Kinematical and dynamic analysis of biped robots' locomotion using dynamic object manipulation approach

In this paper, we try to interpret "Duality of Dynamic Locomotion and Dynamic Object Manipulation". Since our main goal in this paper is to offer the duality concept and to validate it with a case study, we deal with the problem in a simple and abstract system. As a case study, we describe the duality between the problem of 2D dynamic object manipulation of a sphere using two planar manipulators and 2D dynamic locomotion of lower part of a biped robot. Having obtained the equations of dynamic object manipulation, we change the boundary conditions of the problem in such a way that both radius and mass of sphere object tend to infinity. Simultaneously, both of size and mass of manipulators' base, i.e. the planet earth, tend to some values in the order of human body's mass and dimension. Regarding these changes, we can change the dynamic object manipulation problem to a dynamic locomotion one. A simple control strategy is introduced to handle the impact problem between the manipulators (legs) and the object (the earth). In addition, a motion planning system is devised in such a way that the manipulators (legs) catch and throw the manipulated object (the earth) in appropriate configurations. Simulation results are given to support the developed idea.