Kabushiki Kaisha Toyota Chuo Kenkyusho

Toyota Motor Engineering & Manufacturing North America, Inc.

Atsushi Kawamoto

Yoshihiro Iwano

Tsuyoshi Nomura

Hiroshi Osada

Hiroshi Hohjo

Masanori Usui

Yuka Yamada

Takayuki Aoyama

Nobuyuki Mori

Mizuho Inagaki

Tadayoshi Matsumori

Tsuguo Kondoh

Kimihiko Yasuda

Hidehiko Kimura

A method for optimizing orientations of an anisotropic material in a component. For example, the method overcomes the non-uniqueness and gimbal locking problems associated with using Euler angles to define the orientation by instead parameterizing the orientation using an orientation tensor that is a self-dyadic product of a direction vector. To avoid non-linear constraints in the mathematical design variables used in the optimization, isoparametric shape functions map the mathematical design variables to physical design variables, and the mapping ensures that various constraints associated with tensor invariants of the orientation tensor are satisfied even though these constraints are not directly imposed on the mathematical design variables. The physical design variables are used to model the component, whereas optimization is performed using the mathematical design variables. Thus, optimization is greatly simplified by removing the tensor-invariant constraints from the optimization step to the mapping step.

Orientation optimization in components fabricated with anisotropic material properties

A thermal conductive stress relaxation structure is interposed between a high-temperature substance and a low-temperature substance to conduct heat in a heat-transfer direction from the high-temperature substance to the low-temperature substance. The structure includes an assembly configured such that a thermal conductive material gathers in a non-bonded state having stress relaxation effect. Such an assembly is a rolled-up body configured such that a carbon-based sheet material and a metal-based sheet material are alternately rolled up, for example. This structure has one or more interfaces at which adjacent parts can slide, thereby dividing a deformable region to relax the thermal stress. It has a low rigidity and can thus deform to release the thermal stress. The structure can suppress the thermal stresses and the shape changes that would be generated in the high-temperature substance and the low-temperature substance, and each physical body located there between.

Thermal conductive stress relaxation structure

Local observer frame LOC which is located near a body and moving on a global coordinate system is used for locally observing the body together with the global coordinate system. The rigid body displacement and elastic vibration of the body are represented by rigid body modes and elastic modes respectively, and analyzed by modal analysis uniformly handling these rigid body modes and elastic modes.

Body displacement and vibration analysis method

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Nagakute, Japan

Atsushi Kawamoto