Thomas Schmidt

Tea O Matic is a little helper to pull out tea colander, egg or sac, when the tea brewing time is over. Controled by a computer program it finishes tea brewing just in time - automatically.

the problem

teaOmatic/start.jpg Unfortunately its not posible to have always a eye for my brewing tea. Sometimes the telephone rings, sometimes somebody has his problems with something i don't want to think about ... or simply the complete server farm blinks red in my network monitoring tool. In the past a lot of forgotten teas where inedible :-(

the first solution

teaOmatic/ teaOmatic/wmTea.clock.jpg The first solution was the wmTea program. It creates a little icon with a tea pot, a clock and a brewing time end signal. But the problem was: How do You pull out the tea colander by hand when You're in trouble with some broken network connections ?!

the enhanced solution

teaOmatic/vorn.jpg The idear to build a little electrical actuator was very old. In the past i thought on new parts, but with the "Mach flott den Schrott" (german: means: refloat the scrap ) competition of the german computer magazine Ct' (the goal was to build something complete new from computer scrap) i started to think about using broken things out of computers. teaOmatic/hinten.jpg The result is an actutator build from a broken CDROM drive (it wasn't possible anymore to read CDs with), an old AT PC-power supply and a lot of other computer scrap. The controler was implemented with a PIC16F628 from Microchip and a MAX 232 driver to handle the RS232 interface for communication with wmTea. I removed the CDROM drive's Laser and the electronic for CD reading (that speeds up initializing the drive), teaOmatic/schematic.jpg - simply the loader mechanics and the electronic for the loader button & motor where still present after modification. The power supply was an old AT one without any use in modern computers - so the PIC controller, the MAX 232 the CDROM motor and every left electronic was supplied by this power supply. Additionaly the supply was used as stand. teaOmatic/board.jpg The controler unit is soldert on a single sided circuit board. Next to the PIC and MAX 232 is also a optocoupler, some indicator lights and 2 function buttons. Position of coleander holder is taken over two magnet field detechtion HAL sensors.The communication is like the AT instructionset also known from a lot of MoDem devices. Implemented is the logic with some PIC-assembler commands.

The RS232 terminal command set:

ATDTstart brewing sequence - colander holder goes downX
ATZend brewing sequence - with shakingX
ATXZend bewing sequence - without shaking X
ATRS nread out sensors
ATWA nset an actor n
ATSTAwrite out status to RS232X
ATVwrite out complete startup messageX

the result in picture and video