Design and locomotivity analysis of a novel deformable two-wheel-like mobile mechanism

Abstract

Purpose The purpose of this paper is to propose a deformable two-wheel-like mobile mechanism based on overconstrained mechanism, with the abilities of fast rolling and obstacle surmounting. The drive torque of the multi-mode motions is generated by self-deformation. Moreover, the analyses of feasibility and locomotivity of two mobile modes are presented. Design/methodology/approach The main body of the two-wheel-like mobile mechanism is a kind of centrally driven 4 R linkages. The mobile mechanism can achieve the capabilities of fast rolling and obstacle surmounting through integrating two mobile modes (spherical-like rolling mode and polyhedral-like obstacle-surmounting mode) and can switch to the corresponding mode to move or surmount obstacles. The mobility and kinematics of the mobile modes are analyzed. Findings Based on the results of kinematics analysis and dynamics analysis of the wheel-like mechanism, the spherical-like rolling mode has the capability of fast rolling, and the polyhedral-like obstacle-surmounting mode has the capability of surmounting different obstacle heights by two submodes (quasi-static obstacle-surmounting submode and dynamic obstacle-surmounting submode). The proposed concept is verified by experiments on a physical prototype. Originality/value The work presented in this paper is a novel exploration to apply bar linkages in the field of scout. The two-wheel-like mobile mechanism improves the torque imbalance of bar linkages by centrally driven method, removes the rear support structures of the traditional two-wheeled mechanisms by self-deformation and increases the height of obstacle surmounting by mode switching angle.