ITEE Innovation Expo 2008 : Project Details

Design & Construction of a Wireless Sensor Network

The UQ School of Engineering (SoE) conducts its research activities through the accurate measurement of system variables in a static/dynamic test environment – where wired data collection is restrictive. A Wireless Sensor Network (WSN) is a network of many spatially distributed autonomous devices integrated with the capabilities of sensing, data processing and wireless communication that collectively perform an application-oriented global task. In 2008, the SoE has commenced a research initiative to design and build a WSN suitable for data collection in undergraduate research projects. The project will be undertaken in phases across several years where the WSN is continuously expanded and improved. The scope of Design Phase 1 (DP1) is as follows: 1. Design and construct two sensor nodes 2. Measure three environmental parameters: acceleration, pressure and temperature. 3. Present the environmental parameters in real time whilst providing data logging capabilities. The WSN was implemented using the IEEE 802.15.4 Zigbee protocol using readily available commercial hardware. A 12-bit hardware ADC with a maximum conversion throughput of 200kSPS was used to perform the analog-to-digital conversions. Results are stored separately for each node as comma separated values (CSV) file. All components in the node are put into sleep mode when not in use; saving battery life and improving the overall product life. DP1 has successfully proven the project concept and will be used as a stepping stone for many more future adaptations where the WSN is continuously updated and made more efficient with new features such as an energy harvesting power source.