Visual Simple Transformations

Abstract

Empowering end-users to wire Internet of Things (IoT) objects (things and services) together would allow them to more easily conceive and realize interesting IoT solutions. A challenge lies in devising a simple end-user development approach to support the specification of transformations, which can bridge the mismatch in the data being exchanged among IoT objects. To tackle this challenge, we present Visual Simple Transformations (ViSiT) as an approach that allows end-users to use a jigsaw puzzle metaphor for specifying transformations that are automatically converted into underlying executable workflows. ViSiT is explained by presenting meta-models and an architecture for implementing a system of connected IoT objects. A tool is provided for supporting end-users in visually developing and testing transformations. Another tool is also provided for allowing software developers to modify, if they wish, a transformation's underlying implementation. This work was evaluated from a technical perspective by developing transformations and measuring ViSiT's efficiency and scalability and by constructing an example application to show ViSiT's practicality. A study was conducted to evaluate this work from an end-user perspective, and its results showed positive indications of perceived usability, learnability, and the ability to conceive real-life scenarios for ViSiT.