Research On Ground Mobile Mechanism Based On Single-loop 6R Spatial Linkage

The research object of this paper is a single-loop 6R mobile mechanism.Based on the method of configuration synthesis of single-loop kinematic chains,various principles of single-loop 6R linkages have been proposed.The single-loop 6R linkgae with different constraints has been selected to do theoretical research and analysis.The mobile mechanism based on the principle linkage has been analysed,including gait planning,simulationanalysisandexperimentalverification.(1)Taking the constraint force and couple into the consideration,a series of principle linkages have been proposed based on the Type Synthesis of Single-Loop Kinematic Chains.The axes position of revolute joints and various configUrations of single-loop 6R linkages can be obtained with different constraints based on screw theory.Typical overconstrained 6R mechanisms are summarized and classified into synthesis results.(2)The linkage with one constraint couple is selected as the research object.The kinematics,degrees of freedom and singularity are studied and analyzed based on homogeneous transformation matrix,SVD decomposition and screw theory.According to the kinematics of the linkage,the single-mode mobile 6R mechanism has been proposed.The mobile mechanism only has a kind of peristaltic movement mode,and its mobility,folding and obstacles characteristics are analyzed in Adams simulation.A prototype model is made to verify the correctness of the proposed concept.(3)The linakge with two constraint force is selected as the research object.The kinematics,degree of freedom and singularity of the mechanism are studied and analyzed.According to kinematics relation,singularity position and freedom degree analysis,the dual-mode mobile 6R mechanism has been proposed,which has two kinds of moving modes,including peristaltic movement and steering modes.Its mobility,folding and obstacles eharacteristics are analyzed in Adams simulation.Make a prototype model to verify the correctness of the proposed concept.(4)A linkage with a constraint force and couple is selected as the research object,and its kinematics,degree of freedom and singular position are studied and simulated.The three-mode mobile 6R mechanism has been proposed,which has has three kinds of moving modes,including peristaltic movement and two kinds of steering mode.The mobility,folding and obstacles characteristics are analyzed.A prototype model is made to verify the correctness of the proposed concept.(5)Two mechanisms with multiple constraint forces and couples are selected as the research object.Kinematics,degree of freedom and moving gait of the mechanism are studied and simulated.The mobile mechanisms have multiple moving modes and analyze their movement.The mobility,folding and obstacles characteristics are analyzed.Compare all the proposed mobile mechanisms and analyze their advantages and disadvantages.