A method is presented for embedding sensors into the lining of sports helmets purpose monitoring head impact in contact sports. Additive manufacturing was used to embed optical fiber-based pressure inside thermoplastic polyurethane (TPU), a material and shock-dampening that fills space between helmet's hard outer shell head. proof-of-concept has successfully demonstrated sensitive shock-monitor...

This paper analyzes the effect of thin and thick walls on functional properties 3D printed cell structures, designed from open structures inspired by natural world. Different types unit cells with same density are introduced. The studied in morphology mechanical performance, particular effective density, compressive stiffness, energy absorption under cyclic loading. Material extrusion process t...

The objective of the study is to analyze thermomechanical response a two-dimensional monodisperse granular system made thermoplastic polyurethane (TPU) cylinders with elliptical cross-section. Cyclic confined compression tests were performed while an infrared (IR) camera measured temperature changes at surface cylinders. Thermoelastic coupling and mechanical dissipation distinguished in thermal...

Shape memory behavior of crystalline shape memory polyurethane (SPU) reinforced with graphene, which utilizes melting temperature as a shape recovery temperature, was examined with various external actuating stimuli such as direct heating, resistive heating, and infrared (IR) heating. Compatibility of graphene with crystalline SPU was adjusted by altering the structure of the hard segment of th...

This study reports the preparation and characterization of composites with recycled poly(vinyl butyral) (PVB) and residue of rigid polyurethane foam (PUr), with PUr contents of 20, 35 and 50 wt %, using an extruder equipped with a Maillefer single screw and injection molding. The components of the composites were thermally characterized using differential scanning calorimetry (DSC) and thermogr...

A soft lithographic method is described for casting functional thermoplastic devices with microscale features without the need for specialized tools or equipment. In the thermoplastic soft lithography process, termed solvent casting, low temperature supersaturated solutions of thermoplastic are poured over solvent permeable PDMS molds which allow omnidirectional solvent removal as they template...

Purpose Most support surfaces in comfort applications and sporting equipment are made from pressure-relieving foam such as viscoelastic polyurethane. However, for some users, is not the best material it acts a thermal insulator may offer adequate postural support. The additive manufacturing of alleviate these issues, but design investigation needed to optimize printing parameters use pressure r...