To solve the flexible sensing measurement problem of flexural bending of soft pneumatic drivers
a method of curvature measurement and shape reconstruction by embedding fiber grating into a strain limiting layer for a soft pneumatic driver was proposed. First
the relationship between the spectral characteristics of the fiber grating and bending curvature of the strain limiting layer were theoretically analyzed. Then
a device that performs soft sensing
demodulation
and curvature calibration based on the spectral characteristics of fiber grating was developed. The characteristics of the reflection spectrum of fiber grating under different curvatures were experimentally analyzed
and the curve of the center wavelength shift and change in curvature of the fiber grating were calculated. Finally
the curvature values of a soft pneumatic driver under different bending states were calculated
and the deformation shape of the soft pneumatic driver was reconstructed. Results show that the curvature measurement and shape sensing of the soft pneumatic driver can be realized by changing the reflection spectrum of fiber grating embedded in the strain limiting layer. The maximum error between the measured values of the fiber grating sensing and soft pneumatic driver curvature is 2.1%. This fiber sensing method represents a promising application for soft sensing and closed-loop control of soft pneumatic drivers.
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references
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