scholarly journals Influence of Arm Joint Limitation on Interlimb Coordination during Split-belt Treadmill Walking

2019 ◽  
Vol 8 (0) ◽  
pp. 130-136 ◽  
Author(s):  
Keisuke Hirata ◽  
Hiroki Hanawa ◽  
Taku Miyazawa ◽  
Takanori Kokubun ◽  
Keisuke Kubota ◽  
...  
2015 ◽  
Vol 12 (110) ◽  
pp. 20150542 ◽  
Author(s):  
Soichiro Fujiki ◽  
Shinya Aoi ◽  
Tetsuro Funato ◽  
Nozomi Tomita ◽  
Kei Senda ◽  
...  

Human walking behaviour adaptation strategies have previously been examined using split-belt treadmills, which have two parallel independently controlled belts. In such human split-belt treadmill walking, two types of adaptations have been identified: early and late. Early-type adaptations appear as rapid changes in interlimb and intralimb coordination activities when the belt speeds of the treadmill change between tied (same speed for both belts) and split-belt (different speeds for each belt) configurations. By contrast, late-type adaptations occur after the early-type adaptations as a gradual change and only involve interlimb coordination. Furthermore, interlimb coordination shows after-effects that are related to these adaptations. It has been suggested that these adaptations are governed primarily by the spinal cord and cerebellum, but the underlying mechanism remains unclear. Because various physiological findings suggest that foot contact timing is crucial to adaptive locomotion, this paper reports on the development of a two-layered control model for walking composed of spinal and cerebellar models, and on its use as the focus of our control model. The spinal model generates rhythmic motor commands using an oscillator network based on a central pattern generator and modulates the commands formulated in immediate response to foot contact, while the cerebellar model modifies motor commands through learning based on error information related to differences between the predicted and actual foot contact timings of each leg. We investigated adaptive behaviour and its mechanism by split-belt treadmill walking experiments using both computer simulations and an experimental bipedal robot. Our results showed that the robot exhibited rapid changes in interlimb and intralimb coordination that were similar to the early-type adaptations observed in humans. In addition, despite the lack of direct interlimb coordination control, gradual changes and after-effects in the interlimb coordination appeared in a manner that was similar to the late-type adaptations and after-effects observed in humans. The adaptation results of the robot were then evaluated in comparison with human split-belt treadmill walking, and the adaptation mechanism was clarified from a dynamic viewpoint.


2021 ◽  
Vol 8 ◽  
Author(s):  
Shinya Aoi ◽  
Takashi Amano ◽  
Soichiro Fujiki ◽  
Kei Senda ◽  
Kazuo Tsuchiya

Interlimb coordination plays an important role in adaptive locomotion of humans and animals. This has been investigated using a split-belt treadmill, which imposes different speeds on the two sides of the body. Two types of adaptation have been identified, namely fast and slow adaptations. Fast adaptation induces asymmetric interlimb coordination soon after a change of the treadmill speed condition from same speed for both belts to different speeds. In contrast, slow adaptation slowly reduces the asymmetry after fast adaptation. It has been suggested that these adaptations are primarily achieved by the spinal reflex and cerebellar learning. However, these adaptation mechanisms remain unclear due to the complicated dynamics of locomotion. In our previous work, we developed a locomotion control system for a biped robot based on the spinal reflex and cerebellar learning. We reproduced the fast and slow adaptations observed in humans during split-belt treadmill walking of the biped robot and clarified the adaptation mechanisms from a dynamic viewpoint by focusing on the changes in the relative positions between the center of mass and foot stance induced by reflex and learning. In this study, we modified the control system for application to a quadruped robot. We demonstrate that even though the basic gait pattern of our robot is different from that of general quadrupeds (due to limitations of the robot experiment), fast and slow adaptations that are similar to those of quadrupeds appear during split-belt treadmill walking of the quadruped robot. Furthermore, we clarify these adaptation mechanisms from a dynamic viewpoint, as done in our previous work. These results will increase the understanding of how fast and slow adaptations are generated in quadrupedal locomotion on a split-belt treadmill through body dynamics and sensorimotor integration via the spinal reflex and cerebellar learning and help the development of control strategies for adaptive locomotion of quadruped robots.


2020 ◽  
Vol 9 (4) ◽  
pp. 571-584
Author(s):  
Anne E. Cox ◽  
Sarah Ullrich-French ◽  
Elaine A. Hargreaves ◽  
Amanda K. McMahon

1972 ◽  
Vol 70 (1) ◽  
pp. 73-80 ◽  
Author(s):  
L. W. Raymond ◽  
J. Sode ◽  
J. R. Tucci

ABSTRACT Treadmill walking produced a prompt reduction in serum cortisol in 10 of 12 healthy military men. In contrast, two subjects, with pre-exercise tachycardia and apprehension, showed an increase in serum cortisol with treadmill exercise. In each group, the changes produced by exercise were still evident 30 and 60 minutes after the 30-minute treadmill walk. Urine collected before and after exercise contained similar amounts of 11-hydroxy- and 17-hydroxycorticosteroid material. These results may be explained by an increase in cortisol utilization during exercise and/or by a change in its distribution. The data indicate that in the absence of psychic factors, non-exhaustive exercise is not associated with pituitary adrenocortical activation.


Author(s):  
Yann Combret ◽  
Clément Medrinal ◽  
Guillaume Prieur ◽  
Aurora Robledo Quesada ◽  
Timothée Gillot ◽  
...  

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