Node Localization in Robotic Sensor Networks for Pipeline Inspection

Robotic sensor networks provide an effective approach for underground pipeline inspection. Such networks are comprised of sensor nodes (SNs) and relay nodes (RNs) carried by robots for information sensing and communication, and are able to perform accurate and realtime inspection, especially in adverse environments. SN localization is critical in such networks because localization results can be used not only for locating and pinpointing leaks, but also for maneuvering mobile SNs in a pipeline of complex configuration. However, both the underground operational environment and the limited resources of the SNs pose significant challenges for SN localization. This paper presents algorithms for SN localization in robotic sensor networks for underground pipeline inspection. Specifically, self-localization of underground in-pipe SNs were investigated by taking into account SN movement dynamics, and using the measurements of the SN's velocity and the received signal strength (RSS) of the radio signal from aboveground RNs. Depending on the availability of the RSS at the SN, different localization algorithms based on the Kalman filter are proposed for different scenarios. Simulation results show the efficacy of the proposed algorithms. The framework also provides insight into the design of robotic sensor networks for the inspection and maintenance of other types of pipeline systems, such as oil and gas pipelines.