title: Kinematic and Gait Similarities between Crawling Human Infants and Other Quadruped Mammals.
abstract: Crawling on hands and knees is an early pattern of human infant locomotion, which offers an interesting way of studying quadrupedalism in one of its simplest form. We investigate how crawling human infants compare to other quadruped mammals, especially primates. We present quantitative data on both the gait and kinematics of seven 10-month-old crawling infants. Body movements were measured with an optoelectronic system giving precise data on 3-dimensional limb movements. Crawling on hands and knees is very similar to the locomotion of non-human primates in terms of the quite protracted arm at touch-down, the coordination between the spine movements in the lateral plane and the limbs, the relatively extended limbs during locomotion and the strong correlation between stance duration and speed of locomotion. However, there are important differences compared to primates, such as the choice of a lateral-sequence walking gait, which is similar to most non-primate mammals and the relatively stiff elbows during stance as opposed to the quite compliant gaits of primates. These finding raise the question of the role of both the mechanical structure of the body and neural control on the determination of these characteristics.
authors.affiliation: Autonomous Motion Department, Max-Planck Institute for Intelligent Systems , Tübingen , Germany.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Righetti
authors.affiliation: Uppsala Child and Baby Lab, Department of Psychology, Uppsala University , Uppsala , Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Nylén
authors.affiliation: Uppsala Child and Baby Lab, Department of Psychology, Uppsala University , Uppsala , Sweden.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Rosander
authors.affiliation: Biorobotics Laboratory, Interfaculty Institute of Bioengineering, School of Engineering, École Polytechnique Fédérale de Lausanne , Lausanne , Switzerland.
authors.forename: Auke Jan
authors.initials: AJ
authors.lastname: Ijspeert
keywords: crawling; gait; infant locomotion; kinematics; quadruped locomotion