Proposal of an Actively Controllable Landing Leg for Lunar-Planetary Lander

For touchdown mission on rough but interesting terrain where no space probe has gone before, like "crater central hill" and edge of lunar lava tube hole, an actively controllable landing system is required. This paper proposes an of actively controlled landing leg system by using a variable coefficient damper. Further, to show the effectiveness of the actively controlled landing leg system, we simulate touchdown based on mathematical models. Further, show the effectiveness of the actively controlled landing leg system based on the proposed controller. Simulation model is virtually-fixed in two-dimensional plane, and investigates robustness of lander to touchdown to slope terrain and the case where the lander has initial horizontal velocity and initial attitude angle error.