Continuum robot has attracted extensive attention since its emergence.It has multi-degree of freedom and high compliance,which give it significant advantages when traveling and operating in narrow spaces.The flexural ...Continuum robot has attracted extensive attention since its emergence.It has multi-degree of freedom and high compliance,which give it significant advantages when traveling and operating in narrow spaces.The flexural virtual-center of motion(VCM)mechanism can be machined integrally,and this way eliminates the assembly between joints.Thus,it is well suited for use as a continuum robot joint.Therefore,a design method for continuum robots based on the VCM mechanism is proposed in this study.First,a novel VCM mechanism is formed using a double leaf-type isosceles-trapezoidal flexural pivot(D-LITFP),which is composed of a series of superimposed LITFPs,to enlarge its stroke.Then,the pseudo-rigid body(PRB)model of the leaf is extended to the VCM mechanism,and the stiffness and stroke of the D-LITFP are modeled.Second,the VCM mechanism is combined to form a flexural joint suitable for the continuum robot.Finally,experiments and simulations are used to validate the accuracy and validity of the PRB model by analyzing the performance(stiffness and stroke)of the VCM mechanism.Furthermore,the motion performance of the designed continuum robot is evaluated.Results show that the maximum stroke of the VCM mechanism is approximately 14.2°,the axial compressive strength is approximately 1915 N/mm,and the repeatable positioning accuracies of the continuum robot is approximately±1.47°(bending angle)and±2.46°(bending direction).展开更多
基金supported in part by the National Natural Science Foundation of China(Grant No.U1813221)the National Key R&D Program of China(Grant No.2019YFB1311200).
文摘Continuum robot has attracted extensive attention since its emergence.It has multi-degree of freedom and high compliance,which give it significant advantages when traveling and operating in narrow spaces.The flexural virtual-center of motion(VCM)mechanism can be machined integrally,and this way eliminates the assembly between joints.Thus,it is well suited for use as a continuum robot joint.Therefore,a design method for continuum robots based on the VCM mechanism is proposed in this study.First,a novel VCM mechanism is formed using a double leaf-type isosceles-trapezoidal flexural pivot(D-LITFP),which is composed of a series of superimposed LITFPs,to enlarge its stroke.Then,the pseudo-rigid body(PRB)model of the leaf is extended to the VCM mechanism,and the stiffness and stroke of the D-LITFP are modeled.Second,the VCM mechanism is combined to form a flexural joint suitable for the continuum robot.Finally,experiments and simulations are used to validate the accuracy and validity of the PRB model by analyzing the performance(stiffness and stroke)of the VCM mechanism.Furthermore,the motion performance of the designed continuum robot is evaluated.Results show that the maximum stroke of the VCM mechanism is approximately 14.2°,the axial compressive strength is approximately 1915 N/mm,and the repeatable positioning accuracies of the continuum robot is approximately±1.47°(bending angle)and±2.46°(bending direction).
