A Wireless Hay Bale Status Sensor Suite Using PCB Sensor Technology

2017 ◽  
Vol 2017 (DPC) ◽  
pp. 1-31
Author(s):  
Jeff D. Craven ◽  
Andrew W. Muscha ◽  
R. Chase Harrison ◽  
Markus A. R. Kreitzer ◽  
Robert N. Dean ◽  
...  
Keyword(s):  
Moisture Content ◽  
Spontaneous Combustion ◽  
Thermophilic Bacteria ◽  
Low Cost ◽  
The United States ◽  
Circuit Board ◽  
Sensor Technology ◽  
Moisture Content Level ◽  
Suitable Environment ◽  
Sensor Suite

The spontaneous combustion of curing hay bales poses serious safety and financial issues to farmers and ranchers across the United States and abroad. The primary cause of this spontaneous combustion is the baling of hay before it has adequately dried and reached a sufficiently low moisture content level. This inadequate drying is primarily due to the farmer allowing the hay to dry in the field after cutting for a given period of time. But unfortunately, this does not always ensure that the hay has sufficiently dried before baling. Spontaneous combustion of hay bales is due to a proliferation of thermophilic bacteria that thrive in a moist and hot environment. If the moisture content of hay is greater than 20%, it provides a suitable environment for mesophilic bacteria, which can heat the hay to as a high as 140°F. Although this is not problematic in and of itself, a 140°F hay bale is a suitable environment for the proliferation of thermophilic bacteria, which can further heat the hay to 170oF. At this temperature, the hay can spontaneous combust, destroying the hay and risking the loss of buildings, equipment, livestock and agricultural workers. To combat this problem, a low-cost, low-power, wireless hay bale status sensor suite has been developed so that the farmer can easily and safely monitor the conditions inside a curing hay bale, to give the farmer time to take action before the bale spontaneously combusts. The battery operated sensor suite has two sensors in contact with the hay inside the bale, a printed circuit board (PCB) moisture content sensor and a discrete temperature sensor. The extremely low-cost of the PCB moisture content sensor is what enables the practicality of the sensor suite. WiFi is used to transmit moisture content and temperature data to the farmer's smartphone when it comes within range. The sensor suite is placed inside the bale at the time of baling. After the bale has fully cured, in four to six weeks, the reusable sensor suite can be removed and used in a new bale.

A PCB Sensor for Magnetic Materials

2019 ◽  
Vol 2019 (DPC) ◽  
pp. 001323-001342
Author(s):  
Robert N. Dean ◽  
Lauren E. Beckingham
Keyword(s):  
Magnetic Materials ◽  
Printed Circuit Board ◽  
Low Cost ◽  
Complex Impedance ◽  
Corrosion Products ◽  
Physical Contact ◽  
Circuit Board ◽  
Sensor Technology ◽  
Printed Circuit ◽  
Surrounding Environment

Printed circuit board (PCB) sensors are a sensor technology where the layout of traces on a PCB has been optimized so that the traces electromagnetically interact with the surrounding environment. These types of sensors can be manufactured at very low cost using standard commercially available low-cost printed circuit board fabrication. Exposed conductive electrodes on the circuit board are useful for measuring the electrical conductivity of the surrounding environment, and these sensors have been used in applications such as salinity measurement and dissolved ion content measurement of aqueous solutions. Insulated interdigitated electrode sensors are useful for capacitively analyzing the surrounding environment, and these sensors have been used to detect the presence of liquid water and to measure the moisture content of substances in physical contact with the sensor. Additionally, by measuring the complex impedance of the capacitive sensor over a wide frequency range, information concerning the chemical composition of the substance in contact with the sensor can be determined. In addition to conducive and capacitive PCB sensors, the third type of PCB sensor would be an inductive sensor. Although it is challenging to realize 3D coils in PCB technology, planar inductors can be realized in a single Cu layer on a PCB, and insulated from the environment using a cover layer of polymeric solder mask. This type of electrode structure can inductively couple with magnetic materials in close proximity to the sensor. A variety of magnetic materials exist, including iron, nickel and cobalt. Additionally, many alloys of these elements are also magnetic. Of particular interest are corrosion products with magnetic properties, such as iron(III) oxide, Fe3O2, also known as common rust. A thin layer of iron(III) oxide powder deposited on the sensor's active area results in a measureable increase in the sensor's inductance. As such, an inductive PCB sensor could be a low-cost option for detecting the presence of some corrosion products in its operating environment.

A PCB Technology Moisture Content and Electrical Conductivity Sensor Probe for Agricultural and Horticultural Applications

2014 ◽  
Vol 2014 (DPC) ◽  
pp. 000984-001011
Author(s):  
Robert N. Dean ◽  
Elizabeth Guertal ◽  
Adam Newby ◽  
Glenn Fain
Keyword(s):  
Electrical Conductivity ◽  
Plant Growth ◽  
Moisture Content ◽  
Test Data ◽  
Printed Circuit Board ◽  
Low Cost ◽  
Circuit Board ◽  
Conductivity Sensor ◽  
Irrigation Volume ◽  
Sensor Probe

Commercial printed circuit board (PCB) technology affords the realization of low-cost sensor probes for agricultural and horticultural applications. Plant growth can be optimized when the soil (in field crop applications) or the substrate (in greenhouse crop applications) properties can be measured and properly adjusted. Two important parameters are moisture content and electrical conductivity. Measuring moisture content allows the grower to better time irrigation for most efficient crop growth. Accurate moisture content measurement also allows the grower to apply sufficient irrigation volume for optimum plant growth while avoiding excessive irrigation volume. Likewise, measuring the electrical conductivity reveals useful information regarding ions in the soil or substrate, which can be used to optimize the application of plant nutrients or manage soil salinity. Commercial soil probes are expensive, which limits their widespread use in commercial applications. PCB probes, on the other hand, can be very inexpensive and can quickly be redesigned to modify the form factor for different applications. These sensors make use of the materials and processes inherent in commercial PCB manufacturing, including the FR4 substrate, patterned Cu cladding and soldermask. The non-conductive E-glass FR4 substrate is used as the rigid backbone of the sensor probe. The patterned Cu cladding is used for electrodes and signal traces. The polymeric soldermask is used as a thin insulating and moisture barrier layer. With these materials, insulated fringing field sensors can be realized on the surface of the PCB to measure moisture content, while exposed metal pads on the surface can be used to measure electrical conductivity. Additionally, the PCB probe is directly compatible with the integration of any desired integrated electronic components. Furthermore, the turnaround time for a new PCB sensor design can be as little as 24 hours at modest cost, making this technology economically superior to traditional sensor technologies, such as silicon based MEMS, where it can take months to realize a new design and be very expensive. A prototype sensor probe has been designed, fabricated and evaluated. Test data is analyzed, compared with test data from traditional sensor probes and presented.

scholarly journals RF-Based Moisture Content Determination in Rice Using Machine Learning Techniques

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1875 ◽  
Author(s):  
Noraini Azmi ◽  
Latifah Munirah Kamarudin ◽  
Ammar Zakaria ◽  
David Lorater Ndzi ◽  
Mohd Hafiz Fazalul Rahiman ◽  
...  
Keyword(s):  
Random Forest ◽  
Moisture Content ◽  
Radio Frequency ◽  
Radio Frequency Identification ◽  
Low Cost ◽  
Machine Learning Techniques ◽  
Support Vector ◽  
Uhf Rfid ◽  
Input Feature ◽  
Moisture Content Level

Seasonal crops require reliable storage conditions to protect the yield once harvested. For long term storage, controlling the moisture content level in grains is challenging because existing moisture measuring techniques are time-consuming and laborious as measurements are carried out manually. The measurements are carried out using a sample and moisture may be unevenly distributed inside the silo/bin. Numerous studies have been conducted to measure the moisture content in grains utilising dielectric properties. To the best of authors’ knowledge, the utilisation of low-cost wireless technology operating in the 2.4 GHz and 915 MHz ISM bands such as Wireless Sensor Network (WSN) and Radio Frequency Identification (RFID) have not been widely investigated. This study focuses on the characterisation of 2.4 GHz Radio Frequency (RF) transceivers using ZigBee Standard and 868 to 915 MHz UHF RFID transceiver for moisture content classification and prediction using Artificial Neural Network (ANN) models. The Received Signal Strength Indicator (RSSI) from the wireless transceivers is used for moisture content prediction in rice. Four samples (2 kg of rice each) were conditioned to 10%, 15%, 20%, and 25% moisture contents. The RSSI from both systems were obtained and processed. The processed data is used as input to different ANNs models such as Support Vector Machine (SVM), K-Nearest Neighbour (KNN), Random Forest, and Multi-layer Perceptron (MLP). The results show that the Random Forest method with one input feature (RSSI_WSN) provides the highest accuracy of 87% compared to the other four models. All models show more than 98% accuracy when two input features (RSSI_WSN and RSSI_TAG2) are used. Hence, Random Forest is a reliable model that can be used to predict the moisture content level in rice as it gives a high accuracy even when only one input feature is used.

A PCB Sensor Suite for Monitoring the Effects of Annual Variations in Precipitation Rates on Alpine Lakes in Rocky Mountain National Park

2017 ◽  
Vol 2017 (DPC) ◽  
pp. 1-22
Author(s):  
Robert Dean ◽  
Isabella A. Oleksy ◽  
Daniel W. Bowker
Keyword(s):  
Low Cost ◽  
Rocky Mountain ◽  
Alpine Lakes ◽  
Rocky Mountain National Park ◽  
Circuit Board ◽  
Annual Variations ◽  
Electrode Sensor ◽  
Fringing Field ◽  
Field Sensor ◽  
Sensor Suite

Alpine Lakes are fragile ecosystems of immense beauty and value. They occur in high elevations and are often subjected to wide variations in annual precipitation rates. As such, their electrochemistry is affected by these annual variations in precipitation rates, which in turn, affects the entire ecosystem. Low-cost sensors for monitoring these changes will help in improving the management of these ecosystems. Low-cost Printed Circuit Board (PCB) sensors are being applied to many useful environmental and agricultural applications, including measuring soil moisture content, detecting pollution, monitoring drought conditions in estuaries, and monitoring for saltwater intrusion into coastal freshwater bodies. These sensors consist of a low-cost PCB with patterned Cu electrodes designed so that the circuit board electromagnetically interacts with the surrounding media, where its electrochemistry affects the measurable electrical impedance of the patterned traces. Exposed electrodes can be used to measure ion content in aqueous solutions from dissolved ionic compounds. Insulated electrodes can be used to measure moisture content of object and materials, or to identify dissolved ions in aqueous solution by searching for their relaxation frequency. In this multiyear study, a 2-layer PCB sensor suite consisting of a Au coated dual exposed electrode sensor on one side and a solder mask insulated interdigitated fringing field sensor on the opposite side is used. SMA connectors are attached to the opposite end of the sensor board for easy connection too instrumentation. The resistance of the exposed electrode sensor is measured using an Agilent 4192A LF Impedance Analyzer. The complex impedance of the fringing field sensor is measured using an Agilent E5061B Network Analyzer. For this study, PCB sensor technology is being investigated for monitoring the electrochemical properties of water samples from four alpine lake ecosystems in the Loch Vale Drainage at Rocky Mountain National Park. These alpine lakes are The Loch, Sky Pond, Andrews Tarn and Lake of Glass. Water samples were collected from these ecosystems in August of 2016, taken into the laboratory and tested with the PCB sensor suite to determine a baseline for the five year study.

scholarly journals A Technique for Detecting Moisture Absorption in Printed Circuit Boards

2020 ◽  
Vol 17 (1) ◽  
pp. 28-33
Author(s):  
Jeffery D. Craven ◽  
Ariel R. Oldag ◽  
Robert N. Dean
Keyword(s):  
Printed Circuit Boards ◽  
Printed Circuit Board ◽  
Moisture Absorption ◽  
Low Cost ◽  
Circuit Board ◽  
Sensor Technology ◽  
Circuit Boards ◽  
Liquid Form ◽  
Printed Circuit ◽  
Fringing Field

Abstract Most circuit boards operate in environments that have the potential to be exposed to moisture, either in vapor or liquid form. Because low-cost circuit boards can readily absorb moisture, this can lead to performance issues, reliability issues, and even catastrophic failure. However, it is difficult to detect if moisture absorption has occurred before the circuit board suffers a complete failure. To alleviate this issue, a fringing field capacitor was implemented in printed circuit board (PCB) technology and used to detect the absorption of moisture in the circuit board through the accompanying increase in capacitance. Prototype sensors were fabricated and immersed for 42 d, demonstrating an increase in capacitance of between 14% and 29%. This sensor technology can easily be added to circuit board designs because they use the standard materials and fabrication processes used in commercial PCB construction.

A Novel Wideband transition from Substrate Integrated Waveguide to Rectangular Waveguide

2020 ◽  
Vol 10 ◽  
Author(s):  
Keyur Mahant ◽  
Hiren Mewada ◽  
Amit Patel ◽  
Alpesh Vala ◽  
Jitendra Chaudhari
Keyword(s):  
Rectangular Waveguide ◽  
Printed Circuit Board ◽  
Low Cost ◽  
Single Layer ◽  
Circuit Board ◽  
Substrate Integrated Waveguide ◽  
Ka Band ◽  
Better Than ◽  
Millimeter Wave Circuits ◽  
Wideband Transition

Aim: In this article, wideband substrate integrated waveguide (SIW) and rectangular waveguide (RWG) transition operating in Ka-band is proposed Objective: In this article, wideband substrate integrated waveguide (SIW) and rectangular waveguide (RWG) transition operating in Ka-band is proposed. Method: Coupling patch etched on the SIW cavity to couple the electromagnetic energy from SIW to RWG. Moreover, metasurface is introduced into the radiating patch to enhance bandwidth. To verify the functionality of the proposed structure back to back transition is designed and fabricated on a single layer substrate using standard printed circuit board (PCB) fabrication technology. Results: Measured results matches with the simulation results, measured insertion loss is less than 1.2 dB and return loss is better than 3 dB for the frequency range of 28.8 to 36.3 GHz. By fabricating transition with 35 SRRs bandwidth of the proposed transition can be improved. Conclusion: The proposed transition has advantages like compact in size, easy to fabricate, low cost and wide bandwidth. Proposed structure is a good candidate for millimeter wave circuits and systems.

scholarly journals Comparative Study of the Properties of Wood Flour and Wood Pellets Manufactured from Secondary Processing Mill Residues

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2487
Author(s):  
Geeta Pokhrel ◽  
Yousoo Han ◽  
Douglas J. Gardner
Keyword(s):  
Moisture Content ◽  
Bulk Density ◽  
Raw Materials ◽  
Wood Flour ◽  
The United States ◽  
Red Maple ◽  
Wood Pellets ◽  
Secondary Processing ◽  
Material Costs ◽  
Mill Residues

The generation of secondary processing mill residues from wood processing facilities is extensive in the United States. Wood flour can be manufactured utilizing these residues and an important application of wood flour is as a filler in the wood–plastic composites (WPCs). Scientific research on wood flour production from mill residues is limited. One of the greatest costs involved in the supply chain of WPCs manufacturing is the transportation cost. Wood flour, constrained by low bulk densities, is commonly transported by truck trailers without attaining allowable weight limits. Because of this, shipping costs often exceed the material costs, consequently increasing raw material costs for WPC manufacturers and the price of finished products. A bulk density study of wood flour (190–220 kg/m3) and wood pellets (700–750 kg/m3) shows that a tractor-trailer can carry more than three times the weight of pellets compared to flour. Thus, this study focuses on exploring the utilization of mill residues from four wood species in Maine to produce raw materials for manufacturing WPCs. Two types of raw materials for the manufacture of WPCs, i.e., wood flour and wood pellets, were produced and a study of their properties was performed. At the species level, red maple 40-mesh wood flour had the highest bulk density and lowest moisture content. Spruce-fir wood flour particles were the finest (dgw of 0.18 mm). For all species, the 18–40 wood flour mesh size possessed the highest aspect ratio. Similarly, on average, wood pellets manufactured from 40-mesh particles had a lower moisture content, higher bulk density, and better durability than the pellets from unsieved wood flour. Red maple pellets had the lowest moisture content (0.12%) and the highest bulk density (738 kg/m3). The results concluded that the processing of residues into wood flour and then into pellets reduced the moisture content by 76.8% and increased the bulk density by 747%. These material property parameters are an important attempt to provide information that can facilitate the more cost-efficient transport of wood residue feedstocks over longer distances.

scholarly journals Possibilities of Decreasing Hygroscopicity of Resonance Wood Used in Piano Soundboards Using Thermal Treatment

2021 ◽  
Vol 11 (2) ◽  
pp. 475
Author(s):  
Petr Zatloukal ◽  
Pavlína Suchomelová ◽  
Jakub Dömény ◽  
Tadeáš Doskočil ◽  
Ginevra Manzo ◽  
...  
Keyword(s):  
Moisture Content ◽  
Conversion Efficiency ◽  
Dynamic Modulus ◽  
Moisture Sorption ◽  
Acoustical Properties ◽  
Longitudinal Dynamic ◽  
Moisture Content Level ◽  
Longitudinal Sound Velocity ◽  
Tan Δ ◽  
Resonance Wood

This article presents the possibilities of decreasing moisture sorption properties via thermal modification of Norway spruce wood in musical instruments. The 202 resonance wood specimens that were used to produce piano soundboards have been conditioned and divided into three density groups. The first specimen group had natural untreated properties, the second was thermally treated at 180 °C, and the third group was treated at 200 °C. All specimens were isothermally conditioned at 20 °C with relative humidity values of 40, 60, and 80%. The equilibrium moisture content (EMC), swelling, and acoustical properties, such as the longitudinal dynamic modulus (E’L), bending dynamic modulus (Eb), damping coefficient (tan δ), acoustic conversion efficiency (ACEL), and relative acoustic conversion efficiency (RACEL) were evaluated on every moisture content level. Treatment at 180 °C caused the EMC to decrease by 36% and the volume swelling to decrease by 9.9%. Treatment at 200 °C decreased the EMC by 42% and the swelling by 39.6%. The 180 °C treatment decreased the value of the longitudinal sound velocity by 1.6%, whereas the treatment at 200 °C increased the velocity by 2.1%. The acoustical properties EL′, Eb, ACEL, and RACEL were lower due to the higher moisture content of the samples, and only the tanδ increased. Although both treatments significantly affected the swelling and EMC, the treatment at 180 °C did not significantly affect the acoustical properties.

scholarly journals Highly Compact Through-Wire Microstrip to Empty Substrate Integrated Coaxial Line Transition

2021 ◽  
Vol 11 (15) ◽  
pp. 6885
Author(s):  
Marcos D. Fernandez ◽  
José A. Ballesteros ◽  
Angel Belenguer
Keyword(s):  
Printed Circuit Board ◽  
Low Cost ◽  
Coaxial Line ◽  
Circuit Board ◽  
Central Layer ◽  
Printed Circuit ◽  
Integrated Technology ◽  
Low Profile ◽  
The Many ◽  
High Degree

Empty substrate integrated coaxial line (ESICL) technology preserves the many advantages of the substrate integrated technology waveguides, such as low cost, low profile, or integration in a printed circuit board (PCB); in addition, ESICL is non-dispersive and has low radiation. To date, only two transitions have been proposed in the literature that connect the ESICL to classical planar lines such as grounded coplanar and microstrip. In both transitions, the feeding planar lines and the ESICL are built in the same substrate layer and they are based on transformed structures in the planar line, which must be in the central layer of the ESICL. These transitions also combine a lot of metallized and non-metallized parts, which increases the complexity of the manufacturing process. In this work, a new through-wire microstrip-to-ESICL transition is proposed. The feeding lines and the ESICL are implemented in different layers, so that the height of the ESICL can be independently chosen. In addition, it is a highly compact transition that does not require a transformer and can be freely rotated in its plane. This simplicity provides a high degree of versatility in the design phase, where there are only four variables that control the performance of the transition.

scholarly journals 662 PAP Therapy: A Review of Resources for the Uninsured during COVID-19

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A259-A259
Author(s):  
Melissa Malinky ◽  
Abigail Oberla ◽  
Meena Khan ◽  
M Melanie Lyons
Keyword(s):  
Low Income ◽  
Web Search ◽  
Low Cost ◽  
Wait Time ◽  
The United States ◽  
Fixed Cost ◽  
United States Census ◽  
Lower Socioeconomic ◽  
Increased Risk ◽  
Available Resources

Abstract Introduction In 2019, the United States Census estimated 8% (26.1 million) people were without health insurance. Further, an estimated 3.5 million people became/remained uninsured from COVID-19-related job losses. Patients with OSA that belong to a lower socioeconomic status (SES) are less likely to have access to healthcare and may be under or uninsured. Untreated OSA can lead to increased risk of symptoms and associated co-morbidities. Resources to help the uninsured to obtain PAP therapy were available pre-COVID, including two main sources, American Sleep Apnea Association (ASAA) and our local branch serving central Ohio, The Breathing Association. However, the COVID pandemic limited access or closed these programs. Our Sleep Medicine clinics saw 148 uninsured OSA patients between March-December, 2020. Given these difficulties, we re-evaluated available resources for the uninsured. Methods We conducted a search for current low cost ($100 or less) PAP therapy options for the uninsured, March 15, 2020-December 3, 2020, by: (1) contacting pre-COVID-19 resources, including Durable Medical Equipment (DME) providers, (2) consulting social work, and (3) completing a librarian assisted web-search not limited to PubMed, Embase, CINAHL for academic related articles and electronic searches using a combination of English complete word and common keywords: OSA, PAP, uninsured, no insurance, cheap, medically uninsured, resources, self-pay, low-income, financial assistance, US. Resources such as private sellers were not investigated. Results During COVID-19, assistance for PAP machines/supplies have closed or required a protracted wait-time. Options including refurbished items range from low, one-time fixed cost or income-based discounts from: one local charity (Joint Organization for Inner-City Needs) and DME (Dasco), and four national entities (ASAA, Second Wind CPAP, Reggie White Foundation, CPAP Liquidators). An Electronic Health Record-based tool was developed and distributed to increase provider awareness of pandemic available resources. Conclusion Untreated OSA is associated with increased risk of cardiovascular co-morbidities. Access and cost may limit treatment in OSA patients from a lower SES. The COVID-19 pandemic has shuttered programs providing discount PAP and supplies, leaving fewer resources for these patients, thus further widening this health care disparity. Alternatives are needed and current resources are not easily accessible for providers and patients. Support (if any):

Sign in / Sign up

Export Citation Format

Share Document