Split-Belt Adaptation Model
of a Decerebrate Cat Using
a Quadruped Robot with Learning
Kodai Kodono
(B) and Hiroshi Kimura
Kyoto Institute of Technology, Sakyo-ku Matssugasaki, Kyoto 606-8585, Japan
m9623107@edu.kit.ac.jp, kimura61@kit.ac.jp
http://www.robotlocomotion.kit.ac.jp/kotetsu/
Abstract. We propose a model connecting body dynamics and sensor
feedback to investigate gait adaptation mechanisms of decerebrate cats
in split-belt waking. In our previous studies, we proposed a leg controller
using leg loading/unloading for the leg phase transition of a quadruped
robot: “Kotetsu.” The purpose of this study is to make a model of splitbelt gait adaptation in spinal cats and decerebrate cats to refer to biological knowledge and to evaluate the validity of those models using Kotetsu.
We construct the spinal cat model integrating our leg controller with
Frigon’s spinal cord model. Also, we employ motor learning in the cerebellum by long-term depression for the decerebrate cat model. As the
results of experiments, we show that early adaptation in the split-belt
walking is obtained by the stance-to-swing leg phase transition mechanism in the spinal cat model. We also show that late adaptation in
split-belt walking is obtained by motor learning as the step distance
adjustment in the decerebrate cat model. The validity of those models
is evaluated by comparing durations of forelegs bi-support phases and
duty ratios in the transition from tied-belt to split-belt walking between
decerebrate cats and Kotetsu with the decerebrate cat model.
Keywords: Split-belt walk · Decerebrate cat model · Quadruped
robot
1 Introduction
1.1 Walking of a Decerebrate Cat on a Split-Belt Treadmill
Animals and humans change the gait and adapt to perturbations while walking.
In spite of such evidence, detailed mechanisms of such gait adaptation have
not yet been clarified. To investigate such adaptation mechanisms, experiments
to make animals [1–4] and humans walk on split-belt
1 treadmills were much
1 The situation of different belt speed in left and right is named split-belt; that of the
same belt speed is named tied-belt. A leg on the fast belt or the slow belt is named
fast-leg or slow-leg (normal-leg), respectively.
c
Springer Nature Switzerland AG 2020
V. Vouloutsi et al. (Eds.): Living Machines 2020, LNAI 12413, pp. 217–229, 2020.
https://doi.org/10.1007/978-3-030-64313-3_21
of a Decerebrate Cat Using
a Quadruped Robot with Learning
Kodai Kodono
(B) and Hiroshi Kimura
Kyoto Institute of Technology, Sakyo-ku Matssugasaki, Kyoto 606-8585, Japan
m9623107@edu.kit.ac.jp, kimura61@kit.ac.jp
http://www.robotlocomotion.kit.ac.jp/kotetsu/
Abstract. We propose a model connecting body dynamics and sensor
feedback to investigate gait adaptation mechanisms of decerebrate cats
in split-belt waking. In our previous studies, we proposed a leg controller
using leg loading/unloading for the leg phase transition of a quadruped
robot: “Kotetsu.” The purpose of this study is to make a model of splitbelt gait adaptation in spinal cats and decerebrate cats to refer to biological knowledge and to evaluate the validity of those models using Kotetsu.
We construct the spinal cat model integrating our leg controller with
Frigon’s spinal cord model. Also, we employ motor learning in the cerebellum by long-term depression for the decerebrate cat model. As the
results of experiments, we show that early adaptation in the split-belt
walking is obtained by the stance-to-swing leg phase transition mechanism in the spinal cat model. We also show that late adaptation in
split-belt walking is obtained by motor learning as the step distance
adjustment in the decerebrate cat model. The validity of those models
is evaluated by comparing durations of forelegs bi-support phases and
duty ratios in the transition from tied-belt to split-belt walking between
decerebrate cats and Kotetsu with the decerebrate cat model.
Keywords: Split-belt walk · Decerebrate cat model · Quadruped
robot
1 Introduction
1.1 Walking of a Decerebrate Cat on a Split-Belt Treadmill
Animals and humans change the gait and adapt to perturbations while walking.
In spite of such evidence, detailed mechanisms of such gait adaptation have
not yet been clarified. To investigate such adaptation mechanisms, experiments
to make animals [1–4] and humans walk on split-belt
1 treadmills were much
1 The situation of different belt speed in left and right is named split-belt; that of the
same belt speed is named tied-belt. A leg on the fast belt or the slow belt is named
fast-leg or slow-leg (normal-leg), respectively.
c
Springer Nature Switzerland AG 2020
V. Vouloutsi et al. (Eds.): Living Machines 2020, LNAI 12413, pp. 217–229, 2020.
https://doi.org/10.1007/978-3-030-64313-3_21