Node/Proxy portability: Designing for the two lives of your next WSAN middleware

Middleware for wireless sensor and actuator networks (WSANs) provides powerful programming abstractions which simplify application development. While it is highly desirable to reuse WSAN middleware across a wide range of hardware platforms, in practice, complex middleware may not fit in nodes with limited resources. As one possible solution, we propose the so-called proxy approach: the middleware is ported on a general purpose computer, from where the sensors and actuators of the resource-constrained nodes are accessed remotely yet in a way that is transparent to the application, which runs unmodified, as if it resided on the physical nodes. We provide design guidelines and a middleware transformation process for implementing the proxy approach in a structured way. We also present a concrete implementation of the proxy approach for our own middleware, along with a performance evaluation of the proxy software environment in a wired testbed with almost 200 sensor nodes. © 2016 Elsevier Inc. All rights reserved

Soft Actuation: Smart Home and Office with Human-in-the-Loop

Considerable effort in the area of context-aware systems goes into applications that process sensor data to proactively drive actuators. However, there are concerns about such fully automated operation. Most notably, due to imperfect context inferences, actuating decisions can be contrary to the user's desires. In this article, the authors focus on what they refer to as soft actuation: issuing low-key, nonverbal hints prompting the user to optionally perform a simple manual operation on a nearby object. Soft actuation targets noncritical applications for the home or office. In the spirit of calm technology, special care is taken to respect the user's attention. The authors elaborate the interaction concept and present its experimental evaluation 'in the wild.' The results are encouraging, given that users liked the soft-actuating system and accepted quite a few hints. © 2015 IEEE