Configuration design and kinematic performance analysis of a parallel wheelset suspension for a multi-wheeled pressurized lunar rover

Abstract

When a multi-wheeled pressurized lunar rover (MWPLR) travels over rough terrain, the ability of its suspension to maintain wheel–ground contact is critical for achieving heavy load distribution and increasing its payload capacity. If the MWPLR uses an independent suspension, increasing the number of wheels worsens the wheel-off-ground problem. If the MWPLR utilizes a rocker–bogie suspension with a planar open-loop kinematic chain, it will have difficulty withstanding lateral impacts. In this study, to solve the above problems, the configurations of the 4-SS parallel mechanism were enumerated based on the Grassmann line geometry and screw theory to design a two-degree-of-freedom parallel wheelset suspension. The suspension integrated two axially parallel wheels on the same moving platform. Kinematic analysis showed that no singularities occurred in the workspace. The moving platform enabled large vertical movement and rotation of ±30°. Simulations showed that the suspension dramatically improved the ride comfort and wheel–ground contact capability of the MWPLR.