Wireless Sensor Networks Configurations for Applications in Construction

Prototyping is considered at both the hardware and software level. Although the techniques and constraints differ in hardware and software configuration, the objectives and methodologies can be quite similar. In order for rapid prototyping to be successful, the development process has to be well-defined as well as the prototype architecture or design. In This research modular hardware is utilized to facilitate the rapid prototyping and faster redesign. This approach enables the reuse of the same hardware modules in several framework configurations, which are used for different applications. The modular platform used in this research consists of three-layer as shown in Figure 1. This modular platform consists of three layers according to their function: processing, radio frequency communication, and sensing. The processing layer consists of a micro-controller, which is responsible for data pre-processing. The radio frequency communication layer consists of one or more communication modules, which are responsible for the network interconnection and data transmission. The sensing layer consists of a number of sensors, which are selected according to the targeted application.

Figure 1: WSN Modular Platform

Prototype Design Objectives

When designing wireless sensor networks for applications in construction management, two major classes of design objectives must be considered; network architecture and application requirements.

Network Topology and Architecture

The wireless sensor network architecture has several implication on network features, such as data routing algorithms, sensor nodes communication range and network lifetime. The physical network topology identifies the network organization as well as the sensor nodes density....

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...s accelerometer is used for measuring the accelerations in the three dimensions. The Xbee communication module is used to connect and send the collected data through the wireless network. This communication module has a coverage range of 150 m and 250 kbit/s data transfer rate.

Figure 3: Infrastructure Monitoring Prototype

Table 1 summarizes the measured energy consumption of the platform we presented in this research. The energy consumption is measure in mj/day for each task. The measurement is based on data collection every 4 seconds, which is averaged and transmitted to the parent node once every 5 minutes. Each branch has a parent node and a maximum of 5 children nodes. The energy consumption is calculated by summing the energy usage of each executed task: Data communication, Node discovery, Alarm Monitoring, Sensor Data Sampling, and sleep mode energy.