The use of magnetic field treatment (MFT) was investigated to establish the appropriate temperature needed to enhance the out‐of‐plane effective thermal conductivity (k) of polyimide (PI)‐based composite sheets. Hexagonal boron nitride (hBN) surfaces were decorated with magnetite particles (Fe3O4@hBN) for use as fillers. The magnetite amount was adjusted to a Fe3O4/hBN weight ratio of 0.2 in most cases. When MFT was carried out at the temperature starting from 80, 90, and 100°C, the effective k was enhanced compared with the lack of MFT. On the other hand, the effective k was not enhanced by the use of MFT at the starting temperature of either 150 or 200°C. Moreover, the cross‐sectional scanning electron microscope images and X‐ray diffractometer analyses of the sheets prepared both with and without MFT were consistent with the results of the effective k measurements. Namely, the fillers inside the sheets moved and rotated under MFT at the starting temperature of 80, 90, and 100°C. On the other hand, for MFT starting from either 150 or 200°C, the fillers were restrained due to high viscosity of the composite solutions. The results of measurements of the breakdown voltages also implied the formation of filler paths inside the sheets.

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A working six-legged robot which can switch three modes of locomotion and manipulation by using some legs as arms is under development: six-leg mode and two kinds of four-leg two-arm modes, where the robot holds and manipulates an object with two arms. Attaching hands to the legs enables five-leg one-arm mode; the robot grasps a small object with one hand and manipulates the object with one arm, while walking stably with five legs. Because the arm has three DOF, the robot needs to move its body with the five legs in order to control the pose of the hand. The present paper proposes a coordinated control method of five legs and one arm to manipulate five-DOF pose of the hand. The robot stands on the five legs. From the desired velocity and angular velocity of the hand, the joint velocities of the arm and the velocity and angular velocity of the body are determined. From the determined body velocity and angular velocity, the joint velocities of the five legs are obtained. These joint velocities are commanded to the robot. If at least one of the five support legs reaches the limit of its movable area, the robot stops the arm and body temporarily. Then the five legs step to the center of their movable areas. After the five legs finish stepping, the robot resumes the control of the hand. Experiments of moving the hand along straight lines show the validity of the proposed method.