Papers by Keyword: Low Cost

Abstract: The cost of prosthetics is a complex and multifaceted problem affecting individuals in need of these life-changing devices. Myoelectric prosthetics that can significantly improve the quality of life of individuals with upper limb amputations cost around $4000(6,105,000 naira) to $10,000(15,262,500 naira) for even the most basic models, this is a challenge for individuals in developing and underdeveloped countries as they cannot afford these prostheses. However, low-cost prosthetics are mostly non-functional with the functional prosthetic solutions having limited range of movement. Hence, the main objective of this research was to create a functional and affordable upper limb prosthetic device that can respond to muscle signals, enabling natural hand movement. Myoelectric prosthetic hands are artificial limbs controlled by electrical signals generated by the user's residual muscles. These signals are detected by electrodes placed on the skin and translated into movements by a microprocessor within the prosthesis. The myoelectric prosthetic was fabricated using 3D modeling, and the hand components were printed using poly-lactic acid (PLA) to address this issue. The design incorporated five individual fingers, each with multiple segments, to replicate the structure of the human hand. Servo motors were strategically positioned to actuate the finger movements based on myoelectric signals captured by surface electrodes placed on the user’s forearm. The electrical system consisted of an Arduino nanomicrocontroller, an electromyography (EMG) sensor, and various power management components. Calibration procedures were implemented to establish appropriate thresholds for distinguishing between hand movements, such as palm open and grab. The system allows for wider range of movement due to its 5 DOFs (degree of freedom). The system and it also exhibits an average response speed of 1.845 seconds. This cost-effective prosthetic hand would improve the quality of life for amputees and also increase accessibility and affordability to amputees, generally impacting health globally. This design breaks new grounds in low-cost prosthetics by focusing on the use of locally sourced materials and functional control system for the movement of the hand through the use of a simple 3-D printing technology and easily accessible materials precisely assembled together to replace the complex and expensive ones in the market.

Abstract: Abstract. Smallholder farms provide a significant share of the world's food supply. Smallholder farmers can cultivate crops more consistently throughout the year when using solar water pumps, which offer a dependable source of irrigation. However, the upfront capital cost and efficiency are major barriers to widespread adoption. This paper aimed to design a cost-effective and efficient DC-DC converter for small-scale irrigation farming in the Dangishta, Amhara region of Ethiopia, focusing on a direct solar water pump system using a SEPIC-based DC-DC converter. The system directly supplies power to a 100 W/24 V brushless DC pump, with a 120 W/24 V/5 A optimized SEPIC converter. A PLECS simulation was conducted to understand the converter's operation. The prototype design considered enhanced power handling capabilities using the paralleling method. The power switches are controlled by a digital circuit based on the RP2040 microcontroller, which generates PWM signals with a fixed duty cycle at 100 kHz. The average material cost of the converter was significantly minimized to approximately $15. Experimental tests showed an efficiency of 93.5% and an average temperature of 31°C, making it a promising solution for sustainable agriculture in resource-constrained environments.Keywords— Smallholder farms, Low-cost, SEPIC converter, Solar water pump, PLECS

Abstract: Titanium and its alloys are the 5th most common metallic materials used world wide but the markets volume of titanium materials, is difficult to expand due to associated production costs, and the decrease of those costs are critical in order to expand their markets. A possible option is the alloy design, i.e. using low price alloying element, such as iron, chromium, manganese and oxygen, and the selection of other raw materials, i.e. grade of sponge titanium. In beta titanium alloy, Ti-Mo system alloy using ferro-molybdeum was developed by USA company or Ti-Cr-Fe-Al beta alloy were also developed by Japan company. In this paper, those developed alloys were explained. Furthermore, substitution of Ti-10V-2Fe-3Al near beta alloy, presenters are studying about Ti-Mn-Fe-Al alloy.

Abstract: The building sector plays a significant role in reducing global energy use and carbon emissions. In the European Union (EU), the building stock represents 40% of total energy use and in which cooling and heating systems represent over 50%. Portugal is one of the EU countries where the consequences of energy poverty are most evident due to the families' financial inability to adequately climate their homes. The reasons are several, but they are mainly linked to buildings' poor passive thermal performance, resulting from inadequate adaptation to the climatic context and reduced thermal insulation. Thus, it is necessary to develop solutions to increase buildings’ thermal performance and reduce their potential environmental impact, which arises mainly from the significant use of active systems. In this sense, natural building materials are a promising solution, reducing energy use and carbon emissions related to buildings. This research studies the potential use of reed found in Portugal (Arundo donax) as a thermal insulation material. Its physical characterisation and the influence of geometry configuration on its thermal performance are evaluated. Its durability was studied too. Reed stalks were used to carry out the physical and durability tests. A reed board (150 x 150 mm) was built, and its thermal performance was tested in a hotbox. According to the results, the characteristics of reeds found in Portugal make it suitable to be used as a building material. Furthermore, regardless of the configuration studied, the reeds have a satisfactory thermal performance to be used as thermal insulation, under the requirements defined by Portuguese thermal regulation, Re ≥ 0.30 (m².oC)/W. There is a trend to the mould growth in the reed, but only under favourable conditions. Additionally, considering the abundance of reed throughout the Portuguese territory, this is an eco-friendly and low-cost option that gathers all requirements to be more used in the construction market.

Abstract: Organophosphorous pesticide (OP), one of the most commonly used pesticides, could have serious adverse effects on human health and the environment. As the maximum residue limit (MRL) of OPs in food and water is low, it is in great demand to develop integrated, portable, user-friendly devices for the rapid and sensitive detection of OP residue. This work aims to present a homemade handhold device and screen printing electrode (SPE) chip for rapid, sensitive, and one-step detection of OPs. A handhold device was designed and fabricated to connect with smartphone to readout the electrochemical signals. Taking advantage of a three-electrode sensor chip and the inhibiting reaction of acetylcholine esterase (AchE), Trichlorphon can be detected in a considerable low detection limit of 1 ng/mL. By using the as-fabricated device and chip, the detection time was only 5 min and each test costs less than $1. The platform will allow point-of-care testing (POCT) of OPs and other targets, which shows promise for healthy and environmental monitoring.

Abstract: Glass fiber reinforced gypsum panels (GFRG) are hollow panels made from modified gypsum plaster and reinforced with chopped glass fibers. The hollow cores inside the walls can be filled with in-situ concrete/reinforced concrete or insulation material to increase the structural strength or the thermal insulation, respectively. GFRG panels can be unfilled when used as partition walls, but when used as load bearing walls, it is filled with M20 grade concrete (reinforced concrete filling) in order to resist the gravity and lateral loads. The study was conducted in two stages: First stage involves formulation of an alternate light weight mix to be used in the GFRG panels in lieu of M20 grade concrete by partial replacement of cement with phosphogypsum and fine aggregate with shredded thermocol and thereby conducting experimental investigations to obtain the optimum combination. In the second stage the above formulated mix is filled in GFRG panels and experimental investigations are conducted to evaluate the strength parameters and the results are compared with the panels filled with conventional M20 concrete mix. The results of the first stage of experimental investigations are presented in this paper.

Abstract: This research focuses on the development of low cost powder metallurgy (PM) Ti alloys suitable for application in PM thermomechanical processing with mechanical properties comparable to those of wrought Ti6Al4V alloy. The alloy systems studied are Ti3Al2V, Ti5Fe and Ti3.2Fe1Cr0.6Ni0.1Mo (Ti5SS). The alloy mixtures were produced by blending Ti HDH powders with Al40V, 316SS master alloy powders or elemental Fe powder. The blended powders were further consolidated using various methods: high vacuum sintering (HVS), induction sintering (IS), powder compact forging (PCF) and powder compact extrusion (PCE). It is found that, PM Ti3Al2V and Ti5Fe alloy processed by PCE or PCF followed by recrystallization annealing (RA) achieved tensile properties comparable with wrought Ti6Al4V alloy. Tensile properties such as yield strength (YS) of 910MPa, UTS of 1010MPa and 15% elongation to fracture for Ti3Al2V alloy are reported. Ti5Fe alloy gives YS and UTS of 870MPa and 968MPa respectively, combined with 20.3% elongation to fracture. The tensile results are related to the microstructure developed during the consolidation processes. The oxygen contamination as a result of the high temperature processing is also reported.

Abstract: There are situations like collapsed buildings or inaccessible indoor spaces for humans, when ground robots may be of the most value. Small robots will likely to get into voids and go deeper than the 18-20 feet that a camera on a probe or a borescope can go into. The ground robots would be used to try to understand the internal layout of the structure and to avoid a secondary collapse, for example. In this paper are presented some results on the attempt to create a low cost mapping and guiding system suitable for small robots based on low cost LIDAR (LIght Detection And Ranging) devices. The aim was to create the mapping and guiding system minimizing the costs and maximizing the performances and capabilities.

Abstract: Tetrabutylammonium acetate, a new solvent, can dissolve cellulose (8 wt%) within 5 min at 40°C with dimethyl sulfoxide as coslovent without any pretreatment or inert gas atmosphere. The dissolution detail was recorded by Confocal Laser Scanning Microscope. And the viscosity of cellulose solution prepared from the new solvent was only 10% of that prepared from [BMIM]Cl. Moreover, the influence of molecular weight on the rheology of the cellulose solution was investigated. With the increase of the molecular weight, the viscosity was increasing and the cross-over point of the storage modulus (G′) and loss modulus (G′′) curves shifted to the lower angular frequency. The structure and mechanical properties of the fibers prepared from the cellulose solution were characterized by FT-IR, XRD, SEM and DSC. During the dissolution process, the crystalline region of the cellulose was destroyed and the celluloseIbecame amorphous. However, part of amorphous cellulose transformed into celluloseII by the wet spinning, indicated by FT-IR and XRD spectrum. SEM images showed that the resulting fibers were homogeneous with smooth surfaces and circular cross-sections. Meanwhile, the cellulose fibers had good thermal stability, measured by DSC. This work provided a promising way to prepare cellulose fibers with good physical properties, which was green, low cost and suitable for industrial production.

Abstract: A dedicated or specialized friction stir welding (FSW) machine is quite costly especially for pipe joining. Therefore, not many institutions manage to conduct their research on FSW at their facilities. Besides that, the difficulty to design a jig that can hold the complex shape such as pipe section tightly and easily to be removed during and after the FSW process respectively will nullify the intentions. In many institutions, there was either conventional or CNC milling machine available in their workshops. Thus, a jig called orbital clamping unit (OCU) was designed to suit this milling machine. It acts as an additional device to enable this milling machine to run as FSW machine at a lower cost, hence fully utilized the available facility in the workshop. Several good samples were successfully produced by using this jig and milling machine