kinetic sculpture

Cyma

(2017) Data driven kinetic sculpture.
Wood, Raspberry Pi, screen, Arduino, motor & custom software.

“Cyma” (from Greek: κῦμα, meaning “wave”) is a real time data driven kinetic sculpture highly inspired by natural repeatability and wave movement. An array of wood planks, connected only with a nylon thread passed from the center, is hanged from the ceiling and reaches the floor. The bottom plank is rotating periodically and sets the whole sculpture in motion. The motion of the bottom plank is creating a wave that physically spreads from one wood to the other. Real time data of the solar wind are defining the motion of the wave. The whole sculpture is waving without any mechanical force (except from the bottom plank), in the natural fundamental frequency and in higher modes called harmonics in a hypnotic and mesmerizing way.

The movement of the sculpture is driven in real time by live data of the solar wind. The strength of the wave movement (amplitude of the modulation) is controlled by the solar wind speed and the mode of waves (fundamental or harmonics) is controlled by north-south direction of the interplanetary magnetic field (Bz). A screen placed near the sculpture, projects the data and movement visualization.

About the Data

The Deep Space Climate Observatory (DSCOVR) mission is now the primary source for real-time solar wind and interplanetary magnetic field data but there is one more satellite at the Sun-Earth L1 point that measures the incoming solar wind and and that is the Advanced Composition Explorer. This satellite used to be the primary real-time space weather data source up until July 2016 when DSCOVR become fully operational.

Animation of the satellite at the Sun-Earth L1 Lagrange point collecting the solar wind data.

The Solar Wind

The solar wind is a stream of charged particles (a plasma) released from the Sun. This stream constantly varies in speed, density and temperature. The most dramatic difference in these three parameters occur when the solar wind escapes from a coronal hole or as a coronal mass ejection. When these solar wind structures arrive at Earth they encounter Earth’s magnetic field where solar wind particles are able to enter our atmosphere around our planet’s magnetic north and south pole. The solar wind particles collide there with the atoms that make up our atmosphere like nitrogen and oxygen atoms which in turn gives them energy which they slowly release as light. The speed of the solar wind is an important factor. Particles with a higher speed hit Earth’s magnetosphere harder and have a higher chance of causing disturbed geomagnetic conditions as they compress the magnetosphere. (https://www.spaceweatherlive.com/en/help/the-solar-wind)

Illustration of the solar wind. The white lines represent the solar wind; the purple line is the bow shock produced by the interaction of the solar wind with the Earth’s protective magnetosphere (blue lines). Image not to scale. (Illustration: NASA/SOHO)

The Interplanetary Magnetic Field (IMF)

The interplanetary magnetic field (IMF) plays a huge rule in how the solar wind interacts with Earth’s magnetosphere. In this article we will learn what the interplanetary magnetic field is and how it affects auroral activity here on Earth.

The Sun’s magnetic field

During solar minimum, the magnetic field of the Sun looks similar to Earth’s magnetic field. It looks a bit like an ordinary bar magnet with closed lines close to the equator and open field lines near the poles. Scientist call those areas a dipole. The dipole field of the Sun is about as strong as a magnet on a refrigerator (around 50 gauss). The magnetic field of the Earth is about 100 times weaker.

Around solar maximum, when the sun reaches her maximum activity, many sunspots are visible on the visible solar disk. These sunspots are filled with magnetism and large magnetic field lines which run material along them. These field lines are often hundreds of times stronger than the surrounding dipole. This causes the magnetic field around the Sun to be a very complex magnetic field with many disturbed field lines.

The magnetic field of our Sun doesn’t stay around the Sun itself. The solar wind carries it through the Solar System until it reaches the heliopause. The heliopause is the place where the solar wind comes to a stop and where it collides with the interstellar medium. Because the Sun turns around her axis (once in about 25 days) the interplanetary magnetic field has a spiral shape which is called the Parker Spiral.

Bt value

The Bt value of the interplanetary magnetic field indicates the total strength of the interplanetary magnetic field. The higher this value, the better it is for enhanced geomagnetic conditions. Moderate Interplanetary Magnetic Field strength values start at 15nT but for middle latitude locations, values of 25nT or more are desirable.

(https://www.spaceweatherlive.com/en/help/the-interplanetary-magnetic-field-imf)

The Aurora

Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind that the trajectories of charged particles in both solar wind and magnetospheric plasma, mainly in the form of electrons and protons, precipitate them into the upper atmosphere, where their energy is lost. The resulting ionization and excitation of atmospheric constituents emits light of varying color and complexity (https://en.wikipedia.org/wiki/Aurora).

The Aurora above Bear Lake — Eielson Air Force Base, Alaska (18 January 2005).

Pentavlos

Kinetic installation. Acrylic tubes, balls, LEDs, motors and custom software.

Pentavlos is a kinetic light and sound sculpture, where harmony and periodicity are the fundamental elements. Motion, sound and light, all are obeying the laws of the harmonic oscillation.

Five white balls are oscillating inside acrylic tubes using the thrust of small propellers at the bottom of each system. Both balls and the tubes are emitting a light pulse and sound tone in significant point of the movement. Each tube is “tuned” in a different note of a natural pentatonic scale. The periods of the oscillations are accurately adjusted to form visual traveling waves, standing waves and quasi chaos.
There are three chapters:

•   City Memories   •   City Machines   •   City Lights

Eco-Leaf

Pentavlos is using a simple mechanism to detect the presence of visitors around it. When there are no visitors, the installation enters a standby mode where it consumes minimum energy.

 

Festivals & Exhibitions:

“Invisible Cities” exhibition, Athens, Greece (October 23, 2015)

Photos of Pentavlos

  pentavlos 1

Pentavlos and Invisible Cities

Pentavlos was presented at Italian Cultural Institution at Athens during a two day even organized by Athens University dedicated to Italo Calvino and his work “Invisible Cities”.

The periodicity and the harmonic motion, which are the key elements of the installation Pentavlos, can also be found in the novel “Invisible Cities” by Calvino. The book is divided into 9 parts, with each part containing a different number of cities. Both the length of the title of each section and how they move from one thematic group to another, follow the rules of the harmonic (sinusoidal) motion. Calvino has also chosen to integrate the periodicity to the repeated structure and the continuous alternation between dialogue and descriptions of cities.

Invicible Cities diagram

Calvino places the cities in different thematic groups in a reciprocating way that resembles that of the oscillation.

The Theory Behind Pentavlos

Harmonic motion, a periodic movement between two points, occur widely in nature. A simple harmonic oscillator is used to model and explain many phenomena in both classical physics and quantum mechanics from modeling phonons to describing quantum fields. Beyond that, a vast amount of motions, sounds, and systems in general are analyzable as superposition of simple harmonic motions of varying frequencies and amplitudes (Fourier analysis).

If we chose five different harmonic oscillators with gradually different periods, they will start together and quickly will fall out of sync, because of their different periods of oscillation, and soon they start to form visual traveling waves, standing waves and quasi chaos.

Graphical representation of five sinusoidal waves with increased periods as they fall “out of sync” and then they meet again in the same point to start over.

Graphical representation of five sinusoidal waves with increased periods as they fall “out of sync” and then they meet again in the same point to start over.


Concept animation of the five harmonic oscillators demonstrating the visual traveling waves, standing waves, beating and quasi chaos that they form across time.

Harmony and periodicity appears in many parts of the work with most important the harmonic oscillation of the balls. Additionally, the combining motion and the patterns that the five balls are producing along with way that the light fades in and out follows a sinusoidal form. The sound tones are simple sin waves that form a pentatonic scale, a scale that is consider as a very natural and harmonic.

The Sound of Pentavlos

In various significant points of the installation, for example when a ball passes from the middle of the motion path or when a tube is illuminated, the installation produces a tone. These tones are simple sinusoidal waves. All together they form a pentatonic scale with the following notes.

 

The 1st tube-ball system is playing an A3 and randomly the same note an octave higher and lower, hence A2 and A4. In the same manner the 2nd system is playing B2, B3, B4, the 3rd C#2, C#3,C#4, the 4th E2, E3, E4 and the 5th F#2, F#3, F#4.

A pentatonic scale consists of five overtones and is derived directly from the natural physical phenomenon of the harmonic series. To maximize this effect, Pentavlos is using the Pythagorean tuning and not the equal temperament notes. To form the scale we use the following formulas:

Pendulum 1st 2nd 3rd 4th 5th
Frequency Ratio 1 9/8 81/64 3/2 27/16
Note A B C# E F#
Frequency (Hz) Octave 2 110 123,8 139,2 165 185,6
Octave 3 220 247,5 278,4 330 371,25
Octave 4 440 495 556,8 660 742,5

Note: We are using the Pythagorean tuning and not the equal temperament notes.

The Technology of Pentavlos

The main parts of the installation are acrylic tubes, balls, leds and dc motors. Everything is controlled using an Arduino microcontroller. A custom android app installed on a phone is communicating via bluetooth with the Arduino and plays the sounds. The phone is also used to control various parameters of the installation (the power of the motors, the led luminosity e.c.t) .

Screenshot of the android app that was developed to play the sounds and control the installation.Screenshot of the android app that was developed
to play the sounds and control the installation.

Pentatono

Kinetic Installation. Optical fibres, LEDs, motors, arduino and custom software.

Pentatono is a kinetic light and sound sculpture, where harmony and periodicity are the fundamental elements. Motion, sound and light, all are obeying the laws of the harmonic oscillation.

Five acrylic balls are hanging from optical fibers and form five pendulums that are moving in the space using the thrust of small propellers. When a pendulum passes from the equilibrium position (the middle of the motion path) it emits a light pulse and sound tone. Each pendulum is “tuned” in a different note of a natural pentatonic scale. The lengths and hence the periods of the pendulums are accurately adjusted to form visual traveling waves, standing waves and quasi chaos.

Pentatono at St. Nicolas Kirk, Aberdeen, UK for SPECTRA 2017 Light Festival. Photo by Michèle Emslie.

Festivals & Exhibitions:

Maintenant 2017, Reenes, France (October 10, 2017)
SPECTRA 2017, Aberdeen, United Kingdom (February 09, 2017)
Bnl Media Art Festival, Rome, Italy (April 13, 2016)
B-Seite Festival, Mannheim , Germany (March 12, 2016)

Photos of Pentatono

 

AP-logo
Selected for 2016 Aesthetica Art Prize Longlist.
LOGOSpecial Price of Kinetica Museum London.
Google-Cultural-InstitutePresented at Google Cultural Institute Featured in Arduino.org / Makers

The Theory Behind Pentatono

Harmonic motion, a periodic movement between two points, occur widely in nature. A simple harmonic oscillator is used to model and explain many phenomena in both classical physics and quantum mechanics from modelling phonons to describing quantum fields. Beyond that, a vast amount of motions, sounds, and systems in general are analyzable as superpositions of simple harmonic motions of varying frequencies and amplitudes (Fourier analysis).

While this underlying fundamental principle – the fourier series – is a purely abstract mathematical theorem, it is also responsible for our understanding of almost every aspect of the physical, biological and social world; including but not limited to acoustics, economics, quantum mechanics, predicting earthquakes, protein structures, DNA and the composition of distant stars and galaxies.Memo Akten about “Simple Harmonic Motion Series”

The pendulum is a simple harmonic oscillator. The period of a pendulum (T) depends on its length:   where L is the length of the pendulum and g is the local acceleration of gravity. We have chosen different lengths for the pendulums in order to have different periods. After we start all 5 pendulums together, they quickly fall out of sync, because of their different periods of oscillation, and soon they start to form visual traveling waves, standing waves and quasi chaos.

The installation is using the fundamental frequency (resonant frequency) of each pendulum in order to oscillate it. If T is the period of the pendulum, the motor is activated every T seconds for ½T of time.

Graphical representation of five sinusoidal waves with increased periods as they fall “out of sync” and then they meet again in the same point to start over.

Graphical representation of five sinusoidal waves with increased periods as they fall “out of sync” and then they meet again in the same point to start over.

 
Concept animation of the five pendulums demonstrating the visual traveling waves, standing waves, beating and quasi chaos that they form across time.

Ηarmony and periodicity appears in many parts of the work like:

• The harmonic oscillation of the pendulums.
• The combining motion and the patterns that the five pendulums are producing.
• The sound tones are a simple sinusoidal tones.
• Various properties of light like maximum and minimum luminosity or fade out speed are following a sinusoidal form.
• The pentatonic scale is consider a very natural and harmonic scale. It consists of five overtones and is derived directly from the natural physical phenomenon of the harmonic series. To maximize this effect, Pentatono, is using the Pythagorean tuning and not the equal temperament notes.

The Sound of Pentatono

When a pendulum passes from the equilibrium position (the middle of the motion path) it produces a tone. These tones are simple sinusoidal waves. All together they form a pentatonic scale with the following notes.

 

The 1st pendulum is playing an A3 (and randomly the same note an octave higher and lower) A2 and A4. In the same manner the 2nd pendulum is playing B2, B3, B4, the 3rd C#2, C#3,C#4, the 4th E2, E3, E4 and the 5th F#2, F#3, F#4.

The 1st pendulum is playing an A3 (and randomly the same note an octave higher and lower) A2 and A4. In the same manner the 2nd pendulum is playing B2, B3, B4, the 3rd C#2, C#3,C#4, the 4th E2, E3, E4 and the 5th F#2, F#3, F#4.

A pentatonic scale consists of five overtones and is derived directly from the natural physical phenomenon of the harmonic series. To maximize this effect, Pentatono, is using the Pythagorean tuning and not the equal temperament notes. To form the scale we use the following formulas:

Pendulum 1st 2nd 3rd 4th 5th
Frequency Ratio 1 9/8 81/64 3/2 27/16
Note A B C# E F#
Frequency (Hz) Octave 2 110 123,8 139,2 165 185,6
Octave 3 220 247,5 278,4 330 371,25
Octave 4 440 495 556,8 660 742,5

Note: We are using the Pythagorean tuning and not the equal temperament notes.

The Technology of Pentatono

The main parts of the installation are optical fibres, leds, dc motors and acrylic spheres. Everything is controlled using an Arduino microcontroller. A custom android app installed on a phone is communicating via bluetooth with the Arduino and plays the sounds. The phone is also used to control various parameters of the installation (the power of the motors, the led luminosity e.c.t) .

Screenshot of the android app that was developed to play the sounds and control the installation.Screenshot of the android app that was developed
to play the sounds and control the installation.

Inspiration

A major inspiration to this work was the “Simple Harmonic Motion” series of projects by Memo Akten.

References: