Sensor enclosures: example application and implications for data coherence

Sensors deployed in natural environments, such as rivers, beaches and glaciers, experience large forces and damaging environmental conditions. Sensors need to be robust, securely operate for extended time periods and be readily relocated and serviced. The sensors must be housed in materials that mimic natural conditions of size, density, shape and roughness. We have developed an encasement system for sensors required to measure large forces experienced by mobile river sediment grains. Sensors are housed within two discrete cases that are rigidly conjoined. The inner case exactly fits the sensor, radio components and power source. This case can be mounted within outer cases of any larger size and can be precisely moulded to match the shapes of natural sediment. Total grain mass can be controlled by packing the outer case with dense material. Case design uses Solid-WorksTM software, and shape-matching involved 3D laser scanning of natural pebbles. The cases were printed using a HP DesignjetTM 3D printer that generates high precision parts that lock rigidly in place. The casings are watertight and robust. Laboratory testing produces accurate results over a wider range of accelerations than previously reported

Bioans: bio-inspired ambient intelligence protocol for wireless sensor networks

This paper describes the BioANS (Bio-inspired Autonomic Networked Services) protocol that uses a novel utility-based service selection mechanism to drive autonomicity in sensor networks. Due to the increase in complexity of sensor network applications, self-configuration abilities, in terms of service discovery and automatic negotiation, have become core requirements. Further, as such systems are highly dynamic due to mobility and/or unreliability; runtime self-optimisation and self-healing is required. However the mechanism to implement this must be lightweight due to the sensor nodes being low in resources, and scalable as some applications can require thousands of nodes. BioANS incorporates some characteristics of natural emergent systems and these contribute to its overall stability whilst it remains simple and efficient. We show that not only does the BioANS protocol implement autonomicity in allowing a dynamic network of sensors to continue to function under demanding circumstances, but that the overheads incurred are reasonable. Moreover, state-flapping between requester and provider, message loss and randomness are not only tolerated but utilised to advantage in the new protocol

Study of Challenges in Sensor Node Deployment in Wireless Sensor Network

Wireless Sensor Network is a network which consists of tiny sensors that senses required information from the sorrounding and passes it to the destination for further processing. Deployment of sensor node in wireless sensor network is the way of placing sensors in network for the collection of desired information from environment. Performance of a network in an application depends on the proper deployment of the sensor nodes. Particularly, when it is the case of heterogeneous sensor network, at most focus is required while deploying sensor nodes. Improper deployment reduces the efficiency of the network. It may not be always possible to deploy the sensor nodes easily .Particularly, in harsh environment, it is too difficult to deploy the nodes. In this paper we give a description of the different types of node deployment schemes and challenges developed so far for wireless sensor network

Energy efficient multi-target tracking in heterogeneous wireless sensor networks

Title from PDF of title page, viewed on June 3, 2011VitaIncludes bibliographical references (p. 30-32)Thesis (M.S)--School of Computing and Engineering. University of Missouri--Kansas City, 2011Tracking multiple targets in an energy efficient way is an important challenge in wireless sensor networks (WSNs). While most of the prior work consider tracking multiple targets as execution of single target tracking algorithms multiple times and utilize only single parameters for efficient energy consumption, we identify multiple parameters that can influence the energy efficiency of sensors in the WSN. We observe that there are several impacting parameters that can affect the energy efficiency of the sensors in the WSN which are: the relative location of the sensor with respect to the target's motion, multiple targets tracked by the sensor, and the remaining energy in the sensor. These impacting parameters are used to decide the tracking state of the sensors and further, our observations reveal the implications of combining these parameters and we identify that the optimal energy consumption is governed by their usage in particular network conditions. Based on these observations we proceed to propose our Adaptive Multi-Target Tracking (AMTT) algorithm that can identify the local network conditions for individual sensors in distributed environment without any centralized co-ordination, and uses required combination of impacting parameters to achieve energy efficiency.Introduction -- Related work -- Proposed multi-target tracking system -- Simulation setup and results -- Conclusions and future wor

Wireless Sensor Network Deployment for Monitoring Wildlife Passages

Wireless Sensor Networks (WSNs) are being deployed in very diverse application scenarios, including rural and forest environments. In these particular contexts, specimen protection and conservation is a challenge, especially in natural reserves, dangerous locations or hot spots of these reserves (i.e., roads, railways, and other civil infrastructures). This paper proposes and studies a WSN based system for generic target (animal) tracking in the surrounding area of wildlife passages built to establish safe ways for animals to cross transportation infrastructures. In addition, it allows target identification through the use of video sensors connected to strategically deployed nodes. This deployment is designed on the basis of the IEEE 802.15.4 standard, but it increases the lifetime of the nodes through an appropriate scheduling. The system has been evaluated for the particular scenario of wildlife monitoring in passages across roads. For this purpose, different schemes have been simulated in order to find the most appropriate network operational parameters. Moreover, a novel prototype, provided with motion detector sensors, has also been developed and its design feasibility demonstrated. Original software modules providing new functionalities have been implemented and included in this prototype. Finally, main performance evaluation results of the whole system are presented and discussed in depth

PERFORMANCE & SIMULATION ANALYSIS OF SENSOR AREA COVERAGE

Wireless sensor networks (WSNs) have been employed in numerous military and civilian applications. Some application areas are in battlefield, surveillance, biological detection, and environmental monitoring. A major challenge to such applications is the sensor areacoverage (SAC), which refers to the techniques and mechanisms of placing sensors and their coordination in a mission space (field) to monitor the physical environment in such a way to achieve the application coverage objectives. This thesis develops a sensor area coverage package (SACPac) that simulates some selected coverage algorithms and their enhancements, and analyzes their performance parameters under various scenarios. The performance parameters considered include coverage ratio, resiliency of the field coverage against sensor failures, energy efficiency, and security of communication among sensors. The thesis also develops a prototype of communication for sending the position of an object via a mobile device to the server on which SACPac runs, so that the object trajectory can be displayed. SACPac provides the foundation for further enhancements and future research. It can also be used as an educational tool for those interested in the SAC problem

Design and analysis of adaptive hierarchical low-power long-range networks

A new phase of evolution of Machine-to-Machine (M2M) communication has started where vertical Internet of Things (IoT) deployments dedicated to a single application domain gradually change to multi-purpose IoT infrastructures that service different applications across multiple industries. New networking technologies are being deployed operating over sub-GHz frequency bands that enable multi-tenant connectivity over long distances and increase network capacity by enforcing low transmission rates to increase network capacity. Such networking technologies allow cloud-based platforms to be connected with large numbers of IoT devices deployed several kilometres from the edges of the network. Despite the rapid uptake of Long-power Wide-area Networks (LPWANs), it remains unclear how to organize the wireless sensor network in a scaleable and adaptive way. This paper introduces a hierarchical communication scheme that utilizes the new capabilities of Long-Range Wireless Sensor Networking technologies by combining them with broadly used 802.11.4-based low-range low-power technologies. The design of the hierarchical scheme is presented in detail along with the technical details on the implementation in real-world hardware platforms. A platform-agnostic software firmware is produced that is evaluated in real-world large-scale testbeds. The performance of the networking scheme is evaluated through a series of experimental scenarios that generate environments with varying channel quality, failing nodes, and mobile nodes. The performance is evaluated in terms of the overall time required to organize the network and setup a hierarchy, the energy consumption and the overall lifetime of the network, as well as the ability to adapt to channel failures. The experimental analysis indicate that the combination of long-range and short-range networking technologies can lead to scalable solutions that can service concurrently multiple applications