Theories of bipedal walking: an odyssey

Abstract

In this paper six theories of bipedal walking, and the evidence in support of the theories, are reviewed. They include: evolution, minimising energy consumption, maturation in children, central pattern generators, linking control and effect, and robots on two legs. Specifically, the six theories posit that: (1) bipedalism is the fundamental evolutionary adaptation that sets hominids-and therefore humans-apart from other primates; (2) locomotion is the translation of the centre of gravity along a pathway requiring the least expenditure of energy; (3) when a young child takes its first few halting steps, his or her biomechanical strategy is to minimise the risk of falling; (4) a dedicated network of interneurons in the spinal cord generates the rhythm and cyclic pattern of electromyographic signals that give rise to bipedal gait; (5) bipedal locomotion is generated through global entrainment of the neural system on the one hand, and the musculoskeletal system plus environment on the other; and (6) powered dynamic gait in a bipedal robot can be realised only through a strategy which is based on stability and real-time feedback control. The published record suggests that each of the theories has some measure of support. However, it is important to note that there are other important theories of locomotion which have not been covered in this review. Despite such omissions, this odyssey has explored the wide spectrum of bipedal walking, from its origins through to the integration of the nervous, muscular and skeletal systems. r

Recovery of locomotion after injury inDrosophiladepends on proprioception

“…Of course, the behavioral details of movement vary wildly even in the case of a specific modality such as legged locomotion, as seen in bipeds (Vaughan, 2003), quadrupeds (Alexander, 1984), various hexapods (Cruse, 1976;Full and Tu, 1991;Grabowska et al, 2012;Mendes et al, 2013;Couzin-Fuchs et al, 2015) and octopods (Blichkan and Full, 1987). Even when the number of limbs is held constant, the pattern of limb placement during locomotion (gait) can vary greatly within and between species, as reviewed in Holmes et al (2006) and Borgmann and Büschges (2015).…”

Development of pendulum mechanism and kinematic coordination from the first unsupported steps in toddlers

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In addition, in the on-line version, the first sentence of the second paragraph of the subsection 'Relation with speed' in the Results (p. 3805) should read: Fig.·5A shows the R vs Fr function for our toddlers at the first unsupported steps, 1-5·months later, for children older than 2·years of age, and for adults.The print version of the article is correct.We apologise to authors and readers for any inconvenience these errors may have caused.

3797Spatiotemporal dynamics of normal walking in human adults is governed by general principles, including mechanisms of propulsion, stability, kinematic coordination and mechanical energy exchange (Alexander, 1989;Capaday, 2002;Dietz, 2002;Lacquaniti et al, 1999;Poppele and Bosco, 2003;Saibene and Minetti, 2003;Vaughan, 2003;Winter, 1991). One basic mechanism of walking is represented by the inverted pendulum model in which the centre of mass (COM) of the body vaults over the stance leg in an arc (Cavagna et al, 1963(Cavagna et al, , 1976.

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Bio-inspired vertebral column, compliance and semi-passive dynamics in a lightweight humanoid robot

“…Many researchers were interested in biomechanics of human walking (see e.g [31]). These studies describe accurately the kinematics and dynamics of legs during walking (see [37]). …”

“…Let us note that the active use of the pelvis, independently of the torso for the step is largely inspired by the human walk (see e.g. [37], [30]). …”