Enlarging regions of stable running with segmented legs

— In human and animal running spring-like leg behavior is found, and similar concepts have been demonstrated by various robotic systems in the past. In general, a spring-mass model provides self-stabilizing characteristics against external perturbations originated in leg-ground interactions and motor control. Although most of these systems made use of linear spring-like legs. The question addressed in this paper is the influence of leg segmentation (i.e. the use of rotational joint and two limb-segments) to the self-stability of running, as it appears to be a common design principle in nature. This paper shows that, with the leg segmentation, the system is able to perform self-stable running behavior in significantly broader ranges of running speed and control parameters (e.g. control of angle of attack at touchdown, and adjustment of spring stiffness) by exploiting a nonlinear relationship between leg force and leg compression. The concept is investigated by using a twosegment leg...

• Type: Conference
• Year: 2008
• Where: ICRA
• Authors: Juergen Rummel, Fumiya Iida, James Andrew Smith, André Seyfarth
• Keywords: ICRA 2008, Leg Segmentation, Robotics, Spring-like Leg Behavior, Spring-like Legs