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Self-sufficient self-oscillating microsystem driven by low power at low Reynolds numbers.

ABSTRACT: Oscillations at several hertz are a key feature of dynamic behavior of various biological entities, such as the pulsating heart, firing neurons, or the sperm-beating flagellum. Inspired by nature’s fundamental self-oscillations, we use electroactive polymer microactuators and three-dimensional microswitches to create a synthetic electromechanical parametric relaxation oscillator (EMPRO) that relies on the shape change of micropatterned polypyrrole and generates a rhythmic motion at biologically relevant stroke frequencies of up to ~95 Hz. We incorporate an Ag-Mg electrochemical battery into the EMPRO for autonomous operation in a nontoxic environment. Such a self-sufficient self-oscillating microsystem offers new opportunities for artificial life at low Reynolds numbers by, for instance, mimicking and replacing nature’s propulsion and pumping units.

SUBMITTER: Akbar F

PROVIDER: S-EPMC8550224 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Self-sufficient self-oscillating microsystem driven by low power at low Reynolds numbers.

Akbar Farzin F Rivkin Boris B Aziz Azaam A Becker Christian C Karnaushenko Dmitriy D DD Medina-Sánchez Mariana M Karnaushenko Daniil D Schmidt Oliver G OG

Science advances 20211027 44

Oscillations at several hertz are a key feature of dynamic behavior of various biological entities, such as the pulsating heart, firing neurons, or the sperm-beating flagellum. Inspired by nature’s fundamental self-oscillations, we use electroactive polymer microactuators and three-dimensional microswitches to create a synthetic electromechanical parametric relaxation oscillator (EMPRO) that relies on the shape change of micropatterned polypyrrole and generates a rhythmic motion at biologically ...[more]

PMID: 34705511

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