Technical Focus Sound of Music, Sightline

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Sightline Summer 2007
Technical Focus
The Sound of Music
Over 80 ABTT and
ALD members
visited the London
Palladium to take
a detailed look at
the staging of
The Sound of
Music
Stage Technologies make the ‘hills come
alive’ in the new production of The Sound
of Music at the London Palladium, literally
move a mountain which is one of the focal
pieces of scenery in this highly acclaimed
production in London’s West End. Mark Agar
from Stage Technologies and production stage
manager Jo Miles hosted the visit. The scenery
movement was demonstrated in real show
time, without actors but with lighting cues.
The interest was very much focused on how
it moved and looked.
The most spectacular was the disc for the
Alps, which flies in and vertically turns while
covering the whole stage. Stage Technologies
worked with set building company Scena to
create this scenic piece which is lowered from
the grid and has to rotate along horizontal
axes, all of which is controlled by an Acrobat
control console.
Left: BT 200 winches fixed
to counterweight frame
Right: Stage tower showing
the Mountain haulage chain
and control and power
cables.
The flown Mountain is a multi-axis scenic
piece weighing approximately eight tonnes.
The movement of each axis has had to be
carefully considered in how it affects the
other two and the relationship between the
Mountain and its surrounding scenery. There
is a Servomotor and Mayr electromagnetic
brake on the input shaft of the gearbox and
two electromagnetic brakes on the output shaft
of the gearbox. The motor/gearbox drives a
heavy duty chain which is double-purchased
top and bottom around the gimbals to which
the Mountain is attached.
The rotating component of the flown
Mountain motor is attached directly to the
input shaft of the gearbox, with dual-caliper
hydraulic disk brakes on the output shaft of
the gearbox. The motor and gearbox are
contained within the stage-left gimbal and
travel with the Mountain.
Installed within the Mountain piece are
foldback speakers and scenic gravestones
which rise up to provide a dramatic visual
effect.
The whole Mountain is suspended on two
towers positioned either side of the stage. This
loading exceeded the Palladium stage’s safe
working load. Concerned engineers decided
to prop up the underside of the stage to the
concrete floor below, which took the weight.
No one dared ask how far below is the Central
tube line!
As well as beautiful mountain backdrops,
the story of the problematic Maria unfolds
amidst the stone walls of an abbey and the
beautiful Von Trapp family mansion house.
Large automated trucks bring the house onto
stage in four sections. The synchronisation
and millimetre positioning of these trucks is
vital to bring each piece together in full view
of the audience.
Stage manager Jo Miles told members that
there was “some intake of breath for the first
few runs but the system soon settled down…
as confidence grew. Positional stops are few
and show stops – hardly ever.” Occasionally
dirt in the tracks causes a bit of trouble – so
sucking up the dirt is an important job; if not
done properly it would stall thousands of
pounds’ worth of machinery.
Onboard drive systems enable each truck
to rotate, turning the sections to transform the
interior into the exterior in fast fluid moves,
Sightline Summer 2007
achieved by each having a Servomotor
attached directly to the input shaft of the
gearbox. The output shaft drives a rackand-pinion slew ring. With the drive cabinets
located on board the truck, they are fed by
power from Profibus and switched at 24Vdc
via a cable reeler and slip ring assembly which
enables simultaneous endless rotation and
tracking.
Big Tow winches are used to fly wall
backdrops onstage to create the abbey and a
bedroom where the children take refuge from a
thunderstorm. Cloths, gauze and banners are
pulled into position and life size birch trees fly
and track into view all done by the Big Tow.
The Big Tow winch is a multi-purpose
scenery-moving winch, which will lift loads of
up to 500 kg at speeds of up to 3 m/s. The Big
Tow winch incorporates patented ‘zero fleet’
technology which ensures that the take off
point for the cable on the drum remains static.
This allows the winch to be easily mounted in
any position without the concerns of fleet angle
normally associated with drum winches.
The Big Tows operate virtually silently, do
not suffer from vibration and can be used as a
point hoist, counterweight assist, power flying
winch, a performer-flying winch or as a floor
track winch. The winch has two brake systems:
primary and secondary. Essential winch
maintenance checks are required every week
and include inspection of the lead screw and
end nut, end of travel hard limits, gearbox chain,
all control cables, and the haulage cable.
A full stage width travelator is also used
to whisk furniture and performers on and off
stage quickly and safely. This rubber conveyor
belt is friction driven from a drum at the stageleft end of the belt. The servo-motor is bolted
directly to the gearbox and linked by chain to
the drive drum. The belt has a centre guide fin
that slots into a gap on the passive drums as
well as in the supporting floor.
A large scenic banner is revealed during the
concert scene, and made up of three segments,
one over the stalls, and two are revealed, one
each side of the auditorium. All the mechanics,
drives and motors for these were supplied and
installed by Howard Eaton Lighting. Control is
provided by Stage Technologies in the form
of ‘dry contacts’ which remotely switch the
HEL control gear. The power supply is also
incorporated into the overall e-stop system
providing additional safety.
The rose window, the abbey backing, the
crucifix and large stage masking flats are all
flown using power assisted counterweight
sets, using BT 200 winches fixed to the
counterweight frame with steel wire ropes
attached to the top and bottom of each
counterweight cradle. These winches were
also supplied by Stage Technologies and
installed by Stage Services.
The automation control was programmed
by Alex Hitchcock, who has automated
many large West End productions with
Stage Technologies including Oliver!, The
Witches of Eastwick and Mary Poppins. The
Acrobat console is the interface and translator
between the operator and the Programmable
Transmission System (PTS).
Waltz scene
“Lonely goatherd”
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Sightline Summer 2007
This system has twelve pushbuttons which
provide two key features which help ensure
safety, dual channel redundancy, which
ensures that a single fault does not lead to
loss of safety function, and cyclic monitoring,
which provides detection of the first fault by
monitoring correct operation of the safety
component at each cycle. The e-stop system
complies with BS EN 418: Safety of machinery
– emergency stop equipment.
The full installation takes an hour to check
out every day plus hours of maintenance
every week.
Geoffrey Joyce
Information kindly supplied by Stage
Technologies.
Stuart Porter, Associate
Lighting Designer
The Acrobat allows the operator to move
the winches as required to meet the desired
effect during the performance. The Acrobat
can move one or more motors at different
speeds/times and show the operator the
details the movement of each axis. The
operator knows what each scenic element or
attached performer is doing.
The operator can stop one or all motors
immediately if required.
The Maxis provides control for up to 24
separate axes. It is designed to form a central
part of the Acrobat control system. The Maxis
rack contains an electrical interface and a
sophisticated computer control system to
provide positioning and synchronisation
functions for each axis. The control system
allows individual or groups of motors to be run
accurately to a position, at a pre-determined
speed. The rack also provides synchronisation
between motors allowing more than one motor
to move a piece of scenery as required.
Critical to all of this is the fully digital IRT
1300 series drive which controls the supply
to the motor thus giving smooth operation of
motor allowing minute adjustment in speed.
Rotation is transmitted through the winch
gearboxes to drive the drums of the winches
by the HD115 and HR142 series motors. An
internal feedback device returns positional
data; in this installation all devices are
resolvers. The motors are also fitted with failsafe magnetic brakes.
The emergency stop system when activated
will bring all axes to a rapid and controlled
stop.
Typical lighting specification see plan on pages 20/21
Moving lights
19 x VL1000 AS
34 x MAC 700 Wash
39 x Martin TW1
16 x Martin MAC 700 Profile
Generic rig
44 x Source 4 10
98 x Source 4 profile
12 x PAR 64
60 x Source 4 PAR 750W
12 x 2 CRT M16 Batten 75 watt
26 x 3 CRT M16 Batten 75 watt
20 x various birdie fittings
Scrollers (all fitted with heat shields)
76 x Rainbow Pro scrollers
Smoke machines
2 x smoke machines
2 x haze machines
DMX controllable fans
Dimmers and control
1 x Hog IPC (8 Streams DMX)
1 x 8 universe City Theatrical DMX
Sound of Music
Producer: Really Useful Theatre
Company
Production manager: Matt Towell
Venue: London Palladium
Lighting designer: Mark Henderson
Associate lighting designer: Stuart
Porter
Production LX: Fraser Hall
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