Hideo Yuasa

Energy-based pattern transition in quadrupedal locomotion with oscillator and mechanical model

The anatomical researches on nerve systems have elucidated that the central pattern generator (CPG) in spinal cord concerns the generation of locomotion pattern. The biomechanics, on the other hands, tells us that the energy expenditure is one of the crucial factors for the pattern selection. Thus it is possible that the energy evaluation has some effects on the CPG. This paper propose the CPG and mechanical model of quadrupeds; the CPG model plans the pattern of locomotion and the mechanical model is used to calculate the energy consumption. The simulation shows the pattern transition based on the energy evaluation.

An autonomous decentralized recognition system having a dispersive wave property

The concept of an autonomous decentralized system can be applied to recognizing various complicated and skillful actions performed by humans. This concept is the basis for a proposed pattern recognition system, which can be regarded as an associative memory system modeled by a reaction-diffusion equation system. This paper improves upon this pattern recognition system using the property of a dispersive wave instead of diffusion. This improvement has three advantages: acceleration of recognition, spread of similar regions and human-like hysteresis in recognition. Computer simulation has shown that propagation of a dispersive wave is faster than that of diffusion, and that the dispersive wave system exhibits the above advantageous properties of recognition.

Autonomous decentralized system with self-organizing function and its application to generation of locomotive patterns

The authors consider a synthesis approach to autonomous decentralized systems in which the functional order of the entire system is generated by cooperative interaction among its subsystems, each of which has the autonomy to control a part of the state of the system, and its application to pattern generators of animal locomotion. Biological locomotive rhythms, their generators, and gait patterns of quadrupeds are reviewed briefly. A design principle for autonomous coordination of many oscillators is proposed. Using these results, a gait pattern generator that suitably changes gait patterns for its moving speed is synthesized. It is shown, using computer simulations, that the system generates and changes patterns suitable for its moving speed, i.e., walk, trot, and gallop.<<ETX>>