a group of us researchers has produced a robotic set of legs which they believe is the first to 1 model walking in a biologically accurate manner. the 2 architecture, musculoskeletal architecture and 3 feedback pathways in humans have been simplified and built into the robot, giving it a 4 human-like walking gait that can be viewed in this video -- http://www.youtube.com/watch?v=mnd7lqisbhm&feature=youtu.be.
the biological accuracy of this robot, which has been presented july 6, in iop publishing's journal of neural engineering, has allowed the researchers to investigate the processes 5 walking in humans and may 6（支持） theories of how babies learn to walk, as well as 7 to understand how 8-cord-injury patients can recover the ability to walk.
a key 9 of the human walking system is the central pattern 10 (cpg). the cpg is a neural network in the lumbar region（腰部） of the spinal cord that generates 11 muscle signals. the cpg produces, and then controls, these signals by 12 information from different parts of the body that are responding to the environment. this is what allows people to walk without needing to think about it.
the simplest form of a cpg is a half-centre, which consists of just two neurons that fire signals alternatively, producing a rhythm. the robot contains an artificial half-centre as well as 13 that deliver information back to the half-centre, including load sensors that sense force in the limb when the leg is pressed against a stepping surface.
co-author of the study, dr theresa klein, said: "interestingly, we were able to produce a walking gait, without balance, which 14 human walking with only a simple half-centre controlling the 15 and a set of reflex responses controlling the lower limb."
the researchers, from the university of arizona, hypothesize that babies start off with a simple half-centre, similar to the one developed in this robot, and over time they 'learn' a network for a more complex walking pattern. this could explain why babies have been seen to exhibit a simple walking pattern when placed on a 16 even before they have learnt to walk -- a simple half-centre is already in place.
"this underlying network may also form the core of the cpg and may explain how people with spinal cord injuries can 17 walking ability if properly 18 in the months after the injury," dr klein continued.
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