An essential component in the ubiquitous computing vision is the ability of detecting with which objects the user is interacting during his or her activities. We explore in this paper a solution to this problem based on wireless motion and orientation sensors (accelerometer and compass) worn by the user and attached to objects. We evaluate the performance in realistic conditions, characterized by limited hardware resources, measurement noise due to motion artifacts and unreliable wireless communication. We describe the complete solution, from the theoretical design, going through simulation and tuning, to the full implementation and testing on wireless sensor nodes. The implementation on sensor nodes is lightweight, with low communication bandwidth and processing needs. Compared to existing work, our approach achieves better performance (higher detection accuracy and faster response times), while being much more computationally efficient. The potential of the concept is further illustrated by means of an interactive multi-user game. We also provide a thorough discussion of the advantages, limitations and trade-offs of the proposed solution.

A coordinated team of mobile wireless sensor and actuator nodes can bring numerous benefits for various applications in the field of cooperative surveillance, mapping unknown areas, disaster management, automated highway and space exploration. This article explores the idea of mobile nodes using vehicles on wheels, augmented with wireless, sensing, and control capabilities. One of the vehicles acts as aleader, being remotely driven by the user, the others represent thefollowers. Each vehicle has a low-power wireless sensor node attached, featuring a 3D accelerometer and a magnetic compass. Speed and orientation are computed in real time using inertial navigation techniques. The leader periodically transmits these measures to the followers, which implement a lightweight fuzzy logic controller for imitating the leader's movement pattern. We report in detail on all development phases, covering design, simulation, controller tuning, inertial sensor evaluation, calibration, scheduling, fixed-point computation, debugging, benchmarking, field experiments, and lessons learned.

Autonomous vehicles are used in areas hazardous to humans, with significantly greater utility than the equivalent, manned vehicles. This paper explores the idea of a coordinated team of autonomous vehicles, with applications in cooperative surveillance, mapping unknown areas, disaster management or space exploration. Each vehicle is augmented with a wireless sensor node with movement sensing capabilities. One of the vehicles is the leader and is manually controlled by a remote controller. The rest of the vehicles are autonomous followers controlled by wireless actuator nodes. Speed and orientation are computed by the sensor nodes in real time using inertial navigation techniques. The leader periodically transmits these measures to the followers, which implement a lightweight fuzzy logic controller for imitating the leader's movement pattern. The solution is not restricted to vehicles on wheels, but supports any moving entities capable of determining their velocity and heading, thus opening promising perspectives for machine-to-machine and human-to-machine spontaneous interactions in the field. Visit [1] to see a video demonstration of the system.