EXPLORING THE LOMBARD PARADOXON IN A BIPEDAL MUSCULOSKELETAL ROBOT

Towards advanced bipedal locomotion musculoskeletal system design has received much attention in recent years. It has been recognized that designing and developing new actuators with the properties of the human muscle-tendon complex is only one of the many tasks that have to be fulfilled in order to come close to the powerful human musculoskeletal system enabling the human to such versatile dynamic movements that no robot has been capable of replicating yet. But equally important is a technical implementation of the key characteristics of the human musculoskeletal leg system, segmentation and elastic leg behavior enabled by the mono-and biarticular muscles. So far, there has been an overwhelming consensus in biomechanics literature regarding the joint movements caused by biarticular muscles. In reality, however, they are responsible for an additional action during the second half of ground contact during fast dynamic motions in humans that has not yet been addressed by bipedal robot locomotion studies. Using BioBiped1, a bipedal compliant robot with human-inspired mono-and biarticular tendons, we demonstrate by means of a detailed multibody system dynamics simulation how this positive effect subserve energy-efficient dynamic 1D hopping motions and enables us to establish a novel bipedal locomotion model.