A theoretical study on fundamental of vehicle behavior under force control

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H. Sakai


Drivers move steering wheel by controlling both angle and torque of steering wheel. The steering manner that drivers steer only by torque is called “force control.” Since a dynamics of steering system is added to vehicle planar motion under force control, natural frequencies under force control differ from yaw natural frequency. To improve vehicle dynamic behavior, hence, not only yaw natural frequency, but also natural frequencies under force control are important. Therefore this paper aims to obtain symbolic natural frequencies under force control. Firstly, this paper obtains a characteristic equation under force control, which is expressed as a quartic equation of Laplace operator s. Secondly, Laplace operator s is replaced another variable to transform the quartic equation into a biquadratic equation. Solving the biquadratic equation, this paper obtains symbolic formulas of the frequencies. Considering these formulas, this paper proposes an improvement method of vehicle behavior under force control.

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How to Cite
Sakai, H. (2018). A theoretical study on fundamental of vehicle behavior under force control. Journal of Research and Applications in Mechanical Engineering, 4(1), 35–45. Retrieved from https://ph01.tci-thaijo.org/index.php/jrame/article/view/138791


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