Monitoring a large construction site using wireless sensor networks

Despite the significant advances made by wireless sensor network research, deployments of such networks in real application environments are fraught with significant difficulties and challenges that include robust topology design, network diagnostics and maintenance. Based on our experience of a six-month-long wireless sensor network deployment in a large construction site, we highlight these challenges and argue the need for new tools and enhancements to current protocols to address these challenges.This research has been funded by the EPSRC Innovation and Knowledge Centre for Smart Infrastructure and Construction project (EP/K000314/1). We would like to thank Costain-Skanska Joint Venture (CSJV) and our industrial partner Crossrail for allowing access and instrumentation of the Paddington site. We would also like to thank Dr Munenori Shibata from Japan Railway Technical Research Institute for his assistance with network deployment.This is the author accepted manuscript. The final version is available from ACM via http://dx.doi.org/10.1145/2820990.2820997 Data supporting this paper is available from https://www.repository.cam.ac.uk/handle/1810/250538

Wireless sensor monitoring of Paddington Station Box Corner

This paper presents the real performance of three diaphragm wall panels on the southeast corner of Paddington Station Box during excavation, monitored using a wireless sensor network. In total, 15 LPDT displacement sensors, 12 tilt sensors, 13 relay nodes and a gateway were deployed at three different stages. Each wireless sensor node is programmed with Contiki OS using the in-built IPv6-based network layer (6LoWPAN/RPL) for link-local addressing and routing, and ContikiMAC at the medium access control (MAC) layer for radio duty cycling. Extensive testing and calibration was carried out in the laboratory to ensure that the system functioned as expected. Wireless tilt and displacement sensors were installed to measure the inclination, angular distortion and relative displacement of these corner panels at three different depths. The monitoring data reveal that the corner produced a stiffening effect on the station box, which might result in a breakdown of plane strain conditions. The network performance characteristics (e.g. message reception ratio and network topology status) and challenges are also highlighted and discussed

Monitoring on the performance of temporary props using wireless strain sensing

Although temporary props have been extensively used in underground support systems, their actual performance is poorly understood, resulting in potentially conservative and over-engineered design. This paper presents the performance monitoring of 4 temporary props in an urban construction site using a newly developed wireless strain sensor node featuring a 24-bit ADC. For each prop, 6 strain gauges and 3 temperature sensors were directly attached onto the prop surface using super glue, and then connected to a wireless strain sensor node mounted in the middle span. Each sensor node transmitted both monitoring data and network diagnostic messages in near-real-Time over an IPv6-based (6LoWPAN) wireless mesh sensor network. The data were also stored locally at each node on a micro SD card. Extensive testing and calibration was undertaken in the laboratory to ensure that the system functioned as expected. The prop loads are presented without correction for temperature effects and compared with the design loads. The monitoring data reveal the development of loads in temporary props during excavation, the formation of the basement and the extraction of the props. The network performance characteristics in terms of message reception ratio and network topology evolution are also highlighted and discussed

How to see through the Fog? Using Peer to Peer (P2P) for the Internet of Things

The Internet of Things (IoT) faces the challenge of scaling to handle tens of billions of connected devices. This challenge is made more difficult by the range of constituent IoT parts from Cloud-based applications to constrained nodes in Wireless Sensor Networks (WSNs). Achieving the desired scale and interoperability requires an architecture for IoT that is scalable and allows seamless operation across networks and devices. This paper considers the requirements for IoT and considers a number of existing architectural approaches and the emergence of Fog computing. It proposes that Fog computing architectures must cater for the flow of data from constrained sensor nodes to powerful applications. It considers the suitability of a Peer to Peer (P2P) approach for Fog computing. Using a prototype implementation, it demonstrates how a Holistic Peer to Peer (HPP) architecture and application layer protocol meet the requirements set for IoT

Using a DHT in a Peer to Peer architecture for the Internet of Things

A challenging aspect of The Internet of Things (IoT) is to provide an architecture that can handle the range of IoT elements ranging from Cloud-based applications to constrained nodes in Wireless Sensor Networks (WSNs). Such an architecture must be scalable, allow seamless operation across networks and devices with little human intervention. This paper describes a set of abstractions and an architecture for the flow of data from sensors to applications supported by a Distributed Hash Table (DHT) and our novel Holistic Peer to Peer (HPP) Application Layer protocol to handle node ids, capabilities, services and sensor data. We show that this architecture can operate in a constrained node by presenting a `C' implementation running on the Contiki3.0 OS and consider the effectiveness of its use of a DHT and its abstractions

Monitoring a large construction site using wireless sensor networks

Despite the significant advances made by wireless sensor network research, deployments of such networks in real application environments are fraught with significant difficulties and challenges that include robust topology design, network diagnostics and maintenance. Based on our experience of a six-month-long wireless sensor network deployment in a large construction site, we highlight these challenges and argue the need for new tools and enhancements to current protocols to address these challenges

Data supporting the conference paper 'Monitoring A Large Construction Site Using Wireless Sensor Networks'

This data consists of displacement and inclination sensor data from an excavation at a construction site at Paddington, London between 17/02/2015 and 17/08/2015 and transmitted using a wireless sensor network. Accompanying this data is a location of each of the sensors within the construction site. A portion of this data has been used to generate the figures presented in the paper "Monitoring A Large Construction Site Using Wireless Sensor Networks".This work was supported by the EPSRC [grant number EP/K000314/1]