IGR

Zero2 Microrobot

@13 October 2015 -web # Quick Guide to using Zero2
User Manual
Robotics on the QL - David Buckley Robotics on the QL 1 Quanta magazine
Robotics on the QL 2 Quanta magazine
Robotics on the QL 3 Quanta magazine Feb/Mar 2007
Article for Maplin Magazine 1985 - circuit explanation - David Buckley - [revised 22 January 2007]
Maplin Magazine, March May 1985 - David Buckley - [revised 22 January 2007]
Maplin Magazine, June August 1985 - interfacing - Dave Goodman
Assembly Instructions - Colin Freestone
# Power requirements
# Programing
# Programing Model - see Maplin Article for larger diagrams
# Spectrum BBC interface
# Spectrum/QL/PC-serial interface circuit
# PC-serial interface photos
# Motor Wiring
# Motor and Speaker Cables
# Add-Ons
Zero2 software Sinclair QL SuperBASIC control program - David Buckley
#Sinclair Spectrum #ZeroDrive Z80 code for Spectrum LOGO/BASIC - Richard Moyle #BBC-B
#Research Machines 480Z
#IBM-PC
Data Sheets folder view
80C97=HEF40097B.txt
HEF40097B.PDF
HCF40106.pdf
HEF40106.pdf
IM6402.PDF
IM6402[2].PDF
MC14584.pdf
MC14584=HCF40106.txt
TIL32.pdf
TIL32[2].pdf
TIL32-Texas.jpg
TIL78.PDF
TIL78-Texas.jpg
TIL81-etc.jpg
TIL81-etc.PDF
TIL81-Texas-1.jpg
TIL81-Texas-2.jpg
ULN2001.pdf
Z2-Motors.jpg
ID31-farnell23919.pdf - stepper motor
ID31-1.jpg - stepper motor
ID31-2.jpg
ID31-3.jpg
ID31-4.jpg
Proposed embeded Software-Utilities
Miscellaneous
# Proposed Game
# Proposed Trailer Lift
# Spectrum RS232 4800 baud accuracy
Development of Zeaker2 and Zero2
UK Design Registration #Register Entry
#Zero2 drawings
#Certificate
History 1983 August - IGR - Inter Galactic Robots Ltd - incorporated.
1984 June - Zero2 designed.
1985 14th February - Press Launch of Zero2 at the Institution of Mechanical Engineers, 1 Birdcage Walk, London.
1985 April - production of Zero2 started.
1986 - Starting in First Quarter industrial action by teachers severely affected sales,
1986 6 November - IGR ceased trading.
1987 16 February - Statutory Meeting of Creditors.

Quick Guide to using Zero2

Power requirements
12 volt 1 amp supply for the motors
5 volt at ~150mA for the electronics

The original power supply, 9V 12.6VA, gave 14v off load and 9v on load, and the original interface had a 5v regulator to supply the electronics, see the interface diagrams.

Using an original Zero2 PSU
Zero2 total current 870mA @ 9.75v
Zero2 electronics only, 130mA @ 12.9v

Programming
Setup Zero2 as in the photograph and connect to a computer Serial port through a suitable interface, see the interface diagrams.
Zero2 responds to character codes sent at 4800 baud, no parity, and 2 stop bits.
Each time a motor code is sent the motors will step to their next position, if codes are sent out of sequence then the motors will just judder.
When driving the motors a small delay must be inserted after each character to give time for the motor to turn. When Zero2 was conceived time delays generally were not necessary because the computers were not too fast. If a delay can't be inserted then sending the same character several times will have the same effect. In fact the QL software supplied with Zero2 did just that.

Sending the codes  5, 0,10,15  makes Zero2 go forwards four 0.5mm steps
Sending the codes  5, 0,10,15  again makes Zero2 go forwards another four steps
Sending the codes  5, 0,       will make Zero2 go forwards another two steps
Sending the codes       10,15  will make Zero2 go forwards another two steps

Sending the codes 10, 0, 5,15 makes Zero2 go backwards four 0.5mm steps Sending the codes 10, 0, 5,15 again makes Zero2 go backwards another four steps Sending the codes 10, 0 will make Zero2 go backwards another two steps Sending the codes 5,15 will make Zero2 go backwards another two steps

similarly Sending the codes 6, 0, 9,15 makes Zero2 turn right four 1 degree steps Sending the codes 9, 0, 6,15 makes Zero2 turn left four 1 degree steps and Sending the codes 7, 3,11,15 makes Zero2 turn right two degrees only the left wheel moves four 0.5 degree steps Sending the codes 13,12,14,15 makes Zero2 turn left two degrees only the right wheel moves four 0.5 degree steps

You will note that all the sequences have been arranged to end on 15 so no matter what the next sequence is that is sent it will continue on without missing any steps.
By sending individual codes in the correct sequence Zero2 can be made to move in 0.5mm steps
and turn through 0.5 degree (only one wheel is moved).

for detailed information see the Manual Chapter 4 - Writing to Zero2

Programming Model



Spectrum BBC interface

Spectrum/QL/PC-serial interface circuit

PC-serial interface 2006


The umbilical for Zero2 uses Sinclair QL serial connectors, similar to BT phone connectors but left-handed and with 'W' style polarisation.
Ordinary ribbon cable can be used with them by stripping the ends and lightly touching the ends with solder to make them easier to insert in the plugs, there are holes just to the end of the contacts so you can see the cores going to each contact, make sure a core goes to each contact before pressing down the contacts.



Parts:
6-way W-polarisation socket
3.5mm jack socket for standard Zero2 9v 1A 12.6VA PSU (14v off load)
5v 1A 7805 regulator
1A In4001 diode
2x 0u1 disc ceramic
100u 6v
green LED
220R resistor
9pin D R/A socket
The Four way header [1:0v][2:--][3:Tx][4:Rx] in the bottom right is to connect the interface to to a Parallax Stamp board, [1:0v][2:--][3:Rx][4:Tx]
and the three way header is my standard serial header [1:Rx][2:0v][3:Tx].

Motor Wiring

Motor and Speaker Cables

Add-Ons

A lifter and pallets to allow Zero2 to do a horezontal Towers of Hanoi. The pallets were stacked in a line rather than the normal way of stacking rings vertically. The vertical column is fixed in place of the pen.
This is similar to the proposed Trailor-Lift.