Development of a Solar-Powered Integrated Wireless Soil Moisture Meter

In this study, we developed a solar-powered integrated wireless soil moisture meter that can easily measure in situ soil moisture, soil temperature, and hydrogen potential (pH) using nature\u27s solar energy. Knowledge of soil moisture content and other relevant soil-specific parameters is essential for irrigation scheduling, fertilizer selection, and fertigation. Also, considering that the electricity supply in some developing countries is either erratic or unavailable, this research aims to bridge the gap in electricity availability and ease of measurement and integrate more soil-specific parameters. The sensor system was developed using the frequency domain (FD) technique for fast response. These parameters were measured sequentially at an interval of about 5 seconds, with the readings displayed simultaneously on a Bluetooth-connected device (e.g., an Android phone) located about 50 meters away from the developed system. The different sensors are classified and adequately labeled to identify the parameter to be measured. The performance evaluation carried out indicated a reasonably functioning device that is cost-effective. The results obtained showed that the system was resourceful as it not only measured the parameters of interest (soil moisture, temperature, and pH) but also gave a prompt response in measurement and transmission. Overall, the developed wireless soil moisture meter provides instantaneous data on pH, moisture, and temperature circulation across soil layers. The system is promising as it can be integrated into large-scale automated irrigation systems for agricultural lands

Electromagnetic Characteristics of the Soil

The electromagnetic characteristics of the soil are discussed in this chapter. The characteristics of porous bedrock, soil medium, and impacts of rain attenuations are also presented. The models of dielectric soil properties are studied with a rigorous focus on the constitutive parameters of subsurface soil medium. Moreover, the permittivity and wavenumber in soil are explained. In addition, the frequency-dependent dielectric properties such as dispersion in soil, absorption characteristic, and penetration depth versus frequency are reviewed. Furthermore, the effective permittivity of soil–water mixture for through-the soil-propagation mechanism is analyzed thoroughly

Impacts of Soil Type and Moisture on the Capacity of Multi-Carrier Modulation in Internet of Underground Things

Unique interactions between soil and communication components in wireless underground communications necessitate revisiting fundamental communication concepts from a different perspective. In this paper, capacity profile of wireless underground (UG) channel for multi-carrier transmission techniques is analyzed based on empirical antenna return loss and channel frequency response models in different soil types and moisture values. It is shown that data rates in excess of 124 Mbps are possible for distances up to 12 m. For shorter distances and lower soil moisture conditions, data rates of 362 Mbps can be achieved. It is also shown that due to soil moisture variations, UG channel experiences significant variations in antenna bandwidth and coherence bandwidth, which demands dynamic subcarrier operation. Theoretical analysis based on this empirical data show that by adaption to soil moisture variations, 180% improvement in channel capacity is possible when soil moisture decreases. It is shown that compared to a fixed bandwidth system; soilbased, system and sub-carrier bandwidth adaptation leads to capacity gains of 56%-136%. The analysis is based on indoor and outdoor experiments with more than 1; 500 measurements taken over a period of 10 months. These semi-empirical capacity results provide further evidence on the potential of underground channel as a viable media for high data rate communication and highlight potential improvements in this area

Variable Rate Applications in Decision Agriculture

In this chapter, the variable rate applications (VRA) are presented for the field of decision agriculture. The characteristics of VRA control systems are described along with control hardware. Different types of VRA systems are discussed (e.g., liquid VRA systems and dry VRA systems). A case study is also explored in this regard. Moreover, recent advances and future trends are also outlined. Accordingly, a sustainable variable-rate irrigation scheduling is studied where different hardware and software component of the cyber-physical system are considered. Finally, chapter is concluded with a novel sensor deployment methodology

Signals in the Soil: Underground Antennas

Antenna is a major design component of Internet of Underground Things (IOUT) communication system. The use of antenna, in IOUT, differs from traditional communication in that it is buried in the soil. Therefore, one of the main challenges, in IOUT applications, is to establish a reliable communication. To that end, there is a need of designing an underground-specific antenna. Three major factors that can impact the performance of a buried antenna are: (1) effect of high soil permittivity changes the wavelength of EM waves, (2) variations in soil moisture with time affecting the permittivity of the soil, and (3) difference in how EM waves propagate during aboveground (AG) and underground (UG) communications. For the third challenge above, it is to be noted that lateral waves are dominant component in EM during UG2UG communication and suffer lowest attenuation as compared to other, direct and reflected, components. Therefore, antennas used for over-the-air (OTA) communication will not be suitable for UG communication because of impedance mismatch. This chapter focuses on developing a theoretical model for understanding the impact of soil on antenna by conducting experiments in different soil types (silty clay loam, sandy, and silt loam soil) and indoor testbed. The purpose of the model is to predict UG antenna resonance for designing efficient communication system for IOUT. Based on the model a wideband planar antenna is designed considering soil dispersion and soil–air interface reflection effect which improves the communication range five times from the antennas designed only for the wavelength change in soil. Furthermore, it also focuses on developing an impedance model to study the effect of changing wavelength in underground communication. It is also discussed how soil–air interface and soil properties effect the return loss of dipole antenna

Decision Agriculture

In this chapter, the latest developments in the field of decision agriculture are discussed. The practice of management zones in digital agriculture is described for efficient and smart faming. Accordingly, the methodology for delineating management zones is presented. Modeling of decision support systems is explained along with discussion of the issues and challenges in this area. Moreover, the precision agriculture technology is also considered. Moreover, the chapter surveys the state of the decision agriculture technologies in the countries such as Bulgaria, Denmark, France, Israel, Malaysia, Pakistan, United Kingdom, Ukraine, and Sweden. Finally, different field factors such as GPS accuracy and crop growth are also analyzed

Current Advances in Internet of Underground Things

The latest developments in Internet of Underground Things are covered in this chapter. First, the IOUT Architecture is discussed followed by the explanation of the challenges being faced in this paradigm. Moreover, a comprehensive coverage of the different IOUT components is presented that includes communications, sensing, and system integration with the cloud. An in-depth coverage of the applications of the IOUT in various disciplines is also surveyed. These applications include areas such as decision agriculture, pipeline monitoring, border control, and oil wells

Signals in the Soil: An Introduction to Wireless Underground Communications

In this chapter, wireless underground (UG) communications are introduced. A detailed overview of WUC is given. A comprehensive review of research challenges in WUC is presented. The evolution of underground wireless is also discussed. Moreover, different component of UG communications is wireless. The WUC system architecture is explained with a detailed discussion of the anatomy of an underground mote. The examples of UG wireless communication systems are explored. Furthermore, the differences of UG wireless and over-the-air wireless are debated. Different types of wireless underground channel (e.g., In-Soil, Soil-to-Air, and Air-to-Soil) are reported as well

Event and Time-Triggered Control Module Layers for Individual Robot Control Architectures of Unmanned Agricultural Ground Vehicles

Automation in the agriculture sector has increased to an extent where the accompanying methods for unmanned field management are becoming more economically viable. This manifests in the industry’s recent presentation of conceptual cab-less machines that perform all field operations under the high-level task control of a single remote operator. A dramatic change in the overall workflow for field tasks that historically assumed the presence of a human in the immediate vicinity of the work is predicted. This shift in the entire approach to farm machinery work provides producers increased control and productivity over high-level tasks and less distraction from operating individual machine actuators and implements. The final implication is decreased mechanical complexity of the cab-less field machines from their manned counter types. An Unmanned Agricultural Ground Vehicle (UAGV) electric platform received a portable control module layer (CML) which was modular and able to accept higher-level mission commands while returning system states to high-level tasks. The simplicity of this system was shown by its entire implementation running on microcontrollers networked on a Time-Triggered Controller Area Network (TTCAN) bus. A basic form of user input and output was added to the system to demonstrate a simple instance of sub-system integration. In this work, all major levels of design and implementation are examined in detail, revealing the ‘why’ and ‘how’ of each subsystem. System design philosophy is highlighted from the beginning. A state-space feedback steering controller was implemented on the machine utilizing a basic steering model found in literature. Finally, system performance is evaluated from the perspectives of a number of disciplines including: embedded systems software design, control systems, and robot control architecture. Recommendations for formalized UAGV system modeling, estimation, and control are discussed for the continuation of research in simplified low-cost machines for in-field task automation. Additional recommendations for future time-triggered CML experiments in bus robustness and redundancy are discussed. The work presented is foundational in the shift from event-triggered communications towards time-triggered CMLs for unmanned agricultural machinery and is a front-to-back demonstration of time-triggered design. Advisor: Santosh K. Pitl

Reconfiguration dynamique et simulation fine modélisée au niveau de transaction dans les réseaux de capteurs sans fil hétérogènes matériellement-logiciellement

Cette thèse porte premièrement sur la reconfiguration dynamique et la simulation hétérogène dans les Réseaux des Capteurs sans Fil. Ces réseaux sont constitués d une multitude de systèmes électroniques communicants par radio-fréquence, très contraints en énergie. La partie de communication radio entre ces nœuds est la plus consommatrice. C est pourquoi la minimisation du temps effectif est désirée. On a implémenté une solution qui consiste à envoyer au nœud un fichier de reconfiguration codé utilisant un langage de programmation haut niveau (MinTax). Le nœud sera capable de compiler ce fichier et générer le code object associé à son architecture, in-situ. Grâce au caractère abstrait du MinTax, plusieurs architectures matérielles et systèmes d exploitation sont visés. Dans un deuxième temps, ce travail de thèse est lié au simulateur de réseaux de capteurs IDEA1TLM.IDEA1TLM permet de prédire quels circuits et configurations sont les plus adéquats à une application sans fil donnée. Ce simulateur a été amélioré pour permettre la simulation rapide des systèmes électroniques matériellement différents dans le même réseau ainsi que le logiciel présent sur les noeuds. Mots clés : Reconfiguration dynamique, Compilation in-situ, MinTax, Hétérogénéité, IDEA1TLM.This PhD thesis concerns the dynamic reconfiguration and simulation of heterogeneous Wireless Sensor Networks. These networks consist of a multitude of electronic units called ?nodes ?, which communicate through a radio interface. The radio interface is the most power-consuming on the node. This is why the minimisation of the radio-time would lead to improved energy efficiency. We have implemented a software solution which consists in sending an update to a node which is coded in a high-level language (MinTax). This file is compiled by the node and machine code is generated for the target hardware architecture. Owing to the abstract nature of MinTax, multiple hardware architectures. as well as operating systems are supported. As a second part of this PhD, work has been focused on a network simulator called IDEATLM.IDEA1TLM allows us to predict which circuits and configurations are the most appropriate for a given task. This solution has been improved to allow a faster simulation of electronic systems which are different from a hardware standpoint, yet part of the same network, as well as to model the actual software running on them.LYON-Ecole Centrale (690812301) / SudocSudocFranceF