Tangible Landscape couples a digital and a physical model through
a continuous cycle of 3D scanning, geospatial modeling, and projection.
Research questions (1)
In order to use real landscapes,
we need to link our changes on the physical model to
the actual geospatial data. What are the steps and
information we need to georeference a model
and ensure we run the geospatial analyses at the right location and scale?
How the limitations of Kinect and other available scanners
in terms of the resolution, precision and noise influence the scale of the models and
applicability to certain geospatial analyses?
Are there ways to compensate for these limitations during the DEM reconstruction or
the way we design applications?
Research questions (2)
Given the available data from Kinect sensor
what types of physical interactions can we use to steer geospatial models
and how do we translate these interactions into modified inputs to the models?
What types of geospatial models
can be meaningfully linked with tangible interfaces in terms of
processing speed and input data?
How do we compromise between the realistic setting of the input parameters and
the need for real-time feedback and visually engaging results?
Since physical models cannot be scaled, what are the options
to study and interact with multiscale processes?
Tangible Landscape design
supports wide range of applications (design, decision making,
education) in various domains (geology, landscape design, ecology, ...)
enables using simple to complex geospatial models and algorithms,
and allows scientists to develop their workflows
allows for different interactions to let user input different data into models
works with landscapes with different geographic scale and extent
accessible financially and without restrictions
Physical setup
Sensor properties (resolution, FOV),
projector properties (resolution, aspect ratio, throw ratio)
and the physical setup influence the maximum size of the model and precision.
Kinect data processing 1: georeferencing
Calibration: automated correction for tilted scanner
Model extraction: manual bounding box selection, automated edge trimming procedure
Georeferencing:
rotation along Z axis and 3D rotation to correct for tilted scan,
horizontal, vertical scaling and translation based on provided DEM
Kinect data processing 2: DEM reconstruction
Point cloud filtering to remove invalid points and outliers using neighborhood statistics filter
Noise removal using Moving Least Squares surface reconstruction method
Raster-based DEM reconstruction:
binning with filling empty cells - fast, leaves no data values where Kinect can't see
interpolation using regularized spline with tension - slower
r.in.kinect
GRASS add-on module:
written in C++
using open source libraries
GRASS GIS library
Point Cloud Library (used in computer vision and robotics)
libfreenect2 library (open source drivers for Kinect)
libfreenect2pclgrabber by Giacomo Dabisias
Software
Coupling with GRASS GIS:
wide range of analyses + cartography
open source, so we can modify it
scriptable
Developed library for modeling
topographic parameters
surface processes
designing trails
Interfaces
TUIGUIAPI
Interactions
surface
points
lines
areas
Applications: topographic analysis
slope
cut and fill
erosion
landforms
Applications: solar analysis
Solar irradiation and cast shadow
Applications: hydrology (1)
Serious game: save houses from coastal flooding by building coastal defenses
Applications: hydrology (2)
Lake Raleigh dam break simulation
Applications: wildfire spread
Applications: visibility
Applications: 3D soil moisture exploration
Applications: trail planning
Optimized trail routing between waypoints based on walking time,
topography, and cost maps with feedback including trail slopes
Applications: termite infestation
Serious game: Manage the spread of termites across a city by treating city blocks
using a model of biological invasion in R
Applications: Sudden Oak Death
Manage the spread of SOD in California
Applications: urban growth
Simulation of urban growth scenarios with FUTURES model
Tangible Landscape + Immersive Virtual Reality
Publications
Tonini F., Shoemaker D., Petrasova A., Harmon B., Petras H., Cobb R. C., Mitasova H. and Meentemeyer R. K. (2016).
Using tangible geospatial modeling for collaborative problem-solving: a pilot exercise with an invasive plant pathogen.
Submitted to Ecological Modelling.
Harmon, B. A., Petrasova, A., Petras, V., Mitasova, H., Meentemeyer, R. K. (2016).
Tangible Landscape: cognitively grasping the flow of water.
In The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences.
NCSU GeoForAll laboratory, Tangible Landscape at the State of the Sciences: Museum Takeover (2016),
Nature Research Center at the North Carolina Museum of Natural Sciences.
Urban growth modeling with FUTURES and Tangible Landscape
Research questions (1)
FUTURES as a complex spatio-temporal model requires considerable
expertise and training for correct data preparation and running the model
as it was intended. How can we facilitate urban growth modeling with
FUTURES and achieve more reproducible results while at the same time
keep the model flexible and not oversimplify the modeling process?
Previous urbanization studies using original FUTURES model limited the
study extent to several counties. Can we study large scale urbanization
with FUTURES at the same level of detail as the previous studies but
still using commonly available computing infrastructure?
Goals
make FUTURES open source
describing models in journal articles does not ensure reproducible results
peer-review leads to better code and intended model behavior
model can be extended or adapted and used in different context
FUTURES
FUTure Urban-Regional Environment Simulation
stochastic, patch-based land change model
simulates urban growth
accounts for location, quantity, and pattern of change
positive feedbacks (new development attracts more development)
allows spatial non-stationarity
Integration in GRASS GIS
Why choose GRASS GIS and not keep it standalone?
all needed GIS functions at hand
efficient I/O libraries
able to process large datasets
modular architecture: modules in C/C++ and Python
automatically generated CLI and GUI
infrastructure for online manual pages and distribution of binaries
maintained by community and developers
DEMAND submodel
projects the rate of per capita land consumption for each simulated year and each subregion
curve fitting using simple linear regression and by solving non-linear least squares problem (SciPy)
can select best curve for each subregion based on residuals
Development pressure
important predictors of where development is likely to happen
computed as a distance decay function of neighboring developed cells
moving window analysis with custom designed matrix filters
precomputing the matrix of distances results in faster processing
multilevel logistic regression for development suitability surface
package lme4 for fitting generalized linear mixed-effects models and
package MuMIn for automatic model selection
Patch growing algorithm
stochastically allocates seeds for new development across the development suitability surface
use of efficient read and write libraries speeds up initialization
dynamic memory allocation to enable flexible number of predictors and computational extent
more suitable data types to reduce memory consumption
replaced a suboptimal linear search method with binary search
parallelized by (a) running stochastic runs in parallel
or (b) splitting by counties, running those in parallel and finally merge back
FUTURES version
memory
1 run
250 runs
original
1.7 GB
60 s
4 h 10 min
r.futures
0.86 GB
19 s
1 h 20 min
Asheville Metropolitan Region, laptop with 64-bit Ubuntu 14.04 LTS,
Intel Core i7-4760HQ $@$ 2.10GHz using 1 CPU and running on external hard drive
Patch calibration
calibrate the input patch compactness and size to
match the simulated patterns with the observed patterns from reference period
distributions of patch shapes and sizes is compared using chi-square distance
parallelized
Research questions (2)
How can we integrate FUTURES and similar complex spread simulations
such as SOD with tangible geospatial interface? What types of human-computer
interactions can we employ to allow intuitive exploration of the
model behavior and scenarios?
Scenario modeling
Constraint parameter: zones with decreased probability of development
$$P_{new} = P . C, \quad C \in \langle 0, 1\rangle $$
Stimulus parameter: zones with increased probability of development
$$P_{new} = P + S - P.S, \quad S \in \langle 0, 1 \rangle$$
Future work
how to deal with stochastic processes?
adaptive management
Publications
Petrasova, A., Petras, V., Van Berkel, D., Harmon, B. A., Mitasova, H., and Meentemeyer, R. K. (2016)
Open Source Approach to Urban Growth Simulation.
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLI-B7, 953-959.
Pickard, B. R., Van Berkel, D., Petrasova, A., Meentemeyer, R. K.
Future patterns of urbanization reveal trade-offs among ecosystem. Accepted to Landscape Ecology.