 |
|
 |
|
The Science of the CymaScope
Introduction
The CymaScope is a
new type of scientific instrument that makes sound visible. Its development
began in 2002, with a prototype that featured a thin, circular, P.V.C.
membrane; later we used latex. Fine particulate matter was used as the
revealing media. However, it was soon discovered that far greater detail
could be obtained by imprinting sonic vibrations on the surface of ultra
pure water. The surface tension of water has high flexibility and fast
response to imposed vibrations, even with transients as short-lived as a few
milliseconds. Therefore, water is able to translate many of the sinusoidal
periodicities--in a given sound sample--into physical sinusoidal structures
on the water's surface. Current limits to imprinting sound on water occur in
the higher harmonics and are due mainly to there being insufficient energy
available in this area of the audio spectrum to cause excursions of the
surface tension membrane.
In some cases the sinusoidal structures created on the surface tension are
visible beneath the water’s surface, providing partial 3D geometrical data.
These surface and sub-surface structures can readily be made visible to the
naked eye by the application of a light source arranged above the water’s
surface, either off-axis or--when using a light ring illuminator--on-axis.
Capturing the imprints, known as CymaGlyphs, is achieved by means of a
conventional digital camera or camcorder arranged vertically downward toward
the water and coaxial with it. |
|
John Stuart Reid and Erik Larson,
co-inventors of the CymaScope |
|
|
|
The generic term for the
patterns of vibration that occur on the surface of an object when excited by
an incident sound is ‘modal phenomena,’ a field of study that covers
everything from vibrations in suspension bridges, to vibrations in body
parts of cars, to the effects of sound on the human skeleton and internal
organs. In the 1970’s this branch of science was named ‘cymatics’ by Swiss
doctor Hans Jenny, a word that derives from the Greek ‘kyma,’ meaning ‘wave’
and the inspiration for the name of our CymaScope instrument. The classical
view of modal phenomena is that modal patterns form as a consequence of the
natural resonant frequencies, or modes, of the object or membrane; current
mathematical techniques used to describe this class of phenomena say nothing
about the quality of the exciting sound. Musical sounds contain many
harmonics so when a circular membrane is excited by a complex musical sound
the resulting modal pattern(s) are, naturally, also complex. If we sample a
moment from music and analyze it in terms of its fundamental frequency and
associated harmonics, and then apply that sample to, say, a circular latex
membrane of known elasticity, known diameter and fixed edge, present
mathematical
techniques cannot predict what pattern will form on the membrane. It appears
that no one has attempted to solve this problem, either because no
applications for a solution have become evident or because physicists have
not seen the importance of mathematically modeling such phenomena. Only the
pattern associated with the fundamental frequency can be predicted with any
degree of certainty. Thus, for example, the design of musical instruments
remains an art rather than a science.
Mathematical modelling of the modes of vibration of a circular flexible
membrane currently contain only such factors as shape and elacticity of the
materials; the mathematics either describe a fixed boundary condition, in
the case of a drum, or a single central fixing and a free edge in the case
of a circular Chladni plate. Bessel functions and the wave equation are
employed to define a finite number of normal modes, based on the natural
resonances of the membrane or plate.
However, the parameters for the CymaScope are quite different to the case of
the drum and the circular resonant plate. Water is free to move at the
circular boundary and across its entire surface area. In addition, water
responds not only to its normal modes but to any audible frequency imposed
on it. In other words, within the limits mentioned above, all the primary
periodicities in a given audible sound or in a given sample of music are
rendered visible. The resulting patterns can be considered as analogs of the
sound or music since the geometry in the resulting patterns is a function of
the periodicities within the exciting sound.
Applications
The CymaScope has applications in almost every branch of science simply
because vibration underpins all matter. The ability to see such vibrations
permits a depth of study previously unavailable to scientists, engineers and
researchers. Readers will have seen our list of research topics covering
subject areas from Astrophysics to Zoology. Just as great advances in
medical science have come about as the result of the microscope, and huge
strides have been made in understanding the Universe with the telescope, the
CymaScope instrument holds enormous potential to reveal the hidden realm of
sound and vibration. Our team have recently made a wonderful breakthrough in
the field of dolphin language research, to be announced soon in our
Oceanography section. However, as with all scientific instruments it is
vital that the relevant maths is developed, enabling predictions to be made
and dynamic
systems to be modelled.
If you are a student or professor of applied mathematics we invite you to
contact us to discuss a possible collabortive study of the CymaScope
instrument. Alternatively, if you are interested in acquiring a CymaScope
please drop a line to:
John Stuart Reid, Sonic Age America,
john@sonic-age.com
We hope you enjoy our photographic history of the CymaScope from its early
beginnings in 2002 to present day:
|
