Research

Crisis management, Resilience and Impact Evaluation

The need for improving Critical Infrastructure Protection (CIP) due to its high societal impact has led to an increase in the budget assigned by governments to research in this field; an incipient area of knowledge where several questions still need to be answered, such as: which are the interdependencies between different CIs? How does a society achieve a suitable commitment between investments in crisis preparation and the losses due to a crisis? How do we avoid repeating the same mistakes all over again?

Crises are complex phenomena, most often inevitable and whose management is complicated. To facilitate the management process, it is necessary to conduct a thorough analysis of both the resilience of the system and the possible impacts that may result from a crisis. Resilience means the ability of a system to prevent the occurrence of a crisis and the system's ability to reduce its impact. A correct analysis and evaluation of the Resilience and impacts can help crisis managers to develop preventive measures and response programs, which may help to increase the systems' resilience minimizing and even preventing future crises.

System Dynamics and Group Model Building

The development of simulation models allows gaining an overall view and a better understanding of complex systems. System dynamics is a computer-aided approach to policy analysis and design. It applies to dynamic problems arising in complex social, managerial, economic, or ecological systems -- literally any dynamic systems characterized by interdependence, mutual interaction, information feedback, and circular causality. The resulting models allow understanding the causes of undesirable dynamics and design new policies to ameliorate/eliminate them. The feedback concept is at the heart of the system dynamics approach. Diagrams of loops of information feedback and circular causality are tools for conceptualizing the structure of a complex system and for communicating model-based insights.

Simulation modelling methodologies such as System Dynamics is usually linked with collaborative modelling methodologies where modellers work on the problem jointly with multidisciplinary domain experts. Gathering information from different experts is a crucial process to guarantee that these simulation models compile and integrate the fragmented mental models of different stakeholders. So, this process requires the use of a collaborative methodology that encourages consensus building among the involved agents. Group Model Building (GMB) is an effective methodology of defragmenting partial mental models found in representative multi-disciplinary teams. GMB elicits partial mental models, identifies holes in knowledge, resolves clashes and ambiguities, achieves insight and creates consensus. The result is new explicit knowledge.

Haptic Rendering

The real-time computation of the forces and torques applied to users as a result of their actions in a Virtual Reality application is a complicated and essential task in order for haptic interfaces to be effective and applicable in many fields. We have developed a haptic rendering method that allows for realistic and stable interaction with virtual environments. The method ensures an improved haptic response by seeking a compromise between accuracy and computational cost. The research has been especially focused on complex virtual contacts, such as multiple simultaneous collisions or geometrical discontinuities.

Collision Detection and Collision Response

Haptic technology is quite recent and therefore in many cases it is difficult to simulate real contacts or interactions with a high sensation of realism. Collision response methods that calculate the force-feedback tend to cause haptic instabilities when the normal direction changes abruptly. In consequence, collision or contact events are often difficult to render properly in sharp corners by means of haptic devices. This work describes a collision response method which not only provides users with a stable force feedback, but also a comfortable and convincing haptic interaction. The experimental results show that this approach leads to a smoother force evolution which manages to avoid discontinuities and enhances the quality in the interaction with corners.

Multisensory Interaction

We have analysed the effectiveness of combining different sensory modalities available on the system to improve the perception of virtual events. On one hand, we have evaluated the influence of auditory feedback for haptic accessibility tasks in aeronautic virtual environments. On the other hand, we have investigated a combination of pseudo-haptic and sensory substitution techniques to simplify the mechanical design of a haptic wrist.