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Customization is an important issue for assistive gloves because it affects glove performance. In this letter, we propose an assembly based customizable soft pneumatic assistive glove, named Exo-Glove PM. Pneumatic soft robots generally consist of a single structure with embedded actuators. However, when assembled, the region where the assemblies are connected easily undergoes large stress concentration that leads to failure. To overcome this issue, we have developed a hybrid actuator module that combines a soft actuation structure and rigid joining methods. In general, rigid joining methods require a bulky design to enable easy assembly, but Exo-Glove PM is designed to create pathways for assembly tools to access the bolt heads by bending certain parts. This novel way of joining assemblies allows soft robots to be built of multiple parts while minimizing the volume. It ensures small module size and enables modules to cover a wide range of hand sizes; the distance between each module is matched to the length of the user's phalanges using spacers. This approach allows users to customize the glove by assembly of standardized modules and maximizes the comfort and the performance of the glove without custom manufacturing and, thus, reduces costs.

We propose a new capacitive microinclinometer where oblique comb electrodes and double-folded suspension springs are aligned parallel to the vertical (111) plane of (110) silicon. The oblique comb utilizes both the overlapped area and the gap between movable and stationary electrodes, resulting in a considerable increase in sensitivity (capacitance change/angle). The resolution becomes even higher by taking advantage of the smooth (111) sidewalls of the oblique comb electrodes, which are fabricated using silicon deep reactive ion etching followed by crystalline wet etching. The surface roughness was reduced from 200 (Rrms) to 20 nm (Rrms), and the verticality was improved from 88.7° to 89.7°. The capacitance change of the fabricated inclinometer experimentally ranges from -0.793 to 0.783 pF for the full range of inclination angle (from -90° to 90°). The estimated worst resolution, which is obtainable at an inclination angle of ±85°, was as low as 0.25°.

We propose the use of a self-aligned epoxy microbridge with a metal layer for a low-cost, easy-to-make inline fiber optic chemical sensor that can sense the concentration of chemical solutions. The key component of the sensor is a cylindrical epoxy microbridge that can be assembled between input and output optical fibers by self-aligned UV curing. The microbridge is made from an epoxy that can rapidly diffuse liquid. The top of the microbridge was coated with Au/Ti to block diffusion of the surrounding solution and to induce optical dissipation that depends on the concentration of the chemical solution. We tested our fiber optic chemical sensor for deionized (DI) water and NaCl solution. The medium surrounding the microbridge asymmetrically diffuses into the epoxy microbridge due to the metal layer. The asymmetrical diffusion, consequently, makes a major change to the refractive index on the bottom of the microbridge, thereby altering the propagation mode of light. As a result, depending on the concentration of the NaCl solution, a fraction of the propagated light is absorbed into the metal layer. The sensitivity, which refers to the ratio of the concentration change and optical power, was experimentally confirmed to be 0.103 (wt%/photon count)

We report on a novel refractive variable optical attenuator with a wedge-shaped silicon optical leaker, in which a part of the light signal is successively transmitted and refracted outside the acceptance angle of the output fiber. This device can be simply fabricated using a deep reactive ion etching and does not require sidewall metallization. We have theoretically estimated its optical characteristics and experimentally showed its high performances, such as low insertion loss of 0.6 dB and wide attenuation range of 43 dB. The fabricated device also showed a high return loss of over 39 dB even in an air-ambient condition and its polarization-dependent loss was smaller than 10% of the attenuation level.