Mars rover, the next version of
Sojourner.  Larger, more capabilities.  About 2-feet tall, as wide as a
door, quite heavy.  It has a Pentium processor board with SCSI, IDE,
serial ports, running at 7.5 watts.  The idea is to run indefinitely
using solar panels.  Trying to have the full electronics running at 15
watts.  Uses a 68HC11 board for power control (30 to 40 power switches)
to manage all on-board power.  It planning a JPL test in the desert, May
18-19 this year.  Programming languages are LISP, C, Perl.  Running
Linux on board.  68HC11 board programmed in BASIC and assembly.

Ivar: Brought in a hex-pod walking robot, home built.  68HC11 BOTBoard
brain, programmed with SBASIC, 12 servos.  Will be adding turning and
sensors.  He wants help with PIC serial communications.  Very cool!

Gene: Aluminum castings.  Ron and Gene successfully made a number of
castings.  Experienced trying to melt some very hard Boeing aluminum,
too mush slag, etc.  Learned a lot.  They plan to build a system for
Ron, which Gene will document.  Meeting in Port Orchard, Sunday after
SRS meeting, 10-12.  Contact Gene for information.
gene@harbornet.com    (253) 858-9105.

Bill: Several robot sumo events.  OMSI (Portland) April 15.  NW Sumo,
May 20 in Edmonds.  Millennium Games (Calgary) June 9-11.  He is aiming
at the All Japan Sumo in Japan, December 23.  See
http://www.sinerobotics.com/sumo

Gary: Picture of how NOT to wire a 68HC11 system.  Hand wired, no board,
etc.  Worked, but not pretty.

Ted: Doing some looking into motors.  Speed of the motor is proportional
to the voltage. 

W = k V
W is radians per second
V is voltage
k is a constant (RAD/S/Volt)
T = - 1/k I
T is torque (Nm)
I is current
k is a constant (Amp/Nm)

Can spin a motor with a drill, measure the RPM and the resulting
voltage, determine k.
Now, this k can be used to determine the torque (T).
Conversions to work the equations:
2PiRad/revolution
142 Oz. In / Nm


Great meeting, see you at GodFathers...