Hydrosys
Advanced spatial analysis tools for on-site environmental monitoring and management.
System platform
The system infrastructure and integration research and development forms the core of the HYDROSYS system platform, to allow the access to and visualisation of data from the sensor network on the cellphones and mobile computers. Next to work on the general system platforms for the display devices, and small components like a collaboration module, considerable research and development effort has been spent on the following issues.
Visualization
HYDROSYS' users can access multivariate hydrological and environmental data which is visualized on the mobile/handheld devices. In order to support the on-site analysis, visualization methods generally used by hydrologists and environmentals scientists are adapted to run in real-time on these small devices. Due to the size of the handheld displays, and the computing power of the devices, the methods have been extremely optimized. Visualization includes the handling of large map data sets, 3D models of various data sets, and simulation data visualizations. The visualization methods are applied both as overlay on map-like visualizations, and registered to the real-environment using overlay techniques (augmented reality).
In order to optimize the representations (visibility) on the small screens, content has been modulated and perceptually optimized, among others through focus+context methods that let users focus attention on specific parts of content, or to visualy adapt the appearance of environmental data representations, for example through transparency or the usage of contour lines. These techniques allow the user to compare different kinds of visualizations from the multivariate sensors.
Results
At the handheld computers, users are able to browse through sensor data and simulations that can be displayed as point data labels registered in the environment (augmented reality labels) and various optimized simulation overlay, embedded in video content. The cellphones allow browsing of similar data connected to a 3D model of the environment in a list or plot-based fashion. Multiple studies have been performed on modulation of representations, to draw the attention of the user on particular aspects in the environment, so called saliency techniques, of which several implementations exist. Furthermore, in cohesion with user interface studies, a comprehensive investigation of perceptual issues for representation and interpretation of augmented content was performed to optimize display of content on small displays.Publications
Veas, E., Mendez, E. Feiner,S., Schmalstieg, D. Directing Attention and Influencing Memory with Visual Saliency Modulation. In Proceedings of the ACM Conference on Human Factors in Computing Systems (CHI2011)
Kruijff, E., Swan II, E., Feiner, S. Perceptual Issues in Augmented Reality Revisited. In Proceedings of the 9th IEEE and ACM International Symposium on Mixed and Augmented Reality (ISMAR'10), Seoul, Korea, 2010.
Mendez, E., Feiner, S., Schmalstieg, D. Focus and Context in Mixed Reality by Modulating First Order Salient Features. In Proceedings of the ACM International Symposium on Smart Graphics, 2010. [PDF]
Mendez, E., Schmalstieg, D., Feiner, S. Experiences on Attention Direction through Manipulation of Salient Features. In Proceedings of the IEEE Virtual Reality Workshop on Perceptual Illusions in Virtual Environments (IEEE VR 2010), 2010 [PDF]
Hybrid tracking
HYDROSYS end-users often work in difficult terrains. Tracking users in such terrains requires hybrid localization techniques combining which are complementing each other. This task focuses on the integration of different sensors consisting of GPS, inertial sensors, ultra wide band signalling and computer-vision based techniques to obtain robust results. A global estimation scheme will use both relative measurements between devices and vehicles and absolute measurements through GPS to optimize the individual position estimates. In order to integrate different sensors, their statistics must be known to a high degree of accuracy. Currently, the existing sensors (ultra wide-band, GPS, inertial and magnetic) have been fused. New sensors including a computer vision system to localize position using the visible horizon.
Results
Within the vehicle setup, a major milestone has been successfully reached in terms of building and setup the system. The setup test has been conducted in Davos on March 2010 with University of Cambridge. The service transmitting the 3D real time localisation data has been implemented and successfully tested. On the other hand, in order to predict the system performance and behavior and also to setup and test the hybrid tracking together with the University of Cambride, Ubisense has been working on the simulation using a real world reference including the system setup. This enables investigating the potential limitations of the system by assessing most of all possible situations and therefore to adapt the hybrid tracking algorithm.
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A part of the hybrid tracking platform consists of a ultra-wide band tracking system. This solution consists in equipping a car with a set of sensors connected to a Power Over Ethernet (PoE) switch onboard the truck and track people (equipped with small localization tags) moving in the area around the vehicle. This solution has the advantage of being movable and easy as the sensors are mounted on the vehicle with a fixed configuration.
Handheld user interface showing simulation overlays and multi-camera system.
Handheld user interface showing multi-camera system.
Cellphone user interface showing data overlay.
Cellphone user interface showing reconstructed environment.








