ナチュラルダイナミクスを使用した二足歩行ロボットの力学と制御

電気通信大学200

Construction of Gait Adaptation Model in Human Splitbelt Treadmill Walking

There are a huge number of studies that measure kinematics, dynamics, the oxygen uptake and so on in human walking on the treadmill. Especially in walking on the splitbelt treadmill where the speed of the right and left belt is different, remarkable differences in kinematics are seen between normal and cerebellar disease subjects. In order to construct the gait adaptation model of such human splitbelt treadmill walking, we proposed a simple control model and made a newly developed 2D biped robot walk on the splitbelt treadmill. We combined the conventional limit-cycle based control consisting of joint PD-control, cyclic motion trajectory planning and a stepping reflex with a newly proposed adjustment of P-gain at the hip joint of the stance leg. We showed that the data of robot (normal subject model and cerebellum disease subject model) experiments had high similarities with the data of normal subjects and cerebellum disease subjects experiments carried out by Reisman et al. (2005) and Morton and Bastian (2006) in ratios and patterns. We also showed that P-gain at the hip joint of the stance leg was the control parameter of adaptation for symmetric gaits in splitbelt walking and P-gain adjustment corresponded to muscle stiffness adjustment by the cerebellum. Consequently, we successfully proposed the gait adaptation model in human splitbelt treadmill walking and confirmed the validity of our hypotheses and the proposed model using the biped robot

二脚ロボットを用いた人のSplit-Belt Treadmill歩容適応モデルの提案

Recently, there have been several trials that use robotics as a tool forneuroscience, especially in locomotion studies. In the case of bipedallocomotion, human walking has been investigated extensively over severaldecades.A number of studies have measured kinematics, dynamics, and oxygenuptake while a person walks on a treadmill. In particular, during walking ona split-belt treadmill, in which the left and right belts have different speeds,remarkable differences in kinematics are observed between normal subjectsand subjects with cerebellar disease.In order to understand mechanisms behind such phenomena, it is useful toconstruct the control model of human walking, simulate it using amusculoskeletal model and compare the simulation results with the resultsof human experiments. But since it is difficult to simulate friction, collisionwith ground, effects of elastic materials and so on, we would like to carry outexperiments using a real machine (robot) rather than computer simulations.In order to construct a gait adaptation model of such human split-belttreadmill walking, we proposed a simple control model and developed a new2D biped robot walk on a split-belt treadmill. We combined the conventionallimit-cycle based control consisting of joint PD-control, cyclic motiontrajectory planning, and a stepping reflex with a newly proposed adjustmentof P-gain at the hip joint of the stance leg.The data obtained in experiments on robot (normal subject model andcerebellum disease subject model) have highly similar ratios and patterns todata obtained in experiments on normal subjects and subjects withcerebellar disease carried out by Bastian et al. We also showed that theP-gain at the hip joint of the stance leg was the control parameter ofadaptation for symmetric gaits in split-belt walking and that P-gainadjustment corresponded to muscle stiffness adjustment by the cerebellum.Consequently, we successfully proposed a gait adaptation model for humanSplit-belt treadmill walking and confirmed the validity of our hypothesesand the proposed model using the biped robot.電気通信大学200