[chbot] Meeting Report Wed 16 June 2010

[Richard Jones]

Meeting Report Wed 16 June 2010

Sixteen people attended and the collection raised $17 for which
Science Alive will be very gratefully received. Our next meeting will
be on Wednesday 21st July 2010 in the Science Alive Seminar Room. I
have a fancy screwdriver that was left in the room, and King has
misplaced a laptop power lead. Please get in touch via the mailing
list if you can help get these back to their owners.

Mark suggested we move to monthly meetings and a majority thought this
was a good idea. Science Alive have agreed and the room is available
for the remainder of the year, so we now meet on the 3rd Wednesday of
every month.

Kay showed us incredible jointed moving models of dragon, cat,
trebuchet, and a remote controlled model Roman Galley. Constructed
from scratch many using his home made electric scroll saw, and
intricate carving. Must be seen to be appreciated.

Peter brought along the MKII lawn mower prototype electronics and a
huge motor platform on which they run. Now based on ATMega328, state
machines drawn in Dia and auto generated code, FET Motor control, with
HM6532 compass module. The platform wiggled across the room nicely on
a set bearing. Peter also mentioned that it is very good at turning
towards large metal filing cabinets. I think it should be called Luke
as it uses the force.

Robin spoke about his 32 channel automatic watering system hosted on a
Linksys WRT54G wireless router running openwrt. The system is web
controlled using json objects delivered to a browser that overlays
control rectangles over a satellite image of the property for the gui
control interface. The web server uses open source
http://code.google.com/p/mongoose/ which readily integrates the
control function calls. The same json file delivered to the browser is
also used in the server to associate the 1 wire IC addresses with the
active areas on the gui. The water solenoid valves are controlled
using 70c triacs, driven by 1 wire chips that interface to the wrt54
via a serial to 1 wire converter avoiding the need to write kernel
drivers. A current transformer protects the well pump by shutting down
the system if the water solenoids are not drawing the appropriate
power demanded by the system.

Sachin presented his work using genetic algorithms. He showed a
demonstration of a genetic algorithm approach to generating a
photographic image using ascii art. Then a demo of using genetic
algorithms to evolve a player for the  open source game Tenix. Each
solution was iteratively refined using a fitness score, mutations were
found to be counter productive above 0.5%. Eventually Sachin wants to
teach his crab hexapod to learn how to move using the  genetic
algorithm approach. Sachin has posted his open source projects on
Google code here: http://code.google.com/p/neural-network-classes/ and
here http://code.google.com/p/tennix/

Charles brought along his half size Dalek to be used at a wedding in
February. Charles spoke about the journey towards making the Dalek
involving glues and PVA not setting when sandwiched between
polystyrene, completing his CNC machine, a vacuum forming jig that we
saw last time, and different paint and shape choices. The Dalek is
looking very impressive.

Thanks to all those who came and especially those who presented their work.

Our next meeting will be on Wednesday 21st July at 6.30pm.

Photos here : http://picasaweb.google.com/113134050398543502524/ChchRobotics16June2010?feat=directlink