Moisture estimation for precision agriculture through RF sensing

Convenient, non-obtrusive, low-cost, and accurate sensing of fruit moisture content is crucial for the scientific studies of Pomology and Viticulture and their associated agriculture. It can provide early indicators of yield estimation and crop health as well as providing data for food production and precision farming systems. With a focus on grapes, we introduce SING, a scheme that senses grape moisture content by utilizing RF signals but without physical contact with the fruit. In this thesis, we extend the investigation of the theoretical relationship between the dielectric properties and the moisture content of agricultural products to establish a sensing model in the 5 GHz band. To make the work practical, we are first to measure the dielectric properties of grape bunches (not individually as that would be destructive), presenting a unique measurement challenge as internal grapes are hidden. In doing so, we demonstrate that our technique precisely estimates moisture content to a high degree of accuracy (90%). Current RF sensing models to estimate moisture are destructive; they require samples to be constrained in containers. Our work is first to dispense with such impracticalities, and, without contact with the object, accurately measures non-uniform grape clusters in open space. We demonstrate that SING is superior to existing work in its ability to accurately measure the dielectric properties of non-uniform fruit objects and test this through both lab-based experimentation and preliminary outdoor vineyard tests. We also examine the transferability of SING’s approach to real-world scenarios.Open Acces

Underground Phased Arrays and Beamforming Applications

This chapter presents a framework for adaptive beamforming in underground communication. The wireless propagation is thoroughly analyzed to develop a model using the soil moisture as an input parameter to provide feedback mechanism while enhancing the system performance. The working of array element in the soil is analyzed. Moreover, the effect of soil texture and soil moisture on the resonant frequency and return loss is studied in detail. The wave refraction from the soil–air interface highly degrades the performance of the system. Furthermore, to beam steering is done to achieve high gain for lateral component improving the UG communication. The angle enhancing the lateral wave depends upon dielectric properties and usually ranges from 0∘ to 16∘. These dielectric properties change with the change in soil moisture and soil texture. It is shown from the experiments that optimal UG lateral angle is high at lower soil moisture readings and decreases with decrease in soil moisture. A planar structure of antenna array and different techniques for optimization are proposed for enhanced soil moisture adaptive beamforming. UG channel impulse response is studied from the beamforming aspect to identify the components of EM waves propagating through the soil. An optimum steering method for beamforming is presented which adapts to the changing values of soil moisture. Finally, the limitations of UG beamforming are presented along with the motivation to use it

Computerized data acquisition system for tractor field performance

A John Deere farm tractor model 4430 H was instrumented to monitor forward velocity, slip, area operated by implement, rate of fuel consumption, total fuel consumption, theoretical field time and total field time. Two magnetic pickups each with a ferrous gear were used to monitor the angular velocity of the right front and rear wheels. The fuel consumption was monitored with a single turbine flow transducer. An intermediate float tank system was used to accommodate the return fuel from the injector pump and injectors. A micro switch was also used to detect the operating position of the implement. The transducers attached to the tractor did not require any major alteration of the tractor system or restrict its operation;A single board microcomputer tractor performance monitor based on Intel 8035 single chip microcomputer was developed to monitor the inputs of the transducers and controls and to calculate and display the values of the monitored parameters. The developed tractor performance monitor had the following capabilities: (1) 2048 8-bit words of program memory; (2) 64 8-bit words of data memory; (3) one 8-bit data input port; (4) two 3-digit and three 2-digit displays; (5) single step unit; (6) single 5-volt power supply; and (7) expansion capabilities with (i) 2048 8-bit words of program memory, (ii) 256 8-bit words of data memory, and (iii) virtually unlimited input/output ports;The instrumented tractor was tested with a chisel plow and a tandem disc harrow in a slightly wet combine harvested corn field. All the transducers functioned properly and proved to be reliable under field conditions. The system also was easy and simple to use without restricting operator movement. The operator starts and stops the data acquisition of the monitor with an easily-reached switch

RISE: Robust Wireless Sensing Using Probabilistic and Statistical Assessments

Peer reviewe

Hydromodus: An Autonomous Underwater Vehicle

Hydromodus is a student-led multidisciplinary project conceived by Jordan Read designed to provide a low-cost modular hardware and software solution for researchers and scientists. For the scope of the Senior Project class, it is designed to be a baited remote underwater vehicle (BRUV), but the platform is highly modifiable and open-source

A Survey on Subsurface Signal Propagation

Wireless Underground Communication (WUC) is an emerging field that is being developed continuously. It provides secure mechanism of deploying nodes underground which shields them from any outside temperament or harsh weather conditions. This paper works towards introducing WUC and give a detail overview of WUC. It discusses system architecture of WUC along with the anatomy of the underground sensor motes deployed in WUC systems. It also compares Over-the-Air and Underground and highlights the major differences between the both type of channels. Since, UG communication is an evolving field, this paper also presents the evolution of the field along with the components and example UG wireless communication systems. Finally, the current research challenges of the system are presented for further improvement of the WUCs

Fleets of robots for environmentally-safe pest control in agriculture

Feeding the growing global population requires an annual increase in food production. This requirement suggests an increase in the use of pesticides, which represents an unsustainable chemical load for the environment. To reduce pesticide input and preserve the environment while maintaining the necessary level of food production, the efficiency of relevant processes must be drastically improved. Within this context, this research strived to design, develop, test and assess a new generation of automatic and robotic systems for effective weed and pest control aimed at diminishing the use of agricultural chemical inputs, increasing crop quality and improving the health and safety of production operators. To achieve this overall objective, a fleet of heterogeneous ground and aerial robots was developed and equipped with innovative sensors, enhanced end-effectors and improved decision control algorithms to cover a large variety of agricultural situations. This article describes the scientific and technical objectives, challenges and outcomes achieved in three common crops

The Ryggfonn project. Description of instrumentation and data registration system

The Ryggfonn avalanche path has been instrumented to measure: deflections on a 6 m high steel mast mounted at top of the test embankment by means of weldable strain gauges; wind speed of powder snow fronts by means of a three direciton propeller based wind speed sensor; snow pressure forces on an 18 cm diameter strain gauge based load cell mounted at top of the test embankment; axial tension in three high tension cables crossing the avalanche path by means of strain gauge based in-line load cells; snow pressure forces acting upon a 4.5 m high concrete structure by means of three strain gauge based load cells totally covering the wall facing the avalanche; vertical vibration velocity by means of a seismometer mounted at the concrete structur

Application of advanced technology to space automation

Automated operations in space provide the key to optimized mission design and data acquisition at minimum cost for the future. The results of this study strongly accentuate this statement and should provide further incentive for immediate development of specific automtion technology as defined herein. Essential automation technology requirements were identified for future programs. The study was undertaken to address the future role of automation in the space program, the potential benefits to be derived, and the technology efforts that should be directed toward obtaining these benefits