Abstract

Detection of color change is an important tool used in several analytical chemistry processes in various industries such as biomedical, diagnostics, agriculture, food processing, and so on. In this study, we present an automated color detection system to perform qualitative analysis of liquid reagents. Many of the available techniques for colorimetric applications make use of expensive, high-resolution digital cameras. We have developed a simple low-cost system based on a light emitting diode (LED) and light-dependent resistor (LDR) pair to obtain information about the color of a liquid reagent. This system has been compared with a camera-based system for color detection. The LED-LDR system provides information about the color of an object by obtaining relative intensities of red, green, and blue (RGB) light reflected by the object in a sequential process. The system was tested by obtaining color information for different concentrations of potassium permanganate solution and by determining the endpoint of a titration experiment. This versatile system can be used for many other colorimetric measurements, for example, the amount of dissolved ammonia in water using Nesslers reagent (potassium tetraiodomercurate).

Abstract

The growing need for localization has created an array of alternative approaches to GNSS, based on Wi-Fi, Bluetooth, Ultra-Wideband, etc. Long Range Wide Area Network (LoRaWAN) is one such technology that has garnered tremendous attention due to its low power and long-range capabilities. Many attempts to achieve localization using LoRaWAN have been made till now, based on a variety of techniques such as Angle of Arrival (AoA), Time Difference of Arrival (TDoA), Received Signal Strength Index (RSSI). In this paper, we present a novel, standalone localization approach by developing a collaborative, TDoA-based methodology using LoRaWAN. The server determines the target node location by means of TDoA measurements from the target node to the gateways. The introduction of an additional stationary node allows the synchronization of the gateways without utilizing GNSS, either inbuilt or external. The cooperation between target node, synchronization node and server, is the innovative feature which makes this approach attractive for GNSS-free localization. Further, we explore the effects of timing resolution, time-on-air, and duty cycle constraints on the localization error. Finally, the distribution of error in a triangle of gateways situated approximately 8.6 kilometers apart is simulated in ideal Line of Sight (LoS) conditions, showing the maximum error to be around 23 meters

Abstract

Methods and apparatus for modulating light using a tunable light modulation device . The tunable light modulation devices comprises an elastomer structure including at least one elastomer layer , a compliant electrode network of con ducting fibers arranged on a first surface of the at least one elastomer layer , a patterned electric conductor arranged on a second surface of the at least one elastomer layer opposite the first surface . The patterned electric conductor includes a plurality of individually - addressable sections , and the com pliant electrode network is configured to compress the at least one elastomer layer in the presence of an electric field between the compliant electrode network and one or more of the individually - addressable sections of the patterned elec tric conductor to produce a voltage - dependent roughening of the at least one elastomer layer .

Abstract

Muscle weakening is a common consequence of stroke and can result in a reduction in physical activity of the affected body part. Therapy includes a range of physical exercises that will help the patients restore and build physical strength, endurance, flexibility, balance, and stability. In order to analyze and recognize the activity and movement of hands while performing these exercises, we have developed a 4 × 4 flexible pressure sensor matrix to quantize the performance and progress of a patient undergoing physiotherapy. We have also developed an artificial intelligence (AI) based algorithm to determine the accuracy of positioning by the patients. Experimental results demonstrate that the algorithm gives a mean error of 0.103 cm in detecting the position of load, compared to a mean error of 0.704 cm using mathematical analysis. With this system, a patient can be asked to move a weight to a particular location (as part of regular physiotherapy) and the pressure sensor matrix can be used to calculate error in positioning along with the time taken to complete the task. Advantages of the proposed pressure sensor matrix are cost effectiveness, facile fabrication, high sensitivity, robustness and flexibility

Abstract

An Electric Vehicle (EV) charger, also called Electric Vehicle Charging Station (EVCS) is an infrastructure element that supplies electrical energy for recharging EVs. The paper focuses on the design and fabrication of two-wheeler (escooter) electric vehicle charging equipment. Considering the future scenario of mass privatization of EV two-wheelers on Indian roads, the outline discusses the product design based on fabricability, affordability, and ability to mass manufacture. The proposed architecture follows the Level 2 charging standards (240 Volts), and is based on the open charge point protocol (OCPP). The suggested EVCS is constructed considering the safety prerequisites of system administrators, installers, consumers, government agencies and others. The design of EVCS links to three industries: equipment manufacturers, software industry and electric power networks. This paper presents design considerations by elaborating the hardware, software, and protocols followed to design the Level 2 charging standard EVCS. Index Terms—Electric Vehicle (EV), Electric Vehicle Charge Station (EVCS), Web Sockets, Open Charge Point Protocol (OCPP), Level 2 EV Charging

Abstract

The ever-growing need for surveillance over various geographical locations has necessitated the development of novel monitoring approaches. While drones are still considered the most suitable aerial surveillance equipment, new techniques based on use of kites such as kite aerial photography (KAP) are becoming popular. This paper deals with one such novel approach, termed as KiteCam, which provides a low-cost and versatile method of performing local aerial surveillance for a prolonged period. The camera, processor, battery and power management module have been designed and fabricated such that the total weight of the system is approximately 42 grams. Hence, the system is light enough to be carried by most kites under normal weather conditions, thus offering a wide variety of applications with minimal energy consumption and concealed surveillance options. The test flights have been successfully conducted and observed in terms of stability and duration. The images obtained from the flight tests have been analyzed and verified for consistency and clarity. Finally, some modifications have also been mentioned regarding the future generations of the device.

Abstract

The ever-growing need for surveillance over various geographical locations has necessitated the development of novel monitoring approaches. While drones are still considered the most suitable aerial surveillance equipment, new techniques based on use of kites such as kite aerial photography (KAP) are becoming popular. This paper deals with one such novel approach, termed as KiteCam, which provides a low-cost and versatile method of performing local aerial surveillance for a prolonged period. The camera, processor, battery and power management module have been designed and fabricated such that the total weight of the system is approximately 42 grams. Hence, the system is light enough to be carried by most kites under normal weather conditions, thus offering a wide variety of applications with minimal energy consumption and concealed surveillance options. The test flights have been successfully conducted and observed in terms of stability and duration. The images obtained from the flight tests have been analyzed and verified for consistency and clarity. Finally, some modifications have also been mentioned regarding the future generations of the device.

Abstract

In this work, a large area, low cost and flexible polymer/paper-based double touch mode capacitive pressure sensor is demonstrated. Garage fabrication processes are used which only require cutting, taping and assembly of aluminum (Al) coated polyimide (PI) foil, PI tape and double-sided scotch tape. The presented pressure sensor operates in different pressure regions i.e. normal (0 to 7.5 kPa), transition (7.5 to 14.24 kPa), linear (14.24 to 54.9 kPa) and saturation (above 54.9 kPa). The advantages of the demonstrated double touch mode capacitive pressure sensors are low temperature drift, long linear range, high pressure sensitivity, precise pressure measurement and large die area. The linear output along with a high sensitivity range (14.24 to 54.9 kPa pressure range) of the sensor are utilized to wirelessly control the movement of a robotic arm with precise rotation and tilt movement capabilities.

Abstract

Windows whose transmittance can be modified by an applied voltage have previously been fabricated from soft, transparent elastomers sandwiched between ITO coated glass and a compliant, silver nanowire top electrode.1 In this contribution we extend the capabilities of the tunable window so that the optical transmittance can be varied spatially over the window according to voltage signals applied to different segments of the back electrode of the window, defined by patterning of individually addressable electrodes. The actuation signals are controlled using TTL-level input signals applied to high voltage switches. We also show that the spatially tunable window can be fabricated on a flexible substrate, such as PET, and the optical transmittance is not affected by bending of the substrate. The use of a polymer substrate not only increases possible applications of this class of voltage controlled light modulation device but also has the potential of reducing cost at an industrial scale by replacing more costly ITO coated glass substrate.

Abstract

We present detailed shape-based analyses to compare the performance of metal foil-based capacitive pressure sensors based on the shape of the diaphragm (top electrode). We perform a detailed analysis on the use of new material and deflection in various shaped diaphragms to act as a performance indicator for pressure-based capacitive sensors. A low-cost, recyclable, and readily available material is used to present an alternative to the expensive materials used in conventional pressure sensors. Diaphragms of five different shapes (circle, ellipse, pentagon, square, and rectangle) are fabricated and analyzed. Mathematical, FEM, and experimental tests are performed for capacitive sensors fabricated in five different shapes. The mathematically calculated deflection for each shaped diaphragm is compared with the results of the corresponding FEM simulations. Two different experiments are performed to verify …