==== Design research for  ProjectLyta ====
{{/LytaPlan1c.jpg|LytaPlan1c.jpg}}

== Contents ==

See also the topic [[Project Lyta Materials Research]]

==== Cabinet and Frame Construction ====


=== Exterior ===

The cabinet will be a robust, sculpted form about 3 x 2 x 0.4 meters in size.  The surface will be covered with a membrane designed to enhance the tactile qualities of the interaction. Underneath this membrane, the installation will consist of a frame articulated with a system of closely spaced plates. The plates are to be coupled to an internal mechanism actuating the local inward and outward displacement. A depiction of one of the simplest possible skeletons:


{{LytaExterior1c.jpg|LytaExterior1c.jpg}}










=== Interior ===

The internal structure will consist of a set of staggered frames.  These will be designed to isolate the surface from the actuating mechanism, and to provide a mounting substrate for the actuators themselves.  The isolation frame will also serve to brace and align the mechanical translation mechanism, depicted here as a rod:




{{LytaProtoNewSmall2.jpg|LytaProtoNewSmall2.jpg}}



[[LytaProtoNewSmall2Small.mov]]


Quicktime Animated  interior sequence.






==== Electro-Mechanics ====


Some collected research on actuation and sensing is available under [[Project Lyta Materials Research]] 


=== Actuation ===

Human Touch Sensing for Actuators in Haptic Interfaces: Good overview of quantification of human tactile and kinesthetic sensing capabilities: http://www-cdr.stanford.edu/touch/actuators/Actuators_Sensing_Summary.html


After surveying many possible solutions, there are two main categories of actuation we are considering: electrical and pneumatic.  (Those we have found to be best adapted to our needs will be described in more detail here time permitting.)

In autumn 2004 we have decided for a pneumatic system from Merlin: http://www.merlinsystemscorp.com/

Illustration of system integration with muscle-type actuators:


{{MuscleActuator1A.jpg|MuscleActuator1A.jpg}}

{{MuscleActuator1B.jpg|MuscleActuator1B.jpg}}



=== Sensing ===

Among the options we are considering are:  

  * Position-dependent switches
  * Pressure sensors (force-sensing resistors)
  * Stretch sensors
  * Other position encoders

Although still looking around, most probably our chosen system will be the FSR pressure sensors from LuSense (http://www.lusense.com)

product description: http://www.b2blocator.co.uk/build/items/00/69/108.html


==== Tactile (Soft) Materials ====

Over the front panel of the installation a membrane will be stretched in order to improve the tactile qualities of the tablet. This material and design research is underway by [[Rachel Wingfield]], [[Maja Kuzmanovic]], [[Evelina Kusaite]].
The membrane might be designed in 3 layers:

  * outer layer made from a strong, transparent, elastic membrane such as the 'technoGel': http://www.technogel.it/, a shape memory polymer that, when pressed moulds itself to the shape of each individual, in 3 axis
  * chromic or light emiting materials to enchance the visual feedback of the touch - when pressed emits colour light (see ProjectLytaMaterialsResearch and ActiveMaterials for more information)
  * potentially a piezoelectric sensor-actuator composite (such as the adaptive materials from http://www.empa.ch/) - although this proves not to be feasible in the given time frame
	

==== Electronic Control and Networking ====

This will involve a set of microcontrollers and network interfaces provided by Merlin and FoAM. A computer will be embedded in the installation (potentially running custom built software as well as Max/MSP or PD.) This part of the installation will be decided on in the coming months.

==== Use Research ====


Research results from the 2002  FoAM  public Lyta prototype event in Antwerp at MUKHA:

  * the 'pin cushion' idea is playful enough even at very low resolution (10-15cm)
  * when the players know that they are interacting with a person, they tend to become more engaged, playful, but also aggressive
  * the more displacement of the pins, the more force people tended to use
  * rather than transmitting touch, this installation transmitted force
  * attention span lasted for not more than 5 minutes at the time. Larger groups 1-2 minutes.
  * better resolution is needed for transmission of shape data
  * a membrane is crucial for structural integrity
  * smooth and subtle motion could diminish violent tendencies
  * not much instruction is needed. The interaction seemed to be clear enough, with just one notice ' wash your hands and touch the walls'
  * ...