All the requests we receive for equipment are potentially one-off specials. We
will discuss with you your requirements with your proposed set up and basic
methods to achieve this. The majority of requests can be fulfilled with our
standard product range. Each one of course is adjusted to provide the right
frequencies and range of options to suit your order.
However, some requirements will need a special design. These will be discussed
in further detail to reach a specification which will be quoted for. Hopefully
this will be within your budget or alterations to the specification may take
place to bring it within your budget. There are some examples below and further
ones described (link).
Other examples of our work, methods and capabilities can be found on our
Consultancy pages of this web site, Buckman Hardy
Associates. We all operate out of the same building, AWR being the name for
our direct sales of astronomy products.
A page describing what we can do in this area. Having supplied motors and designed
electronics to the National Physical Laboratory in the UK we are in a position to
speak from experience. Goto our page on AUTOMATING A DOME.
See below for the entry on the NPL dome and shutter.
HIGH POWER MICROSTEP SYSTEM FOR
SHEFFIELD UNIVERSITY 24" (April 99)
We have fitted a rack mounted Microstep Drive system to drive two size 34 Stepper Motors
already fitted to the Sheffield University 24 inch Cassegrain reflector. This
involved customising the Microstep software to provide two frequency generators (rather
than driving in Microsteps) for the two axes. We managed to achieve 8500 steps per
second max drive rates. Further customising involved controlling clutches to select a high speed slew.
The Intelligent Handset is being fitted soon. This telescope is a monster, constructed by
the Royal Observatory, Edinburgh. They have a large website describing the observatory,
its history and performance, it is worth looking at.
HIGH SPEED DRIVE BOX FOR LARGE CUSTOM TELESCOPE (April 96)
Special high speed requirement using our STEP3 motors up to 2200 steps per
second in slew. A constant current Chopper Drive Board was bought in to satisfy
this requirement. This technique retains high torque from the motor across the
speed range. The accelerating slew provided by our SYSTEM 5 handset was used
as the hand controller.
Whilst the chopper drive board was in our building we tried it on some of our
motors. We reached 9000 steps per second (unloaded) on our STEP5 motor. This was
demonstrated at some exhibitions we attended.
VERY HIGH POWER DUAL SYNCHRONOUS MOTOR SYSTEM (Aug 96)
INSTALLED AT THE NORMAN LOCKYER OBSERVATORY ON THE MACLEAN TELESCOPE
A synchronous motor drive system with the following power ratings: RA Slo-Syn
motor 120V 40 Watts, DEC 24V 20 Watts. Each axis has a +/- 20% variability in
common with other synchronous motor designs. On test the design was capable of
suppplying 80 watts of power to the RA motor. This is quartz crystal locked for
Sidereal rate with VFO option fitted and relays to supply the two phases
of the declination motor. The handset is based on the SYSTEM 5 product.
The drive box converts the TTL frequencies for the two axes to a power output.
An 8th order digital filter provided a SINE wave of reasonable purity which was
then fed into an amplifier driving a transformer. Balancing the output was quite
tricky to avoid a steady DC current flowing which reduces the effectiveness of
the transformer and dissipates extra heat in the drive transistors.
The DEC was based around our standard inverter which is a pseudo square wave
drive, although no transformer was used. The supply rail of 24V DC was switched one
way round then off for 1/8 cycle then switched the other way round then finally
off for 1/8 cycle. The end result with some capacitive smoothing is a basic
sine wave but with a high harmonic content.
AUTOMATED DOME FOR NATIONAL PHYSICS LABORATORY (February 95)
In conjunction with Beacon Hill telescopes we provided electronics and motors
to open a shutter on a 2 metre dome and rotate a platform on which some
scientific equipment now rests. The assembly is operated from the room below.
The position of the platform is indicated on a panel.
Completely remote operation was achieved. Sensors were used around the periphery
of a Beacon Hill 14 inch worm wheel and the platform was moved one segment at a time.
The equipment on the platform automatically acquired its target and tracked it for
the duration of that segment. When the platform reached the last sensor a fast rewind
was provided using accelerating slews.