SAUNA QB - Array: The realization of a new concept in radioxenon detection.

We introduce a new concept in radioxenon detection - the radioxenon Array, defined as a system where air sampling and activity measurement is performed at multiple locations, using measurement units that are less sensitive, but on the other hand less costly, and easier to install and operate, compared to current state-of-the-art radioxenon systems. The inter-unit distance in the Array is typically hundreds of kilometres. Using synthetic nuclear explosions together with a parametrized measurement system model, we argue that, when such measurement units are combined into an Array, the aggregated verification performance (detection, location, and characterization) can be high. The concept has been realized by developing a measurement unit named SAUNA QB, and the world's first radioxenon Array is now operating in Sweden. The operational principles and performance of the SAUNA QB and the Array is described, and examples of first measured data are presented, indicating a measurement performance according to expectations.

Model-free execution monitoring in behavior-based robotics.

In the near future, autonomous mobile robots are expected to help humans by performing service tasks in many different areas, including personal assistance, transportation, cleaning, mining, or agriculture. In order to manage these tasks in a changing and partially unpredictable environment without the aid of humans, the robot must have the ability to plan its actions and to execute them robustly and safely. The robot must also have the ability to detect when the execution does not proceed as planned and to correctly identify the causes of the failure. An execution monitoring system allows the robot to detect and classify these failures. Most current approaches to execution monitoring in robotics are based on the idea of predicting the outcomes of the robot's actions by using some sort of predictive model and comparing the predicted outcomes with the observed ones. In contrary, this paper explores the use of model-free approaches to execution monitoring, that is, approaches that do not use predictive models. In this paper, we show that pattern recognition techniques can be applied to realize model-free execution monitoring by classifying observed behavioral patterns into normal or faulty execution. We investigate the use of several such techniques and verify their utility in a number of experiments involving the navigation of a mobile robot in indoor environments.

Evaluating gaze-driven power wheelchair with navigation support for persons with disabilities.

This article describes a novel add-on for powered wheelchairs that is composed of a gaze-driven control system and a navigation support system. The add-on was tested by three users. All of the users were individuals with severe disabilities and no possibility of moving independently. The system is an add-on to a standard power wheelchair and can be customized for different levels of support according to the cognitive level, motor control, perceptual skills, and specific needs of the user. The primary aim of this study was to test the functionality and safety of the system in the user's home environment. The secondary aim was to evaluate whether access to a gaze-driven powered wheelchair with navigation support is perceived as meaningful in terms of independence and participation. The results show that the system has the potential to provide safe, independent indoor mobility and that the users perceive doing so as fun, meaningful, and a way to reduce dependency on others. Independent mobility has numerous benefits in addition to psychological and emotional well-being. By observing users' actions, caregivers and healthcare professionals can assess the individual's capabilities, which was not previously possible. Rehabilitation can be better adapted to the individual's specific needs, and driving a wheelchair independently can be a valuable, motivating training tool.