Abstract
In this paper we report on a methodology to model pedestrian behaviours whilst aggregate variables are concerned, with potential applications to different situations, such as evacuating a building in emergency events. The approach consists of using UWB (ultra-wide band) based data collection to characterise behaviour in specific scenarios. From a number of experiments carried out, we detail the single-file scenario to demonstrate the ability of this approach to represent macroscopic characteristics of the pedestrian flow. Results are discussed and we can conclude that UWB-based data collection shows great potential and suitability for human trajectory extraction, when compared to other traditional approaches.

Abstract
The development of intelligent wheelchairs is a very good solution to assist severely handicapped people who are unable to operate classical electrical wheelchair by themselves in their daily activities. This paper describes the integration of a robotic simulator with our intelligent wheelchair shared control and planning modules. An adapted version of the free Cyber-Mouse robotic simulator was used to simulate the movement of the intelligent wheelchair in a hospital environment. Adaptations of the subsumption architecture, Strips Planning and A* Algorithms were employed and integrated to allow wheelchair intelligent behavior. The experimental results have demonstrated the success of the integration of these algorithms in our simulator allowing very safe motion of the intelligent wheelchair in the simulated hospital environment. Also, the adapted Cyber-Mouse simulator proved its capability and robustness in simulating the hospital environment and wheelchair physic characteristics.

Abstract
The area of object/people location consists on the identification of their instantaneous movement in a given area of space and during a given time frame. This location takes an important role because it can help rectify trajectories (in the case of autonomous objects) or improve the performance (in the case of sport practices). In this research project, a system based on RFID that automatically rectifies a location and calculates a wheelchair trajectory in a pre-defined route will be presented. For that, a commercial location system was used as well as a wheelchair and two routes: a linear one and a complex route. In order to correct the trajectory a low pass filter was also used. The obtained results showed that this approach decreased 38% of the mean squared error and in more than 7 centimeters the maximum error. In the future this research work will be enclosed in a new project where a multi agent system capable of executing a management of an autonomous wheelchair set in a hospital environment will be developed. © 2011 AISTI.

Abstract

Abstract
Many people with disabilities find it difficult or even impossible to use traditional powered wheelchairs independently by manually controlling the devices. Intelligent wheelchairs are a very good solution to assist severely handicapped people who are unable to operate classical electrical wheelchair by themselves in their daily activities. This paper describes a development platform for intelligent wheelchairs called IntellWheels. The intelligent system developed may be added to commercial powered wheelchairs with minimal modifications in a very straightforward manner. The paper describes the concept and design of the platform and also the intelligent wheelchair prototype developed to validate the approach. Preliminary results concerning automatic movement of the IntellWheels prototype are also presented.

Abstract
Intelligent wheelchairs operating in dynamic environments need to sense its neighborhood and adapt the control signal, in real-time, to avoid collisions and protect the user. In this paper we propose a robust, real-time obstacle avoidance extension of the classic potential field methodology. Our algorithm is specially adapted to share the wheelchair's control with the user avoiding risky situations. This method relies on the idea of virtual forces, generated by the user command (attractive force) and by the objects detected on each ultrasonic sensor (repulsive forces), acting on the wheelchair. The resultant wheelchair's behavior is obtained by the sum of the attractive force and all the repulsive forces at a given position. Experimental results from drive tests in a cluttered office environment provided statistical evidence that the proposed algorithm is effective to reduce the number of collisions and still improve the user's safety perception. ©2010 IEEE.