Discover new developments at the frontiers of optical micro/nanofiber (MNF) and its remarkable attributes for use in tactile sensors and soft actuators. Learn how this ideal mix of the potentialities in fiber optics and micro/nanotechnology is redefining human-computer interplay, medical tracking, and micro-robotics.
Optical Micro-Microfibers or Nanofibers Revealed
Optical micro-nanofibers (MNF) belong to this new class of waveguide structure which has gained popularity in only a few years. Together, these characteristics lead to optical properties in the MNFs that are very different from those of standard fibers.
Such properties include low transmission loss, high light field confinement, large evanescent field, a tight bending radius and its lightweight structure. Importantly, MNFs are also compatible with standard fiber; capable of serving as both a complement or an independent technology.
The unique properties of MNFs have enabled the realization of high performance flexible optoelectronic devices in terms of sensitivity, compactness, and energy efficiency. This has been especially validated by the developments in tactile sensors and soft actuators wherein MNFs are now being widely utilized as drivers for state-of-the-art solutions.
Making ‘Optical Skin’ Into a Reality With Tactile Sensors
One of the most promising implementations of MNF technology is in building flexible tactile sensors, also known as “optical skin”. The unique properties of sensors permit to measure a large set of physical magnitudes: pressure, temperature, hardness, pulse, respiration with high sensitivity, very fast time response and an amazing electromagnetic resilience.
The manufacture of MNF tactile sensors is a delicate process including fiber drawing, polymer packaging, device fabrication and system designCompleteListenerini_successful_bulk_device_integration_STAGE 2_biohazard [–> full] These sensors are then further classified according to the different structural designs, including taper type (single-cone), double-cone type, resonator type, grating type, interferometer type, and micro-coupler-type.
By use of wavelength demodulation, or intensity demodulation technical sensing signals can be extracted with different configurations of sensors. In this context, wavelength demodulation is the technique observed for WGM resonators—for FP resonators—the movement of resonant wavelengths as—well as Theta resonators– Sagnac Reson large hole fibers and Fiber Bragg Gratings. In contrast, for intensity detection -an easier type of measurement-, tiny semiconductor light sources together with photodiodes to monitor the change in MNF transmittance would allow building more compact and efficient sensing systems.
This has resulted in the development of innovative applications using MNF tactile sensors, including data gloves, intelligent wristbands, smart textiles presenting integrated proximity and tactile composite multi-parameter interactive interfaces. Both technologies are lightweight, ultra-sensitive, low-power and highly robust against electromagnetic interference for human-computer interaction (HCI), medical monitoring and more.
Conclusion
The recent development in the field of optical micro-nanofiber (MNF) technology have opened a new era for tactile sensors and soft actuators. These flexible devices with high performance will have promising applications in fields of human-computer interaction, medical monitoring, micro-robotics. Utilizing the exceptional characteristics of magnetostrictive nanofiber composites, they have crafted flexible, responsive and energy saving technologies for opening up new horizons in tactile sensing and actuation. With this technology only becoming more refined, we can safely assume new and spectacular applications will arise from it to morph the way our worlds both digital and physical are experienced.
