A biologically based neural system coordinates the joints and legs of a tetrapod.
A biologically inspired neural control system has been developed that coordinates a tetrapod trotting gait in the sagittal plane. The developed neuromechanical system is used to explore properties of connections in inter-leg and intra-leg coordination. The neural controller is built with biologically based neurons and synapses, and connections are based on data from literature where available. It is applied to a planar biomechanical model of a rat with 14 joints, each actuated by a pair of antagonistic Hill muscle models. The controller generates tension in the muscles through activation of simulated motoneurons. The hind leg and inter-leg control networks are based on pathways discovered in cat research tuned to the kinematic motions of a rat. The foreleg network was developed by extrapolating analogous pathways from the hind legs. The formulated intra-leg and inter-leg networks properly coordinate the joints and produce motions similar to those of a walking rat. Changing the strength of a single inter-leg connection is sufficient to account for differences in phase timing in different trotting rats.
Case Western Reserve University, Cleveland OH 44106, USA.
Alexander
A
Hunt
Manuela
M
Schmidt
Martin
M
Fischer
Roger
R
Quinn
D000818:Animals; D001683:Biological Clocks / Q000502:physiology; D032701:Biomimetics / Q000379:methods*; D003198:Computer Simulation; D025461:Feedback, Physiological / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006614:Hindlimb / Q000294:innervation / Q000502:physiology*; D007596:Joints / Q000294:innervation / Q000502:physiology; D008959:Models, Neurological; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D016571:Neural Networks, Computer; D004856:Postural Balance / Q000502:physiology; D051381:Rats; D012371:Robotics / Q000379:methods