This expresses a need for a disposable sensor module with wireless networking capabilities. Each swarm module contains one or more ultrasonic transceivers, with the capability of intelligently sending and receiving acoustic signals. An intelligent localization and characterization algorithm running on the modules will take as input the ultrasonic sensor data, location information (e.g. from GPS, or by examining RF and/or acoustic signal characteristics), and possibly other information as well, in order to gauge the size and shape of an enclosed area. A robust ad hoc networking system will communicate the information to other modules, to the warfighter, and/or to a central command station. The goal is to implement the system described using modules that are small, reliable and resilient, require minimal power, and are so inexpensive as to be expendable. Accomplishing these goals requires synergy among several areas of active research, including sensor technology, wireless ad hoc networking, RF localization, and area mapping.

In one possible situation, a handful of the modules could literally be thrown into the windows of a building. The modules would immediately and without intervention become an ad hoc wireless network. Each module would determine its own position either by using GPS or by approximation using received RF signal strength, RF signal time of arrival, and signal characteristics gathered from the onboard ultrasonic sensors. Each module would coordinate sending and receiving acoustic signals using the signal characteristics from the ultrasonic sensors to determine room size, locations or doors and/or windows, etc. By collaborating with nodes in neighboring rooms of the building, an idea of the entire building layout would be formulated and sent back to the warfighter to be displayed on a handheld device. This concept is illustrated below.