Inverse kinematics of a humanoid robot with non-spherical hip: a hybrid algorithm approach

摘要

This paper describes an approach to solve theudinverse kinematics problem of humanoid robots whoseudconstruction shows a small but non negligible offset atudthe hip which prevents any purely analytical solution toudbe developed. Knowing that a purely numerical solutionudis not feasible due to variable efficiency problems, theudproposed one first neglects the offset presence in order to obtain an approximate “solution” by means of anudanalytical algorithm based on screw theory, and then usesudit as the initial condition of a numerical refiningudprocedure based on the Levenberg‐Marquardt algorithm.udIn this way, few iterations are needed for any specifiedudattitude, making it possible to implement the algorithmudfor real‐time applications. As a way to show theudalgorithm’s implementation, one case of study isudconsidered throughout the paper, represented by theudSILO2 humanoid robot.