A system for facilitating the mapping of a partially or fully occluded (hidden) pipeline containing a gas, a liquid, or a liquid-gas mixture. The system includes a sensor device having an internal sphere with a generally smooth outer surface and an internal orientation stabilizer. Within the internal sphere are contained a tri-axial inertial sensor, a time keeping device, a data processing device, a data recording device, and a power source. The internal sphere is centered and held within an external sphere having an inside diameter that is incrementally larger than the outside diameter of the internal sphere. The external sphere has a generally smooth unobstructed inner surface and fully encloses the internal sphere. A quantity of fluid fills the spatial gap between the outside surface of the inside sphere and the inside surface of the external sphere in a manner that permits omni-directional free rotational movement of the internal sphere within the external sphere. The use of the sensor involves the process of downloading data that has been stored within the data recording device of the internal sphere after it has traveled its path through the pipeline to be mapped.
Garth W. Tormoen