Development of Landing Rebound Reduction Mechanism Utilizing Magnetic Damper for Multicopters

Abstract

This paper proposes a rebound reduction mechanism for landing multicopter. Multicopter applications in the logistics industry are expected to increase owing to the aging of logistics drivers and the decline in their numbers. Currently, most multicopters land on their designated landing pads. However, these pads are not always available at the destination, and landing on rough terrain is needed in such cases. This paper describes the development of a mechanism to reduce rebound during landing, which can easily cause tipping over. The mechanism should be lightweight to ensure that battery power is conserved and that payload transport capability is increased. Simultaneously, the mechanism should be robust against environmental variations because multicopters are used outdoors and under various temperature conditions. A mechanism consisting of a spring and a magnetic damper is proposed and is modeled using multibody dynamics. It is known that the magnetic damper possesses robustness against temperature variations. Moreover, this paper presents the design parameter optimization for the proposed mechanism considering both the rebound reduction effect and weight reduction. The spring constant and viscous damping coefficient of the proposed mechanism are determined via numerical simulations with the electromagnetic simulator JMAG. The effectiveness of the proposed mechanism is verified via vertical freefall simulations. A simple experimental system is used to evaluate the mechanism, and the experimental results indicate that the mechanism is effective.