abstract
Internet of Things (IoT) technologies can facilitate the preventive conservation of cultural heritage (CH) by enabling the management of data collected from electronic sensors. This work presents an IoT architecture for this purpose. Firstly, we discuss the requirements from the artwork standpoint, data acquisition, cloud processing and data visualization to the end user. The results presented in this work focuses on the most critical aspect of the architecture, which are the sensor nodes. We designed a solution based on LoRa and Sigfox technologies to produce the minimum impact in the artwork, achieving a lifespan of more than 10 years. The solution will be capable of scaling the processing and storage resources, deployed either in a public or on-premise cloud, embedding complex predictive models. This combination of technologies can cope with different types of cultural heritage environments.
Conclusions and future work
In a preventive conservation campaign of artworks, evaluating the environmental conditions in a building provides an overall perspective that allows specific actions to be implemented in spaces according to their climatic conditions, the possibilities of applying passive control actions, and to assist in designing a subsequent follow-up strategy. The present work has studied the viability of applying IoT technologies to CH by analysing the requirements and proposing the appropriate cloud and field systems for these requirements. Since the sensor node is the most critical element, different RF technologies were analysed for their viability. The standard defacto LoRa and Sigfox in the ISM of 868 MHz band were found to be suitable for monitoring artworks. The elected wireless technology copes with the need of reaching relative long distances and pass through thick walls that are typical scenarios in artwork containers or open archaeological sites. The energy requirements were then calculated based on the typical RH and temperature measurement requirements at a rate of one sample per hour. Using a small 1.7 mAh lithium-thionyl battery it is possible to achieve a node life-span of over 20 years with no maintenance for LoRa and 1.5 years for Sigfox. The Sigfox technology is useful for monitoring widely dispersed artworks and, hence, it should not be ruled out. With other strategies such as carrying more than one sample per transmission to optimize the energy transmitted, it would be easy to extend node life-span to 5 years. LoRa technology is clearly ideal for a CH scenario, but Sigfox can be considered if there is a good trade-off between node maintenance and gateway needs.
