Soil processes are difficult to observe because i) long-lived, dependable sensors do not exist for many important modalities, and ii) below-ground soil characteristics (unobserved) introduce significant latent spatial variability in sensor data that can be difficult or impossible to adequately resolve. Thus, collecting every data point and ensuring it is usable is important because there is less data to be collected even in the best case.

We are working to design a wireless sensing system designed for soil environments. This system consists of i) a new sensorboard designed to handle ion-selective electrodes, used to monitor contaminants in groundwater and soil, ii) a javelin pylon, an enclosure designed to facilitate the deployment and replacement of sensors, and iii) in-situ calibration techniques to minimize labor-intensive and disruptive sensor calibration events that require removing the sensor from the soil. Conference paper, EPA White Paper, and data are available.

Being embedded in the physical world, sensor networks present a wide range of bugs and misbehavior qualitatively different from those in most distributed systems. Unfortunately, due to resource constraints, programmers must investigate these bugs with only limited visibility into the application. We designed Sympathy, a tool for detecting and debugging failures in sensor networks. Sympathy has selected metrics that enable efficient failure detection, and includes an algorithm that root-causes failures and localizes their sources in order to reduce overall failure notifications and point the user to a small number of probable causes. Sympathy is used in most of our mote-based deployments. Documentation, and code (Sink / Node) are available.

Various projects have been based on Sympathy. One group at IIT Kanpur ported Sympathy to their Bridge Monitoring application. Another group used the Sympathy infrastructure to detect routing attacks. Sympathy is also used as the basis for DAS.

Conference and Journal papers, class lecture, and poster are also available.