ISPRS 2016
Tangible Landscape
Cognitively grasping the flow of water
Brendan Harmon, Anna Petrasova, Vaclav Petras, Helena Mitasova, & Ross Meentemeyer
Tangible Landscape
A tangible user interface powered by open source GIS
Tanigble interaction with GIS
With Tangible Landscape you can hold a GIS in your hands - feeling the shape of the earth, sculpting its topography, and directing the flow of water.
History
An evolution of Illuminating Clay and the Tangible Geospatial Modeling System
Image source: MIT Media Lab
How-it-works
Tangible Landscape couples a digital and a physical model through a continuous cycle of 3D scanning, geospatial modeling, and projection
Features
A collaborative environment for tangible freeform modeling, object detection, real-time geospatial analytics, 3D rendering, and immersion / VR
Intuitive scientific modeling with Tangible Landscape
Tangible Landscape is designed to enable a rapid iterative process of observation, hypothesizing, testing, and inference
Research aim
How do 3D tangible interfaces for GIS mediate spatial thinking about landscape processes like water flow?
Research questions
- Can users offload the cognitive work of understanding and shaping topographic form onto the body?
- Can users dynamically explore how topographic form influences landscape processes?
Experiment
Participants were asked to sculpt a given landscape in 10 minutes using a) a digital modeling program and then b) Tangible Landscape's water flow analytic
Their perfomance was assessed using cellular statistics and hydrological simulation
Vue
Terrain editor
3D modeling program designed for intuitive terrain sculpting
Tangible Landscape
Water flow analytic
Water flow simulation
A path sampling technique for solving the shallow water flow continuity equation
Implemented in GRASS GIS as the module r.sim.water
Elevation
a) The reference landscape, b) the mean of digitally sculpted models, c) and the mean of tangibly sculpted models
Water flow
Water depth on a) the reference landscape, b) the mean of digitally sculpted models, c) and the mean of tangibly sculpted models
Difference in water flow
The difference between the reference water depth and a) itself, b) the mean water depth of digitally sculpted models, c) and the mean water depth of tangibly sculpted models
Depressions
The depth of depressions in a) the reference landscape, b) the mean of digitally sculpted models, c) and the mean of tangibly sculpted models
Percent cells with depressions
| Exercise | Cells |
|---|---|
| Reference | 0% |
| Digital | 44% |
| Tangible | 17.66% |
Findings
Digital modeling
Participants focused on making streams lower than their surroundings, rather than directing continuous flows
- Diffuse water flow
- Extensive pooling in depressions
Findings
Tangible modeling
While most participants did not clearly understand how topography directs water flow at first, they began to learn about curvature and continuity with the aid of the tangible interface
- More accurately replicated the flow of water over the study landscape
- More flow in stream channels
- Less pooling in depressions
- The spatial distribution of water flow more closely fit the reference
Observations
We observed participants using an iterative modeling process with the tangible interface:
- Sculpting
- Studying the updated water flow simulation
- Critiquing the form of their model
- Continuing to sculpt
Conclusions
Seeing the water flow simulation update in near real-time enabled participants to generate hypotheses, test hypotheses, and draw inferences about the way that water flows over topography.
As one participant said, `seeing the flow takes away the mystery of topography.'
Open source | Open science
Fork us on GitHub
Tangible Landscape plugin for GRASS GIS
GRASS GIS module for importing data from Kinect v2
Repository with experiment instructions, scripts, data, and results
Future work
Learn more
Read our book or visit our website at http://tangible-landscape.github.io/ and give it a try