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This paper presents a case study of the design, fabrication, and evaluation of an automotive rear-frame model made of variable axial composites (VAC), using a tailored fiber placement (TFP) technique. Conventionally, the design of a three-dimensional complex VAC structure places significant demands on mechanical engineering expertise (for anisotropic structural design) and on man-hours (for fiber-path CAD). The proposed methods facilitate the design of complex VAC structures with significantly reduced manpower requirements. A computational design method, anisotropic topology optimization, was used to create the base design. The fiber paths on the preform surfaces were generated using a Turing pattern algorithm (based on optimized fiber orientation distributions) subsequent to designing developable three-dimensional surfaces to fill the interior of the target structure. The preforms were fabricated using a computer numerical control (CNC) embroidery machine by stitching the raw fiber tow onto the base fabric in accordance with the generated fiber path data. After stacking the preforms in the mold, they were formed using vacuum-assisted resin-transfer molding (VaRTM). The static stiffness of the prototype was evaluated experimentally, and the results were compared with numerical simulations. This study demonstrates the potential for achieving further weight reduction in large-scale 3D structures by combining innovative computational design techniques with advanced fabrication methods.

Organic conductors consisting of donor and anion molecules provide various important study fields such as superconductivity and electron correlation. π electrons are responsible for the emergence of these phenomena. On the other hand, the coexistent systems of π electrons and localized 3d spins have been realized by introducing magnetic anions. Such coexistent systems are called π-d systems. In π-d systems, various fascinating magnetic and conducting phenomena are observed due to the coupling of π electrons and localized 3d electrons (π-d interaction). One of the most striking phenomena is magnetic field-induced superconductivity, which is first observed in λ-(BETS)2FeCl4, where BETS is bis(ethylenedithio)tetraselenafulvalene. On the other hand, λ-(BETS)2FeCl4 shows a metal-insulator transition accompanying an antiferromagnetic ordering at TN of 8.3K and the unconventional antiferromagnetic state that 3d spins behave as if they stay paramagnetic even below TN. These phenomena are also considered to be caused by the π-d interaction, but their mechanisms have not been demonstrated. Recently, a new λ-type π-d system of λ-(BEDT-STF)2FeCl4, where BEDT-STF is bis(ethylenedithio)dithiadiselenafulvalene, has been developed. In this review, the influence of bandwidth control by donor substitution and the dilution effect of magnetic ions on the magnetic properties of the π-d system will be discussed. We will demonstrate that site-selective magnetization measurements by 13CNMR and 57Fe Mössbauer measurements and heat capacity measurements provide important information to understand the mechanism of unconventional magnetic properties in π-d systems. We would also like to introduce the advantages of the 13CNMR measurements using one-sided-13C-enriched donor molecules, which are the key technique in our experiments. [ABSTRACT FROM AUTHOR]

Locomotive soft robots (SoRos) have gained prominence due to their adaptability. Traditional locomotive SoRo design is based on limb structures inspired by biological organisms and requires human intervention. Evolutionary robotics, designed using evolutionary algorithms (EAs), have shown potential for automatic design. However, EA-based methods face the challenge of high computational cost when considering multiphysics in locomotion, including materials, actuations, and interactions with environments. Here, we present a design approach for pneumatic SoRos that integrates gradient-based topology optimization with multiphysics material point method (MPM) simulations. This approach starts with a simple initial shape (a cube with a central cavity). The topology optimization with MPM then automatically and iteratively designs the SoRo shape. We design two SoRos, one for walking and one for climbing. These SoRos are 3D printed and exhibit the same locomotion features as in the simulations. This study presents an efficient strategy for designing SoRos, demonstrating that a purely mathematical process can produce limb-like structures seen in biological organisms. [ABSTRACT FROM AUTHOR]