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The utilization of lattice structure in engineering components by additive manufacturing (AM) is gaining attention due to its lightweight design, high strength-to-weight ratio, and effective material utilization. Producing holes in additively manufactured lattice structures with dimensional accuracy is challenging. In the current study, we fabricate near circular through-holes on deterministic lattice structured components fabricated by laser powder bed fusion by utilizing electric discharge machining (EDM). In the additively manufactured Inconel 718 (IN718) lattice structure, nodes are connected by strut leaving voids/pores amongst different nodal points. Due to EDM, the nodes at the boundary of the hole experience concentration plasma interaction, heating, and rapid cooling, which causes a substantial change in the microstructure. The selective removal of material from different nodal positions causes uncharacteristic recast layers, partial damages, and uncontrolled cracking of the struts. In the present study, we investigated and characterized the differential behaviour and mechanism of various surface integrity issues associated with the selective material removal of LPBF IN718 lattice structures and their elements (nodes and struts). [ABSTRACT FROM AUTHOR]

There has been a continuous downfall in equipping the Primary Health Centres (PHCs) with infrastructure, facilities, and workforce to provide basic minimum primary healthcare services to the underserved population in the Indian context. The main goal of this research is to look at the infrastructure and manpower in a sample of PHCs in the Kanpur district of Uttar Pradesh, India. The interview template exclusively for Product-Service System (PSS) by Singapore University of Technology and Design-Massachusetts Institute of Technology (SUTD-MIT) was used to study randomly selected samples of 51 PHCs. The data were examined using the Indian Public Health Standards (IPHS) of the Indian government. Some of the key findings included the lack of workforce and their commitment, shortage of space, electricity, and water supply. To find a solution for the found lacunae, this article also discusses about the functioning of Mobile Hospitals (MHs) depending upon the contexts and thus extracting lessons for a new intervention in the primary health care system delivery model. Finally, a new healthcare delivery model in the form of a mobile Primary Health Centre (mPHC) is proposed based on the field study and the synthesis of historical literature on MH. [ABSTRACT FROM AUTHOR]

Wheelchair (WC) design elements are subjected to the accessibility and assistive needs of a person with locomotor disability. In order to pursue a holistic design for a stairclimbing WC, there is a need for literature review on WC functions reported for both stair climbing and plane surface movement. A total of 112 Research articles are reviewed for the purpose of extracting the relationship between WC design elements and the functions associated with them. Stairclimbing technologies are reviewed for their technological assessment in terms of functional elements associated with stairclimbing. Cross-functional mapping between functional elements and their dominant function is performed. Heat map for primary user needs and associated design elements is generated from cross mapping. A design gap for user's functional needs is indicated from the review of literature on prototypes and products of WC. The literature in stairclimbing technology is primarily focussed on stair climbing capability and not on the other functional needs, such as safety, ride comfort, seat comfort, manoeuvrability, etc. For attaining the goal of an effective rehabilitation, it is important to design and develop an assistive technology that can provide maximum accessibility and functioning for a person with disability. In case of locomotor disability, wheelchair (WC) is the most empowering tool that can assist people in both accessibility and activities of daily living. This review of literature was conducted to draw out the functions fulfilled by a WC, such as safety, comfort, propulsion for its users and the associated WC elements like seat, wheels, backrest, etc., that are required to fulfil those functions. WC being the most important technological intervention in the life of a person who cannot walk should be designed with the highest level of empathy. Therefore, each and every aspect of the user's physical and emotional needs should be catered up to the limits of engineering design. The research on stair climbing technologies has also grown exponentially, fuelled by technological growth in engineering mechanisms, ambient awareness sensors, actuators, etc. The review attempts to envelop such technologies and consolidate them on the basis of their capabilities and efficacies. The virtue of stair climbing has been realized through some novel and innovative mechanisms reviewed in this article that can be integrated with the research in field of functional elements required to carry out primary functions of a disabled person, such as safety, comfort, intuitiveness, etc. This review can help in coupling both of them in a more rational way where a designer who is designing the technology is more empathetic towards the design for accessibility. It can also help user in becoming more confident towards adapting a new assistive technology. [ABSTRACT FROM AUTHOR]

In the current work, numerical simulation and experimentation are carried out to investigate the performance of powder mixed dielectric in the electrical discharge micromachining process. Three distinct powders, namely aluminum (electrically conductive), silicon (semi-conductive), and aluminum oxide/alumina (electrically non-conductive) dispersed in the kerosene dielectric, are considered. For a constant applied voltage, a silicon powder particle inserted in the gap immersed with liquid dielectric shows an enlargement in the inter-electrode gap (∼38% and 63% with circular and elliptical powder) compared to the pure dielectric. The enlarged inter-electrode gap increases the machining yield due to improved flushing efficiency. The intensification of the electric field near the particles' surface lowers the breakdown voltage and charging time of the capacitor for the constant inter-electrode gap, resulting in a decrease in discharge energy per pulse and increased spark frequency. The influence of powder material properties and their sizes on breakdown strength is analyzed. Further, the discharge parameters acquired from the electric field numerical simulation of powder mixed dielectric have been utilized to conduct the numerical simulation of single crater formation with pure dielectric and powder mixed dielectric. The simulated single carters' dimensions are validated with the experimentally machined single craters. Numerical simulation and experimentation of powder mixed dielectric depict the effectiveness of aluminum oxide powders in addition to silicon and aluminum powders when dispersed in kerosene host dielectric. [ABSTRACT FROM AUTHOR]