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The double-V micro-structures (DVMS) are a type of auxetic materials showing the negative Poisson’s ratio which can contract under compression different from the conventional materials. Due to the unique properties, it can have higher stiffness and better impact resistance with lightweight. In this paper, a cylindrical honeycomb tube based on the double-V unit cell is proposed. Firstly, the nominal Poisson’s ration and Young’s modulus in the longitudinal and circumferential directions are derived analytically. The effect of the geometry parameters of the DVMS tube on the mechanical properties is studied thoroughly. Also, the effect of the width in the radial direction on these mechanical properties is analyzed. Secondly, the finite element (FE) method is utilized to obtain the numerical solutions and verify the accuracy of the analytical solutions. The results show that there is a good agreement between the results obtained by the two methods when the width is smaller enough.

Connected and automated vehicles (CAVs) are gaining momentum, especially in the potential to improve road safety and reducing energy consumption and emissions. Lane-change maneuver is one of the most important conventional parts of automated driving. We address the problem of optimally CAVs to accomplish an automated lane-change and eliminate potential collision during the lane-change process on a curved road. Drivers’ safety, comfort, convenience, and fuel economy are also engaged in trajectory planning. We assume that the centripetal motion displacement and the rotational angular displacement meet the requirement of odd-order polynomial constrains. Then, the polynomial coefficient of the trajectory can be reduced and the mathematical model of virtual trajectory for lane-change can be designed based on the models of centripetal displacement and angular displacement by applying the above constrains and boundary conditions.