analysis and design of a dynamic-based control algorithm for running a five-linked bipedal runner robot

In this study, we designed a time-invariant controller for the dynamic stabilization of a five-link runner robot in two dimensions. The running is modeled with three phases of single-stance phase, flight phase, and collision phase. The dynamic equations of the robot in each phase were extracted by the Lagrange method. The robot's heel-strike is also rigidly modeled. The controller in each phase guides the robot by zeroing predetermined outputs in the form of path trajectories via the feedback linearization method. The outputs are designed so that a rhythmic running will be presented by the robot on a limit cycle. The created limit cycle has been determined and its stability has been investigated using the Poincare return map. The robot's controller robustness to disturbances has been investigated and shown that the controller can return the robot to a limit cycle with a deviation of 20% with respect to the stable limit cycle. It has been shown that the relevant geometry by the proposed controller can absorb the gait into the limit cycle in conditions of deviation of 20% in 10 steps.