Harold by Tony Mercer

Harold is a 3 axis pick and place robot built from an old record
turntable (used for the waist) 3 stepper motors, 1 geared DC motor,
2 DPDT relays with a contact rating suitable for the DC motor,
thin sheet metal and wood, assorted toothed belts and hobby type gear
wheels, string, rubber bands, etc. It uses a simple PC 
(286 to 486. There may be timing problems with a Pentium) with a
parallel printer port, a mouse (must be able to run under
DOS) VGA, 12V power supply (car battery perhaps) and 2 stepper motor 
driver boards. These boards were described in the January 1994 edition
of Silicon Chip, an Australian hobby electronics magazine. The
software  needed was described in the same magazine of November
1995. The software is basically to control stepper motors, 4 solenoids
and to react to 4 sense lines and as such could be used for other 
purposes (automatically controlled telescopes, etc.) However the
software has been written for an educational and hobby purpose and the
author would be reluctant to support it in a critical commercial
environment. The software has been written using Visual Basic for DOS
and all functions and controlls are accessed using a graphical user
Costs: The software is available from NewTech Education Resources for
$50 Australian but a shareware version can be downloaded free of
charge. The kit of parts for a stepper driver is also available
from NewTech for $39 Australian. A flat ribbon cable with appropriate
connectors to join the driver boards to the PC is available at $16
Australian . Other pricing details including post and packing are 
included in the software.
However both versions of the  software contain a readme
file that includes details of the electronics required for those who
want to roll their own. The other costs associated with the project
are mainly to do with what ever reources you have at your disposal ie.
mechanical and construction abilities and access to the usual hobby
builders supplies.   
The registered version of the software inludes a 54 page manual that
describes the software, construction details for an example robot,
and a tutorial. 
Tony Mercer tonmer@erebus.hie.unimelb.edu.au

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