Figure 3. SandScape. Users alter the form of the landscape
model by manipulating sand while seeing the resultant effects of
computational analysis generated and projected onto the
surface of sand in real time.
ble representations of digital models of the buildings.
To change their location and orientation, users simply
grab and move the physical model, rather than a
mouse, to point to and drag a graphical representation
on a screen. The physical form of Urp’s building models and the information associated with their position
and orientation on the workbench represent and control the state of the urban simulation.
Although standard GUI interface devices (such as
keyboards, mice, and screens) are also physical, the
physical representation in a TUI provides an important distinction. The physical embodiment of the
buildings (representing the computation in building
dimensions and location) allows for the tight coupling
of control of the object and manipulation of its parameters in the underlying digital simulation.
In Urp, the building models and interactive tools
are physical representations of digital information
(shadow dimensions and wind speed) and computational functions (shadow interplay). The physical artifacts also serve as controls for the underlying
computational simulation (specifying the locations of
objects). The specific physical embodiment allows
dual use in representing the digital model and the
control of the digital representation.
However, Urp lacks the ability to change the forms
of tangible representations during user interaction.
Users must use a predefined finite set of fixed-form
objects (building models in this case) and change only
the spatial relationship among them, not the form of
individual objects. All tangible objects in Urp must be
predefined (physically and digitally) and are unable to
change their forms on the fly. This is why the Tangible Media Group designed the second generation of
“organic” TUI.
SANDSCAPE: SECOND-GENERATION TUI
The advent of new sensing and display technologies
made it possible to add dynamic form development
into TUIs, suggesting movement toward new digital/physical materials that seamlessly couple sensing
and display capabilities. Rather than using predefined
discrete objects with fixed forms, the Tangible Media
Group developed new types of organic TUIs that utilize continuous tangible material (such as clay and
sand) for rapid form sculpting for landscape design;
examples include Illuminating Clay [ 6] and SandScape [ 2]. With the advent of flexible materials that
integrate fully flexible sensors and displays, this category of organic TUI shows great potential to express
ideas in tangible form.
SandScape [ 2] is an organic tangible interface for
designing and understanding landscapes through a