Wireless Low Power Data Acquisition Device : Embedded design and application

Sammanfattning: Embedded systems are utilized in various modern-day applications in order to ease routine tasks that are otherwise demanding in manpower; an example of which is data sensing and acquisition. Modern sensor applications usually involve one or more embedded microcomputer systems with inputs from various sensors and a means of connection to transmit the acquitted data to its point of interest. While many sensor and acquisition applications and standards exist for industrial use, the consumer/small business markets for such devices seem to be fairly bleak in comparison. In this project, various data communication standards for transmitting information between sensors and acquisition devices are investigated. Wired, such as RS232, I²C, SPI and 1-Wire, as well as wireless protocols like Wi-Fi and ZigBee were studied. Then, a generic wireless data acquisition platform is designed and realized. The reference implementation connects to a wireless LAN network over Wi-Fi, starts a web server and serves HTML5 web pages and a CSS3 style sheet from SPI flash memory. The sensor data is collected from integrated sensor circuits over an I²C link. Device can run on 3 AA batteries for a combined uptime of at least 3 weeks. Lastly, possible expansion options for the implemented device are discussed and supplemented with real-world examples where possible. Feasible consumer applications for such a platform are then given to conclude.