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LINEAR MOTION
Museum’s 4D ride
has added muscle
Visitors to Manchester Museum of
Science and Industry can now
experience a “four-dimensional”
immersive ride, during which their seats
are moved by a novel form of pneumatic
linear actuator. The 4D Theatre’s seats
subject their occupants to a variety of
movements, synchronised to the film
being shown, along with special effects
including water sprays and air blasts.
The ride has been developed by
Simworx, a specialist developer of 4D
effects theatres and simulation attractions,
based in Kingswinford, West Midlands.
The company is a world leader in
designing and manufacturing stationary
and mobile 4D effects theatres and
simulation attractions, with more than 600
installations worldwide at sites including
aeronautical and science museums in the
UK and US, and theme parks in Europe.
The seats for Simworx' latest
Dimensions theatres are based on a
modular design, with all of the motion
actuators incorporated in a shallow, floorstanding
plinth that supports four seats.
The most sophisticated models offer
forwards/backwards and left/right tilting
movements, as well as vertical drops. The
headrest of each seat can be fitted with
optional water sprays and air blasts, and
the pedestal can be fitted with a
pneumatically-powered leg tickler.
Over the years, Simworx has used
various actuators from different suppliers
to achieve its dynamic effects. Most have
been pneumatic, because this is a safe,
cost-effective technology which offers a
higher power density than electric
actuators, making it easier to integrate
into the body of the seat.
While developing its latest seats,
Simworx became aware of Festo's “fluidic
muscle” technology – a unique form of
tensile pneumatic actuator which mimics
biological muscles by contracting when
fed with compressed air. These actuators
are capable of fast, smooth operation, as
well as slow, jolt-free movements, and can
generate an initial force about ten times
higher than a conventional pneumatic
actuator of a similar diameter.
According to Simworx director, Andy
Roberts, when he first saw fluidic muscles
being demonstrated, “it was immediately
apparent that the muscles are considerably
better than conventional pneumatic
actuators for simulator-type applications
like ours. They provide excellent dynamic
performance, and have a much higher
power density.”
Simworx is using the most powerful,
40mm-diameter versions of Festo's latest
DMSP series fluidic muscles for its new
seats. The muscles use press-fit
connections to minimise size and weight.
Each four-seat plinth module contains four
fluidic muscles – one in each corner –
together with four manifold-mounted
Festo VPPM proportional pressure
regulators, and a controller. The cascaded
dual-stage regulators provide an easy,
precise means of varying flow rates to the
actuators. To minimise noise interference,
the compressed air supply is generated
outside the theatre and is distributed to
each seat module via a “pneumatic ring
main”. The exhausted air is released
locally, via silencers.
The controller in each seat module
communicates with a host control PC via a
fieldbus system. Special event triggers in
the film being shown instruct the central
controller to issue appropriate signals to all
of the seat modules in the theatre
simultaneously, resulting in the entire
audience experiencing exactly the same
effect – be it pitch, rock, vibrate or a
The theatre’s seats incorporate
powerful “fluidic muscles”
in a shallow floor-standing plinth
sudden drop – at the same time.
Following the Manchester museum
installation, Simworx is supplying a
Dimensions system for an indoor theme
park on Weston-super-Mare's newly
rebuilt Grand Pier. “I envisage we'll be
making increasing use of this technology
in the future,” says Roberts. D&C
www.drives.co.uk November/December 2010 23