Improving the Scalability and Replicability of Embedded Systems Remote Laboratories through a Cost-Effective Architecture

Abstract

Online remote laboratories are a particularly promising tool for effective STEM education. They offer online universal access to different hardware devices in which students can experiment and can test and improve their knowledge. However, most of them have two significant limitations. First, given that most of them are developed as, or evolve from single-user proofs of concept, they have no scalability provisions other than full laboratory replication. And second, when this is done, cost efficiency is often neglected. This paper presents the requirements for the creation of a novel remote laboratory architecture focused on, but not limited to, embedded systems experimentation. An architecture, based on Redis (an open source, in-memory data structure store, which is often used as database, cache or message broker), a modular design, and hardware-sharing techniques, is proposed in order to achieve the combined requirements of high scalability and cost efficiency. This mixed hardware-software architecture serves as a basis for the development of remote laboratories, especially those focused on microcontroller-based systems experimentation and embedded devices experimentation. From a user perspective the architecture is web-based, and has provisions to be easily adaptable to different Learning Management Systems and different hardware embedded devices. A new microcontroller-oriented remote laboratory based on the architecture has been developed, with the aim of providing valid evaluation data, and has been used in a real environment. The architecture and the resulting remote laboratory have been compared with other state of the art remote laboratories and their architectures. Results suggest that the proposed architecture does indeed meet the main requirements, which are scalability through replicability and cost efficiency. Furthermore, similarly to previous architectures, it promotes usability, universal access, modularity and reliability.