A completely new approach for the fabrication of 3-axis thermal accelerometers is presented in this paper. Micromolded polystyrene micro-parts are assembled with polyimide membranes enabling the construction of thermal accelerometers. The use of polymers (polystyrene and polyimide) with low thermal conductivities improves the overall power consumption of the thermal accelerometer and enables a simple and low-cost fabrication process (no clean room infrastructure required). The accelerometer is composed of 4 polystyrene microinjected structural micro- parts (two identical top parts and two identical central parts) and three polyimide membranes (two identical z-axis membranes and a central membrane). The microinjected parts provide the mechanical support for the active elements that are placed on the membranes (the heater and the temperature sensors). Coupled 3D thermo-electric-fluidic FEM simulations show that current design has a sensitivity of 1.6°C/g in the X-Y directions and 0.2°C/g in the Z direction for a central heater temperature of 300°C

Polycaprolactone (PCL) scaffolds were produced by electrospinning. Polymeric solutions in a mix of dichloromethane (DCM) and dimethylformamide were electrospun to form fibers in the sub-micron range. Physical properties of the PCL solutions were characterized with respect to density, viscosity, conductivity and surface tension. Processing was optimized following Taguchi's methodology to select the set of processing parameters that resulted in producing fibers with the smallest diameters, minimum number of defects and with the narrowest distribution of fiber diameter. Morphology of electrospun fibers was qualitatively and quantitatively analyzed for the different sets of processing parameters. The optimum conditions found to electrospun PCL were used to process PCL solutions containing nanoparticles of hydroxyapatite (HA) or bioactive glass (BG). Bioactivity of nanocomposite electrospun membranes in simulated body fluid (SBF) was analyzed and biological response was tested by assessing proliferation and viability of MT3C3-E1 preosteoblasts cultured on PCL and its nanocomposite membranes.

Electronic devices are sensitive to electromagnetic (EM) emissions, and require electromagnetic shielding protection to ensure good operation, and prevent noise, malfunctioning, or even burning. To ensure protection, it is important to develop suitable material and design solutions for electronic enclosures. Most common enclosures are made with metal alloys using traditional manufacturing methods. However, using thermoplastic composites combined with additive manufacturing (AM) technologies emerges as an alternative that enables the fabrication of complex parts that are lightweight, consolidated, and oxidation- and corrosion-resistant. In this research, an AM technique based on material extrusion was used to print 2 mm-thick specimens with a multi-material made of micro-carbon fiber (CF)-filled polyamide that was reinforced at specific layers using continuous carbon fibers stacked with a 90° rotation to each other. The specimens’ electromagnetic shielding effectiveness (EMSE) was evaluated in the frequency band of 0.03–3 GHz using the coaxial transmission line method. Depending on the number of CF layers, the EM shielding obtained can be up to 70 dB, with a specific shielding up to 60 dB.cm³/g, predominantly by the absorption mechanism, being 22 times higher than without the CF layers. These findings promote this innovative approach to lightweight customizable solutions for EM shielding applications.

The concept, fabrication process, and characterization of a three-axis thermal accelerometer are presented in this paper. A combination of microelectromechanical systems (MEMS) technology with microinjection molding enables the realization of functional, highly complex 3D geometries at the microscale, used here for the fabrication of a fully integrated three-axis accelerometer. While conventional thermal accelerometers are silicon based, using MEMS technologies only, the integration of polymeric materials and technologies into the fabrication process can greatly improve the realization of three-axis devices while diminishing the typical thermal losses. Three-axis thermal accelerometers were successfully fabricated by combining the proposed technologies proving the viability of the concept. Fabricated accelerometers show xy -axis sensitivity around 8 mV g ⁻¹ , a z -axis sensitivity of 2.2 mV g ⁻¹ for a power of 45 mW and a 4 Hz bandwidth (bandwidth is based on simulations). Thermal tests performed showed that the heater can sustain up to 280 °C without overheating the remaining structures and damaging the device.

A novel 3 dimensional model using a coupled fluidic-solid-interaction (FSI) approach is used to simulate the response of a 3-axis thermal accelerometer. The model is fully parametric, enables static and dynamic analysis and includes thermal dependent properties on both solid and fluidic domains. Unlike previous modeling approaches found in literature, the proposed model can be used to determine the power required for sensor operation, bandwidth and quality factor, and, due to the three dimensional approach, it is possible to use the total temperature variation along the temperature sensors (previous 2D models only give temperature differences in a single point) to simulate a more real sensor response. The model was applied to a polymer based 3-axis thermal accelerometer and simulation results using the proposed model show a power consumption of 23 mW and a sensitivity of 1mV/g and 368μV/g in the XY and Z directions respectively

Electrostatic discharge-sensitive devices (ESDS) consist of electronic systems that are easily damaged by electrostatic fields or discharges. To safely stow and transit the ESDS, Bosch Car Multimedia S.A. resorts to thermoformed trays with a specific design for each product configuration. Although efficient, the solutions’ specificity arose logistic issues that created the need for an alternative approach. This paper reports the investigation for the development of a flexible tray, based on an electrostatic-dissipative integral skin foam. First, a commercial integral skin polyurethane foam was evaluated by varying components mixing ratio. Once achieved a suitable combination of hardness and density, post-formulation additives (colour and anti-static) were investigated. Free expansion foaming stages were assessed and cured foams were characterised in terms of electrostatic discharge protection. Moulded foams with variable patterns were developed and evaluated considering the application purpose requirements. Real-scale prototypes of the most adequate concept design were produced and analysed.