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A Mobility-Aware Adaptive Duty Cycling Mechanism for Tracking Objects during Tunnel Excavation

View Article: PubMed Central - PubMed

ABSTRACT

Tunnel construction workers face many dangers while working under dark conditions, with difficult access and egress, and many potential hazards. To enhance safety at tunnel construction sites, low latency tracking of mobile objects (e.g., heavy-duty equipment) and construction workers is critical for managing the dangerous construction environment. Wireless Sensor Networks (WSNs) are the basis for a widely used technology for monitoring the environment because of their energy-efficiency and scalability. However, their use involves an inherent point-to-point delay caused by duty cycling mechanisms that can result in a significant rise in the delivery latency for tracking mobile objects. To overcome this issue, we proposed a mobility-aware adaptive duty cycling mechanism for the WSNs based on object mobility. For the evaluation, we tested this mechanism for mobile object tracking at a tunnel excavation site. The evaluation results showed that the proposed mechanism could track mobile objects with low latency while they were moving, and could reduce energy consumption by increasing sleep time while the objects were immobile.

No MeSH data available.


Mobility support in MA-MAC (redrawn from [21]).
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sensors-17-00435-f003: Mobility support in MA-MAC (redrawn from [21]).

Mentions: Light-weight Mobility-Aware MAC (MA-MAC) [21] for wireless sensor networks was also proposed. MA-MAC extends X-MAC (a contention based scheme) and provides short preambles. MA-MAC detects mobility by using the RSSI of ACK packets and attempts to seamlessly handover communication to achieve better performance. A node can be found in one of five states: Sleep, Receive, Send, Discover, and Handover. In the initial step, a node stays in Sleep state. The node wakes up at any time if it has data to send and enters the Send state. To receive data, the node periodically wakes up and changes its state to Receive. If the node detects a discovery request, it enters a Discovery state and searches for an intermediate neighbor before breaking the link. If the node receives a discovery reply, it enters Handover state. If the handover attempt is successful, the node shifts to Send state, or otherwise, goes back to sleep. A handover process is shown in Figure 3. When a sender recognizes the mobility of Receiver 1 by estimating the RSSI of incoming ACK, the sender broadcasts data with a discovery request. Receiver 2 and Receiver 3 wake up to participate in discovering a new intermediate node that takes over Receiver 1. If Sender 1 receives a discovery reply from Receiver 2 or Receiver 3, Sender 1 updates its routing configuration and sends the data for R1 to the intermediate node.


A Mobility-Aware Adaptive Duty Cycling Mechanism for Tracking Objects during Tunnel Excavation
Mobility support in MA-MAC (redrawn from [21]).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5375721&req=5

sensors-17-00435-f003: Mobility support in MA-MAC (redrawn from [21]).
Mentions: Light-weight Mobility-Aware MAC (MA-MAC) [21] for wireless sensor networks was also proposed. MA-MAC extends X-MAC (a contention based scheme) and provides short preambles. MA-MAC detects mobility by using the RSSI of ACK packets and attempts to seamlessly handover communication to achieve better performance. A node can be found in one of five states: Sleep, Receive, Send, Discover, and Handover. In the initial step, a node stays in Sleep state. The node wakes up at any time if it has data to send and enters the Send state. To receive data, the node periodically wakes up and changes its state to Receive. If the node detects a discovery request, it enters a Discovery state and searches for an intermediate neighbor before breaking the link. If the node receives a discovery reply, it enters Handover state. If the handover attempt is successful, the node shifts to Send state, or otherwise, goes back to sleep. A handover process is shown in Figure 3. When a sender recognizes the mobility of Receiver 1 by estimating the RSSI of incoming ACK, the sender broadcasts data with a discovery request. Receiver 2 and Receiver 3 wake up to participate in discovering a new intermediate node that takes over Receiver 1. If Sender 1 receives a discovery reply from Receiver 2 or Receiver 3, Sender 1 updates its routing configuration and sends the data for R1 to the intermediate node.

View Article: PubMed Central - PubMed

ABSTRACT

Tunnel construction workers face many dangers while working under dark conditions, with difficult access and egress, and many potential hazards. To enhance safety at tunnel construction sites, low latency tracking of mobile objects (e.g., heavy-duty equipment) and construction workers is critical for managing the dangerous construction environment. Wireless Sensor Networks (WSNs) are the basis for a widely used technology for monitoring the environment because of their energy-efficiency and scalability. However, their use involves an inherent point-to-point delay caused by duty cycling mechanisms that can result in a significant rise in the delivery latency for tracking mobile objects. To overcome this issue, we proposed a mobility-aware adaptive duty cycling mechanism for the WSNs based on object mobility. For the evaluation, we tested this mechanism for mobile object tracking at a tunnel excavation site. The evaluation results showed that the proposed mechanism could track mobile objects with low latency while they were moving, and could reduce energy consumption by increasing sleep time while the objects were immobile.

No MeSH data available.