BORIS
This version has been in existence for over 20 years in total although not
in its current format, this is an ongoing long term project and is therefore
constantly being revised.
The main 'brain' of this first version was a veroboarded Z80 8K computer
which powers various onboard circuits including speech which uses an SP0256
speech system. It provides self contained computer control, or, alternativley,
an on board video camera which enables a remote operator to drive him via
a 172 MHZ telemetry link, using a 6402 UART, and a commercial 2.4GHZ microwave
video transmission system using a joystick and video monitor. This'vision'
system also has a stereo hearing capability with twin electret microphones
being used as ears!
Power is in the form of a 15Ah 12V sealed lead acid battery which powers
all of BORIS'S systems including the motors to drive him. The motors are manfucatured
by a firm called Klaxon and originally would have been used to power an electric
wheelchair, the plastic ABS wheels with rubber tyres are from a local hardware
store and are sited to the rear of the chassis with front mobility being obtained
through a castor wheel.
The ability of speech means that BORIS can tell you when he has hit something,
when he is stuck somewhere and should you forget to recharge him - he will
ask for you to "help me....I am dying"!
Boris upgrade
BORIS has is currently undergoing a major upgrade:
-
A new custom welded chassis has been put together by a
local metal fabrication company
-
New motors (salvaged from a light duty electric wheelchair)
have now superseded the old windscreen wiper motors - for vastly improved
performance
-
A new fully electronic motor control circuit has now replaced
the original arrangement of changeover relays, using a L6203 motor control
chip, directly driving each motor, giving TTL level logic control directly,
PWM speed control, and electronic braking
-
Better wheels with rubber tyres from a local hardware
superstore have replaced the hard plastic ones
-
A new computer based on Arizona Microchip's 16F877 40
pin micro controller, retaining the familiar SPO256 speech synthesiser,
and original allophone developed speech is under construction, as the 8K
flash based '877 is far easier to program than the EPROM based technology
I used with the Z80 based computer
-
A new remote telemetry system operating in the 70CM Ham
band, using proprietary RF modules, and Holtek data encoders/decoders have
replaced the clumsy UART based system
-
A smart grey ABS case has replaced the old steel drawer
that formed BORIS's original body, giving a very good standard of weather
protection
-
The video transmission system now uses a Maplin 2.4GHZ
video TX module, and a proprietary receiver board from G1MFG electronics.
BORIS is now up and running in remote telemetry mode, and has considerably
improved performance, and awaits his new brain.
-
Proprietary 70cm radio receiver (Radiometrix) and 12 bit data decoder, forming high grade radio control
-
23CM TV transmitter from Radio Communications Lab (India)
23CM PA based on RA18H1213G hybrid module - up to around
5W (limited by heatsink) RF output, giving a range of several KM.
Improved radio TX (Radiometrix) giving 100MW at 70CM and a potential range of over 1KM
USB to radio controller – originally developed with Holtek encoder/decoder pair, now awaiting upgrade to 12 bit encoder/decoder chip (due originally to a problem with rx immunity to the 23cm tx, this was solved by moving to the high grade Radiometrix rx/tx pair, but the data output from these modules proved unreliable with the Holtek chips, despite a great deal of trial and error). The eventual aim of this is for controlling BORIS over the Internet.
PIC based Morse code sender, using the audio subcarrier of the tv tx, to provide compliance with the UK amateur radio regulation.
