Research On Spatial Single-loop Biped Linkage Mechanisms

This thesis presents the idea of using the spatial single-loop mechanism as the whole mechanical body of the biped robot. A systematic research on spatial single-loop four-link and six-link biped mechanisms which contain the R and C joints is carried out. It includes theoretical research, simulation research, experimental research and applied research of one typical case.Firstly, an untraditional application of the four-link RCCR mechanism is revealed. It is used as a novel biped walking mechanism. By taking advantage of the singular configuration of the mechanism, two actuators are employed to realize planar movements. Mobility analysis, walking mode planning, kinematic analysis, gait planning and stability analysis are performed respectively, and a prototype is developed and tested.Secondly, through the horizontal extension of the biped RCCR mechanism, a deeper research is carried out and other configurations can be gained by all means, including conventional mechanism synthesis method, repetitious trial, inspiration and intuition. These biped four-link mechanisms form a family with a common feature that they all consist of two revolute and two cylindric joints. Three main categories, including eight configurations are put forward. The singular configuration is cleverly used rather than avoided to perform the walking and turning. Their structure descriptions and walking simulations are accomplished. Afterwards, the mobility, kinematic and stability analyses are studied, the design considerations are discussed, and footworkspace analyses are carried out. Finally, four prototypes are developed to preliminary verify the feasibility of these proposed concepts.Thirdly, through the vertical extension of the biped RCCR mechanism, two novel spatial single-loop six-link mechanisms are proposed. They are spatial single-loop six-link RRCRCR and RRCCRR mechanism. Moreover, these mechanisms are used to be biped walking mechanisms, and the main research includes:(1) The proposed spatial six-link RRCCRR biped mechanism can move along a line or a curve by three walking modes that are dwell adjustment mode, limit position adjustment mode and any position adjustment mode. Mobility, kinematic, gait planning and stability analyses are performed respectively, and a prototype is developed. Lastly, a potential application is considered and two manipulating modes (sphere manipulating mode and cylinder manipulating mode) are analyzed.(2) The proposed spatial six-link RRCCRR biped mechanism can reach any position on the ground by a crawling mode and a somersaulting mode alternatively. After the robot reach a designate position, it can work in manipulation mode. Mobility, walking mode, kinematic and stability analyses are performed respectively. Based on this biped RRCCRR mechanisms, a biped3T lifter can be used in industry is designed and analyzed. Finally, the proposed concept is verified by experiments on a prototype. The work is one of new explorations to apply traditional spatial linkage mechanisms to the field of biped robot, and is also a new attempt to use the biped robot, that is seldom used used in the industrial field, as a mobile manipulator robot platform with3T manipulator ability.Finally, a summary is given and a prospect is brought forward. A kind of spatial single-loop six-link Schatz6R mobile mechanism including Schatz6R crawling and biped Schatz6R sliding mechanisms is proposed. Some modular mobile mechanisms based on the Schatz6R crawling mechanism are achieved. And the potential application prospect of the spatial single-loop mobile linkage mechanism is presented.