Method and system for providing an interrupt-driven technique for monitoring one or more properties of an asset using a plurality of mobile sensor nodes in a wireless sensor network

The invention provides a method and system for monitoring one or more properties of an asset using a plurality of mobile sensor nodes. The method includes enabling a first mobile sensor node of the plurality of mobile sensor nodes to perform a data collection operation pertaining to the one or more properties of the asset. The energy status of the first mobile sensor node performing the data collection operation is then monitored. Thereafter, the first mobile sensor node performs a handover of the data collection operation to a second mobile sensor node based on the energy status of the first mobile sensor node. Finally, the data pertaining to the one or more properties of the asset is collected from the plurality of mobile sensor nodes.

FIELD OF THE INVENTION

The invention generally relates to the field of monitoring one or more properties of an asset and performing a data collection operation pertaining to the one or more properties of the asset using a plurality of mobile sensor nodes in a wireless sensor network. More specifically, the invention relates to a method and system for optimizing management of the data collection operation of the plurality of mobile sensor nodes performing the data collection operation.

BACKGROUND OF THE INVENTION

Water pipelines are generally subjected to anomalies such as leakage, bursts and corrosion that can have severe consequences for the environment and the economy. Therefore, in order to ensure the reliability of water pipelines, they must be monitored effectively. Wireless Sensor Networks (WSNs) have emerged as an effective technology for monitoring critical infrastructure such as water, oil and gas pipelines. These WSNs typically employ different type of sensors, such as temperature sensor, pressure sensor, acoustic sensor, flow sensor, and pH sensor for water pipeline monitoring. These sensors generate appropriate electrical signals based on the sensed phenomena. Generally, monitored parameters include temperature, humidity, flow and pressure. Therefore, selecting an appropriate sensor or sensing technique depends on many aspects such as the pipeline material and environment.

In the prior art, the WSNs generally employ a single mobile WSN node that performs the entire monitoring operation of a pipeline. A typical WSN node consists of a sensing subsystem, a processing subsystem, a communication subsystem and a power supply subsystem. The processing subsystem mainly includes a microcontroller and memory processes for storing the sensor data. The WSN node is allowed to move with the water current from the pipeline source down to the pipeline sink where the node is collected and its memory content is copied to a computer. The RF transceiver of the WSN node, which is an important part of communication subsystem receives commands from a central computer and transmits data collected by the static components of the WSN node to the central computer. Moreover, the power for the mobile WSN node is derived from a battery or an energy harvesting (scavenging) device.

Within the pipeline, the mobile WSN node locates measures and logs many events pertaining to the monitoring operation during its long trip within the pipeline. Consequently, the mobile WSN node must be equipped with a large memory size for accommodating the collected information and a long battery life to keep the mobile WSN node alive during its trip through the pipeline.

Moreover, the mobile WSN node must be highly reliable guaranteeing completion of the monitoring operation throughout the entire pipeline distance. In order to achieve this, the mobile WSN node is deployed with a huge physical size at a high cost. The huge size of the mobile WSN node causes the node to get trapped inside the pipeline, thus, blocking the fluid current.

Therefore, in light of the above, there is a need for an improved method and system for monitoring a long-distance pipeline using a plurality of mobile sensor nodes in WSNs.

DETAILED DESCRIPTION OF THE INVENTION

Before describing in detail embodiments that are in accordance with the invention, it should be observed that the embodiments reside primarily in combinations of method steps and system components related to monitoring of one or more properties of an asset such as a long-distance pipeline using a plurality of mobile sensor nodes.

Various embodiments of the invention provide a method and system for monitoring one or more properties of an asset such as a long-distance pipeline using a plurality of mobile sensor nodes. The method includes enabling a first mobile sensor node of the plurality of mobile sensor nodes to perform a data collection operation pertaining to the one or more properties of the asset, wherein a mobile sensor node performing the data collection operation is in an active mode and remaining mobile sensor nodes of the plurality of mobile sensor nodes are in an inactive mode. The energy status of the first mobile sensor node performing the data collection operation is then monitored. Thereafter, the first mobile sensor node performs a handover of the data collection operation to a second mobile sensor node based on the energy status of the first mobile sensor node. Finally, the data pertaining to the one or more properties of the asset is collected from the plurality of mobile sensor nodes.

FIG. 1illustrates a system100for monitoring one or more properties of an asset such as a long-distance pipeline102in accordance with an embodiment of the invention. The one or more properties of pipeline102can be, but not limited to, a leakage of pipeline102, a burst of pipeline102and a corrosion of pipeline102.

As illustrated, system100includes a plurality of mobile sensor nodes106a-106nthat flow freely within fluid104inside pipeline102. Plurality of mobile sensor nodes106a-106ncan be configured to sense one or more of, but not limited to, a fluid flow, a fluid pressure and a fluid temperature. Accordingly, plurality of mobile sensor nodes106a-106ncan be one or more of, but not limited to, a temperature sensor node, a pressure sensor node, an acoustic sensor nodes, a flow sensor node and a pH sensor node.

Plurality of mobile sensor nodes106a-106nare allowed to move with the current of fluid104and while doing so, perform a data collection operation pertaining to the one or more properties of pipeline102. A mobile sensor node performing the data collection operation is said to be in an “active mode” while a mobile sensor node that has not initiated the data collection operation is said to be in an “inactive mode” or “sleeping mode. An “active mode” refers to a state when a mobile sensor node is powered-on whereas an “inactive mode” refers to a state when a mobile sensor node is in a completely powered-down state. Generally, only a single mobile sensor node is active at a point in time.

Plurality of mobile sensor nodes106a-106nare communicatively coupled to each other through one of a wireless communication network and a wired communication network. The wireless communication network can be, but not limited to, a Wi-Fi communication network, Wireless Local Area Network (WLAN), Wireless Wide Area Network (WWAN), Wireless Metropolitan Area Network (WMAN), Wide Area Network (WAN) and telecommunication network.

Each mobile sensor node of plurality of mobile sensor nodes106a-106nperforms a data collection operation and then initiates a handover of the data collection operation to another mobile sensor node based on an energy status of the mobile sensor node. The energy status can be associated with one or more of, but not limited to, a battery status indicating the remaining battery capacity of the mobile sensor node and a memory size of the mobile sensor node.

Further, each mobile sensor node of plurality of mobile sensor nodes106a-106nis equipped with various components for enabling the mobile sensor node to perform the data collection operation and to initiate handover of the data collection operation to another mobile sensor node based on the energy status of the mobile sensor node. The various components are further described in detail in conjunction withFIG. 2.

Additionally, system100also includes a plurality of location tracking units108a-108ndeployed across outer surface of pipeline102. Plurality of location tracking components108a-108n, can be, but not limited to, radio frequency identifier (RFID) tags. Plurality of location tracking units108a-108ntrack the location of each mobile sensor node of plurality of mobile sensor nodes106a-106nin pipeline102and communicate the location information to the mobile sensor node.

After performing handover of the data collection operation, each mobile sensor node shuts down all the components and goes into a “cut-off mode”. A “cut-off mode” refers to a state when a mobile sensor node, after completing the data collection operation, is completely powered-off and does not wake up until it reaches pipeline sink110.

On reaching pipeline sink110, plurality of mobile sensor nodes106a-106ndump the collected data in a data collector112. Plurality of mobile sensor nodes106a-106ncommunicate with data collector112through a wireless communication network means114. Wireless communication network means114, can be, but not limited to, a Wi-Fi antenna for receiving the data collected from plurality of mobile sensor nodes106a-106n. The data collected by data collector112, is then, subjected to an offline analysis to identify the one or more properties associated with pipeline102.

FIG. 2illustrates various components present within mobile sensor node106afor enabling mobile sensor node106ato perform the data collection operation pertaining to the one or more properties of pipeline102in accordance with an embodiment of the invention.

As illustrated, mobile sensor node106aincludes a memory202, an energy status monitor204and a processor206.

Energy status monitor204is configured to continuously monitor an energy status of mobile sensor node106awhile mobile sensor node106ais performing the data collection operation. The energy status corresponds to one or more of, but not limited to, a battery status and an available memory size of mobile sensor node106a.

In accordance with an embodiment of the invention, mobile sensor node106ais currently in an active mode while remaining mobile sensor nodes106b-106nof plurality of mobile sensor nodes106a-106nare in an inactive mode.

While mobile sensor node106ais performing the data collection operation in the active mode, energy status monitor204that is continuously monitoring the energy status of mobile sensor node106acommunicates the energy status to processor206. Processor206, then, performs handover of the data collection operation from mobile sensor node106ato another mobile sensor node106bbased on the energy status of mobile sensor node106bas follows.

Processor206checks the energy status of mobile sensor node106acommunicated to processor206against an energy threshold. The energy threshold can be, but not limited to, a minimum value of energy required for mobile sensor node106ato perform the data collection operation. The energy threshold may be predefined for each mobile sensor node of plurality of mobile sensor nodes106a-106nbased on one or more of, but not limited to, a battery status and an available memory size for the mobile sensor node.

When the energy status of mobile sensor node106ais less than the energy threshold, processor206allows mobile sensor node106ato handover the data collection operation to mobile sensor node106bby issuing an interrupt to mobile sensor node106b.

Processor206, then, stores the data collected in memory202of mobile sensor node106awith one or more of a time stamp and a location stamp in memory202based on the location information received from plurality location tracking units108a-108n.

After performing handover of the data collection operation, mobile sensor node106ashuts down all the components and goes into the cut-off mode until it reaches pipeline sink110. At pipeline sink110, mobile sensor node106adumps the data in data collector112using wireless communication network means114.

On the other hand, on receiving the interrupt from mobile sensor node106a, mobile sensor node106bwakes up from the inactive mode and starts performing the data collection operation till the energy status of mobile sensor node106bis less than an energy threshold defined for mobile sensor node106b. When the energy status of mobile sensor node106bis less than the energy threshold defined for mobile sensor node106b, mobile sensor node106bperforms handover of the data collection operation to another mobile sensor node106cby issuing an interrupt to mobile sensor node106c. On receiving the interrupt from mobile sensor node106b, mobile sensor node106cwakes up from the inactive mode and starts performing the data collection operation till the energy status of mobile sensor node106cis less than an energy threshold defined for mobile sensor node106c.

Thus, each mobile sensor node of plurality of mobile sensor nodes106a-106nawakens only on receiving an interrupt from an active mobile sensor node and performs the data collection operation based on the energy status of the mobile sensor node.

FIG. 3illustrates a flowchart of a method for monitoring the one or more properties of pipeline102using plurality of mobile sensor nodes106a-106nin accordance with an embodiment of the invention.

As step302, mobile sensor node106aof plurality of mobile sensor nodes106a-106nis enabled to perform the data collection operation pertaining to the one or more properties of pipeline102. Thus, mobile sensor node106ais defined to be in an active mode and remaining mobile sensor node of plurality of mobile sensor nodes106a-106nare in an inactive mode.

Moving on, at step304, an energy status of mobile sensor node106aperforming the data collection operation is monitored.

Thereafter, at step306, mobile sensor node106aperforms handover of the data collection operation to another mobile sensor node106bbased on the energy status of mobile sensor node106aas follows.

Processor206checks the energy status of mobile sensor node106acommunicated to processor206against an energy threshold.

When the energy status of mobile sensor node106ais less than the energy threshold, processor206allows mobile sensor node106ato handover the data collection operation to mobile sensor node106bby issuing an interrupt to mobile sensor node106b.

On the other hand, on receiving the interrupt from mobile sensor node106a, mobile sensor node106bwakes up from the inactive mode and starts performing the data collection operation till the energy status of mobile sensor node106bis less than an energy threshold defined for mobile sensor node106b. When the energy status of mobile sensor node106bis less than the energy threshold defined for mobile sensor node106b, mobile sensor node106bperforms handover of the data collection operation to another mobile sensor node106cby issuing an interrupt to mobile sensor node106c. On receiving the interrupt from mobile sensor node106b, mobile sensor node106cwakes up from the inactive mode and starts performing the data collection operation till the energy status of mobile sensor node106cis less than an energy threshold defined for mobile sensor node106c.

Thus, each mobile sensor node of plurality of mobile sensor nodes106a-106nawakens only on receiving an interrupt from an active mobile sensor node and performs the data collection operation based on the energy status of the mobile sensor node.

Once the data pertaining to the one or more properties of pipeline102is collected by plurality of mobile sensor nodes106a-106n, at step308, the collected data is dumped in data collector112when plurality of mobile sensor nodes106a-106nreach pipeline sink110.

The method and system are further described in detail in accordance with an exemplary embodiment of the invention.

FIG. 4illustrates performing handover of the data collection operation based on the energy status of plurality of mobile sensor nodes106a-106n.

As illustrated inFIG. 4, each mobile sensor node of plurality of mobile sensor nodes106a-106nis defined with an energy status and a pre-defined energy threshold. For example, mobile sensor node106ahas an energy status Ea and a pre-defined energy threshold E1, mobile sensor node106bhas an energy status Eb and a pre-defined energy threshold E2, mobile sensor node106chas an energy status Ec and a pre-defined energy threshold E3, mobile sensor node106nhas an energy status En and a pre-defined energy threshold E4and so on. The energy threshold for a mobile sensor node is determined based on a battery status and an available memory size of the mobile sensor node.

Consider that mobile sensor node106ais already in an active mode performing the data collection operation while remaining mobile sensor nodes106b-106nof plurality of mobile sensor nodes106a-106nare in an inactive mode.

In the active mode, mobile sensor node106a, continuously measures and logs readings pertaining to the one or more properties of pipeline102. When energy status Ea of mobile sensor node106abecomes less than predefined energy threshold E1of mobile sensor node106a, mobile sensor node106astops performing the data collection operation. Mobile sensor node106a, then, issues an interrupt I1to mobile sensor node106bwhich was awaiting a trigger to start performing the data collection operation. Thereafter, mobile sensor node106ashuts down all the components and goes into a cut-off mode.

Meanwhile, on receiving interrupt I1from mobile sensor node106a, mobile sensor node106bwakes up and starts performing the data collection operation. Mobile sensor node106bperforms the data collection operation until energy status Eb of mobile sensor node106bis less than predefined energy threshold E2of mobile sensor node106b. Mobile sensor node106b, then, issues an interrupt12to mobile sensor node106c. Mobile sensor node106b, then, goes into the cut-off mode while mobile sensor node106cwakes up and starts performing the data collection operation.

Once each mobile sensor node of plurality of mobile sensor nodes106a-106nhas completed the data collection operation, the mobile sensor node completely shuts down all components going into the cut-off mode and will never wake up again until plurality of mobile sensor nodes106a-106nreach pipeline sink110.

Finally, at pipeline sink110, data collector112collects the data pertaining to the one or more properties of pipeline102from plurality of mobile sensor nodes106a-106nusing wireless communication means114.

Various advantages provided by the invention are outlined below.

The invention helps in reducing a memory size of each mobile sensor node as each mobile sensor node is configured to perform the data collection operation only for a certain distance or time within the pipeline based on the energy status of the mobile sensor node and not for the entire length of the pipeline. Hence, each mobile sensor node can have a smaller battery and memory size that significantly reduces the overall physical size of the mobile sensor node, thus, reducing the risk of the mobile sensor node getting trapped inside the pipeline.

Also, the invention reduces risk due to faulty mobile sensor nodes as the invention deploys multiple mobile sensor nodes for the monitoring and data collection operations. Thus, a faulty mobile sensor node performs handover of the data collection operation by triggering or issuing an interrupt to another mobile sensor node within the pipeline. On receiving the interrupt, the other mobile sensor node starts performing the data collection operation for the pipeline based on the energy status. Thus, the triggered active nodes perform the data collection for the rest of the pipeline. Therefore, the invention enhances coverage for monitoring as well as system reliability.

Those skilled in the art will realize that the above recognized advantages and other advantages described herein are merely exemplary and are not meant to be a complete rendering of all of the advantages of the various embodiments of the invention.