Prototype the Structure
Several custom built hardwares and advanced computing techniques had been used to build the interface of this project. The physical structure consists of two basic modules which are, FTIR interface and Cymascope. Each module has almost the same body and when combined together, they create the entire installment. Additionally an Arduino microcontroller located inside of the FTIR module that controls most of the events happening inside the prototype.
The top surface of the FTIR module consists of 35 by 25 centimeter piece of 10mm thick acrylic glass. Also, the frame that holds the glass in place is covered with a custom made array of Infrared LED’s. These special LED’s emits only infrared light which is not visible to the human eye. A similar system could be built with normal LED’s however, it would cause serious problems such as, being affected by natural or ambient light, as I experienced in my previous prototypes.
To be able to put different materials on the glass, and provide a tactile input to the spectator, a complement surface had been made by using Tinkerman method. Complement surface consists of a waterproof silicon, which was applied to a plastic film by using a soft foam roller. Yet, this process creates a texture very similar to human skin and responsive to the FTIR surface.
The materials that create a texture on the FTIR surface are, mat (represents the distortion effect), bubble wrap (noise effect), soft towel (ambient echo), and table cloth made of synthetic cotton (delay effect). Pressure that spectators finger will apply on these materials, going to measured by a touch sensor located below the frame and going to set the effect level. As the spectator touches on the materials, relative effects will be triggered and applied on the ambient sound.
FTIR surface video can be found on this link: https://www.youtube.com/watch?v=D26N-rHWL_s
An Arduino microcontroller used to operate components of the prototype such as, LED’s and pressure sensor. Basically, it has three tasks to do. First of all, controlling the IR LED’s condition, whether they are switched on or off, to decrease power consumption. Since IR LED’s are 1.5 volts, an octocoupler used to separate two circuits that are working with different voltages. Secondly, controls the color of RGB LED’s to create unique color mixture on the liquid holder. Finally, gets data from pressure sensor which is placed under the acrylic frame.
Cymascope module of the installment consists of a black acrylic liquid holder, a speaker, sound transmitter tube, membrane and RGB LED’s. The final solution to transfer sound waves from the speaker to liquid is created by the influence of tonoscope. One end of the tube glued to the speaker and the other end enclosed by a flexible membrane. Thus, any interaction between the air inside and outside of the tube had been blocked. As a result, the motion created by up and down movement of the speaker can directly be transferred to the liquid holder. Ultimately, according to the vibration frequency different patterns can emerge on the liquid surface. Liquid holder has chosen to be black, in order to reduce reflections coming from other sources rather than LED’s. The reason why the RGB light sources located on the sides of the liquid holder is to make colorful patterns visible from all sides.
Cymascope video can be found on this link: https://www.youtube.com/watch?v=fs0oehisD8U