The Design of a Spreadsheet Programming Interface for Sensor Networks

Sensor networks are currently difficult to program and maintain. To simplify programming we present an interface for program- ming sensor networks based on the concept of spreadsheets. Our interface is explicitly designed to handle habitat monitoring and animal tracking scenarios, which we believe constitute a large portion of sensor network applications. Our approach is simple enough so that scientists without strong programming backgrounds can still program and maintain a network of sensors. This Work-in-Progress explores the design of our interface and scenarios in which our design does well. This WIP also briefly explores some challenges we faced while designing our interface. We also discuss possible extensions to our design and applications that may benefit from those extensions. I. I NTRODUCTION Sensor network technology has the potential to greatly simplify data collection in many of the natural sciences. However, sensor networks largely remain difficult to program, especially for non- Computer Scientists. Languages such as NesC, although useful for research and low level programming, poses a large programming barrier. Current approaches to simplify sensor network programming take advantage of the idea that a sensor network can be treated as an online multi-dimensional database. This virtual database is then queried using multi-dimensional range queries (1). Current implementations involve using a language similar to SQL to express such queries (2). Although these SQL variants work well for networks with a small number of dimensions that exhibit regular behavior, we argue that such languages are unsuitable for more complex sensor networks. For this Work-in-Progress, we discuss the design of a spreadsheet programming interface for sensor networks. We show that by employing a spreadsheet programming model, we can alleviate much of the complexity of designing multi-dimensional range queries while remaining flexible and powerful. II. USAGE SCENARIOS Our programming interface was explicitly designed to easily handle habitat monitoring and animal tracking scenarios. These two appli- cation types can encapsulate many different deployment scenarios while allowing flexibility in the details of the deployment. Since our interface is designed for non-Computer Scientists dealing with ecology oriented deployments, we felt that a spreadsheet interface was the most appropriate interface. Habitat monitoring scenarios often involve stationary sensors placed in the environment that regularly take readings. Oftentimes, the environment is static enough so that the sensors and basestation can be placed near each other to ensure communication. Ecology- based examples of such deployments include Great Duck Island (3) and a more recent JPL microclimate study at the Sevilleta National Wildlife Refuge in New Mexico. 1.