Autonomous energy transducer: proposition, example, basic characteristics

We propose a concept of autonomous energy transducer at a molecular scale, where output is produced with small input energy, not very much larger than the thermal energy, without restriction of magnitude or timing of input, and without any control after the input. As an example that satisfies these requisites, a dynamical systems model with several degrees of freedom is proposed, which transduces input energy to output motion on the average. It is shown that this transduction is robust and the coupling between input and output is generally loose. How this transducer works is analyzed in terms of dynamical systems theory, where chaotic dynamics of the internal degrees of freedom, as well as duration of excited conformation of an active part which is self-organized with the energy flow, is essential. We also discuss possible relationships to enzyme dynamics or protein motors.