Applications and experiments with eBlocks - electronic blocks for basic sensor-based systems

Building a sensor-based system typically requires some programming and electronics expertise. However, some applications require only basic logic transformations and/or state maintenance of sensor information. This paper describes a set of electronic blocks, called eBlocks, that enable non-experts to build basic small-scale sensor-based systems. Each block performs a particular sensing, logic/state, or output function. A user builds a system by connecting blocks together. Each block contains a hidden microprocessor executing a pre-determined low-power compute and communication protocol. A difference between eBlocks and widely known sensor-network nodes is that each eBlock has a specific easy-to-understand function, and thus does not require programming. Further, eBlocks are designed to be connected in particular configurations to create an end application, while traditional nodes form a wireless network that must be programmed to form an application. Our physical prototypes can last for several years or more on a 9-volt battery, or can receive power from wall outlets. We describe the domain of applications for which eBlocks are suitable, including being used to build complete systems or to interface with existing sensor-network compute nodes, and we summarize the eBlock compute/communication protocol. We describe experiments, involving hundreds of users of varying levels of expertise, that demonstrate how systems that otherwise would have taken weeks or more to build can be built by non-experts in just a few minutes using eBlocks.