Finger Research Articles

Determinants of hand pulse wave velocity and hand pulse transit time in healthy adults

Arterial pulse wave velocity (PWV) is recognized as a convenient method to assess peripheral vascular stiffness. This study explored the clinical characteristics of hand PWV (hPWV) and hand pulse transit time (hPTT) in healthy adults (sixty males = 42.4 ± 13.9 yrs; sixty-four females = 42.8 ± 13.9 yrs) voluntarily participated in this study. The arterial pulse waveform and the anatomical distance from the radial styloid process to the tip of the middle finger of both hands were recorded in the sitting position. The hPWV was calculated as the traversed distance divided by hPTT between those two points. Male subjects showed significantly greater hPWV, systolic blood pressure, and pulse pressure than age-matched female subjects, while the hPTT was not significantly different between genders. Multiple linear regression analysis showed that gender is a common determinant of hPWV and hPTT, and that age and heart rate (HR) were negatively correlated with hPWV and hPTT, respectively. We conclude that male subjects have greater hPWV than female subjects. Ageing is associated with decreased hPWV, while increased HR is associated with a smaller hPTT. The hPWV and hPTT might be used as non-invasive indices to characterise the ageing and arterial stiffness of peripheral blood vessels.

Feasibility of Dark-Field Radiography to Enhance Detection of Nondisplaced Fractures.

Background Many clinically relevant fractures are occult on conventional radiographs and therefore challenging to diagnose reliably. X-ray dark-field radiography is a developing method that uses x-ray scattering as an additional signal source. Purpose To investigate whether x-ray dark-field radiography enhances the depiction of radiographically occult fractures in an experimental model compared with attenuation-based radiography alone and whether the directional dependence of dark-field signal impacts observer ratings. Materials and Methods Four porcine loin ribs had nondisplaced fractures experimentally introduced. Microstructural changes were visually verified using high-spatial-resolution three-dimensional micro-CT. X-ray dark-field radiographs were obtained before and after fracture, with the before-fracture scans serving as control images. The presence of a fracture was scored by three observers using a six-point scale (6, surely; 5, very likely; 4, likely; 3, unlikely; 2, very unlikely; and 1, certainly not). Differences between scores based on attenuation radiographs alone (n = 96) and based on combined attenuation and dark-field radiographs (n = 96) were evaluated by using the DeLong method to compare areas under the receiver operating characteristic curve. The impact of the dark-field signal directional sensitivity on observer ratings was evaluated using the Wilcoxon test. The dark-field data were split into four groups (24 images per group) according to their sensitivity orientation and tested against each other. Musculoskeletal dark-field radiography was further demonstrated on human finger and foot specimens. Results The addition of dark-field radiographs was found to increase the area under the receiver operating characteristic curve to 1 compared with an area under the receiver operating characteristic curve of 0.87 (95% CI: 0.80, 0.94) using attenuation-based radiographs alone (P < .001). There were similar observer ratings for the four different dark-field sensitivity orientations (P = .16-.65 between the groups). Conclusion These results suggested that the inclusion of dark-field radiography has the potential to help enhance the detection of nondisplaced fractures compared with attenuation-based radiography alone. © RSNA, 2024 See also the editorial by Rubin in this issue.

Artificial Fingertip with Embedded Fiber-Shaped Sensing Arrays for High Resolution Tactile Sensing.

Replication of the human sense of touch would be highly advantageous for robots or prostheses as it would allow an agile and dexterous interaction with the environment. The article presents an approach for the integration of a micro-electromechanical system sensing skin with 144 tactile sensors on a soft, human-sized artificial fingertip. The sensing technology consists of thin, 1D sensing strips which are wrapped around the soft and curved fingertip. The sensing strips include 0.5 mm diameter capacitive sensors which measure touch, vibrations, and strain at a resolution of 1 sensor/mm2. The method allows to leverage the advantages of sensing skins over other tactile sensing technologies while showing a solution to integrate such skins on a soft three-dimensional body. The adaptable sensing characteristics are dominated by the thickness of a spray coated silicone layer, encapsulating the sensors in a sturdy material. We characterized the static and dynamic sensing capabilities of the encapsulated taxels up to skin thicknesses of 600 μm. Taxels with 600 μm skin layers have a sensitivity of 6 fF/mN, corresponding to an ∼5 times higher sensitivity than a human finger if combined with the developed electronics. They can detect vibrations in the full tested range of 0-600 Hz. The softness of a human finger was measured to build an artificial sensing finger of similar conformity. Miniaturized readout electronics allow the readout of the full finger with 220 Hz, which enables the observation of touch and slipping events on the artificial finger, as well as the estimation of the contact force. Slipping events can be observed as vibrations registered by single sensors, whereas the contact force can be extracted by averaging sensor array readouts. We verified the sturdiness of the sensing technology by testing single coated sensors on a chip, as well as the completely integrated sensing fingertip by applying 15 N for 10,000 times. Qualitative datasets show the response of the fingertip to the touch of various objects. The focus of this article is the development of the sensing hardware and the basic characterization of the sensing performance.

Supramolecular hydrogels mediated by cucurbit[6]uril-modified Fe3O4 with self-healing, photothermal responsiveness and stretchability for flexible electronics

The development of supramolecular hydrogels with multifunction is in high demand. In this work, Fe3O4 hybrid supramolecular hydrogels were fabricated via dynamic host–guest interactions between the host molecule CB[6] and guest units. The “supramolecular crosslinker” formed by CB[6]-modified Fe3O4 (Fe3O4@CB[6]) nanoparticles, was used to generate a 3D network of supramolecular hydrogels. Results indicate that the tensile stress of the sample is 0.31 MPa, and the self-healing efficiency of the supramolecular hydrogels at room temperature is nearly 100% (fracture strain) after 48 h. The hydrogels exhibited a self-healing property without a loss of conductivity. Furthermore, these supramolecular hydrogels were used to detect the bending of human fingers and knees. The hybrid supramolecular hydrogels with photothermal responsiveness, self-healing, injectability, stretchability, conductive ability and biocompatibility, can find applications in flexible electronics.

Towards humanlike grasp in robotic hands: mechanical implementation of force synergies

In the field of robotic hands, finger force coordination is usually achieved by complex mechanical structures and control systems. This study presents the design of a novel transmission system inspired from the physiological concept of force synergies, aiming to simplify the control of multifingered robotic hands. To this end, we collected human finger force data during six isometric grasping tasks, and force synergies (i.e. the synergy weightings and the corresponding activation coefficients) were extracted from the concatenated force data to explore their potential for force modulation. We then implemented two force synergies with a cable-driven transmission mechanism consisting of two spring-loaded sliders and five V-shaped bars. Specifically, we used fixed synergy weightings to determine the stiffness of the compression springs, and the displacements of sliders were determined by time-varying activation coefficients. The derived transmission system was then used to drive a five-finger robotic hand named SYN hand. We also designed a motion encoder to selectively activate desired fingers, making it possible for two motors to empower a variety of hand postures. Experiments on the prototype demonstrate successful grasp of a wide range of objects in everyday life, and the finger force distribution of SYN hand can approximate that of human hand during six typical tasks. To our best knowledge, this study shows the first attempt to mechanically implement force synergies for finger force modulation in a robotic hand. In comparison to state-of-the-art robotic hands with similar functionality, the proposed hand can distribute humanlike force ratios on the fingers by simple position control, rather than resorting to additional force sensors or complex control strategies. The outcome of this study may provide alternatives for the design of novel anthropomorphic robotic hands, and thus show application prospects in the field of hand prostheses and exoskeletons.

Monte Carlo simulation of the effect of melanin concentration on light-tissue interactions in transmittance and reflectance finger photoplethysmography

Photoplethysmography (PPG) uses light to detect volumetric changes in blood, and is integrated into many healthcare devices to monitor various physiological measurements. However, an unresolved limitation of PPG is the effect of skin pigmentation on the signal and its impact on PPG based applications such as pulse oximetry. Hence, an in-silico model of the human finger was developed using the Monte Carlo (MC) technique to simulate light interactions with different melanin concentrations in a human finger, as it is the primary determinant of skin pigmentation. The AC/DC ratio in reflectance PPG mode was evaluated at source-detector separations of 1 mm and 3 mm as the convergence rate (Q), a parameter that quantifies the accuracy of the simulation, exceeded a threshold of 0.001. At a source-detector separation of 3 mm, the AC/DC ratio of light skin was 0.472 times more than moderate skin and 6.39 than dark skin at 660 nm, and 0.114 and 0.141 respectively at 940 nm. These findings are significant for the development of PPG-based sensors given the ongoing concerns regarding the impact of skin pigmentation on healthcare devices.

THIẾT KẾ, CHẾ TẠO GĂNG TAY HỖ TRỢ PHỤC HỒI CHỨC NĂNG CHO NGƯỜI KHUYẾT TẬT SỬ DỤNG CÁC NGÓN MỀM

This article presents the development and production process of a glove designed for rehabilitation, and enhancing object manipulation capabilities for individuals with hand mobility limitations, using soft finger design. The soft fingers are constructed from a composite structure consisting of silicone rubber material. An automated calculation program is created in Python and integrated with Abaqus/CAE software, enabling the concurrent exploration of numerous parameters governing the soft fingers to choose a rational design of glove. Experimental tests reveal that the error of the experiment and simulation results is less than 7.8%. Furthermore, these deformable soft fingers can closely mimic the contours of human fingers. Leveraging the successful construction of the soft fingers, a corresponding soft glove is manufactured. Preliminary validated experiments demonstrate the effectiveness of these soft gloves in aiding patients with diverse exercise rehabilitation. Additionally, they provide support for basic tasks such as grasping objects weighing approximately 600 grams.

A Triboelectric Nanogenerator-Based Wide Range Self-Powered Flexible Pressure Sensor

Self-powered flexible pressure sensors are needed in applications such as human-machine interaction. Here, we present a triboelectric nanogenerator (TENG) based self-powered flexible pressure sensor capable of operating over a wide-range of pressures (3.2 - 1176 kPa). The sensor exhibits excellent sensitivities in various regions of the pressure range, i.e., 3.16, 0.023 and 0.031 V/kPa in the low (1-10 kPa), medium-high (10-500 kPa) and ultra-high (>500 kPa) pressure regimes respectively. Stable and repeatable TENG responses are achieved for all three pressure regimes, and this is due to the way the real contact area at the TENG interface varies with contact pressure. These results highlight the potential for TENGs in a wide range of applications such as: detecting pressure in wearable devices, human-machine interface, biomedical and automotive applications. As a proof-of-concept, we have demonstrated the use of the presented device in applications such as detection of human and robot finger tapping, collection of human gait information, and detection of impact forces.

FETAL ANATOMY OF THE ARTERIES OF THE DORSUM OF THE HAND

Fetal anatomy of the upper extremity in today’s understanding is a set of morphological methods for studying the structure and topography of the structures of its separate areas in human fetuses from the standpoint of the norm and taking into account the forms of individual anatomical variability. Also, in recent decades, microsurgical anatomy has gained intensive development, in particular the hand, which allows studying the structure and topography of small anatomical structures – blood vessels and nerves, muscle tendons, their layer-by-layer relationship in normal anatomical formation, and pathological deviations depending on the needs of microsurgery.The purpose of the study was to fi nd out the sources of blood supply, topography, and branching areas of the arteries of the back of the hand in human fetuses. The study was conducted on the preparations of 18 human fetuses aged from 4 to 10 months using macromicroscopic preparation, injection of arterial vessels, and morphometry.In human fetuses, the arteries of the back of the hand are arranged in two layers. The surface layer of the arterial vessels of the back of the hand, as a rule, is formed by the radial and anterior interosseous arteries, and (or), less often, by the ulnar or posterior interosseous arteries without the formation of arterial arches or nets. The deep layer of the arteries of the back of the hand mostly forms the back carpal arch and is inseparably connected both with the arteries of the superfi cial layer of the back of the hand and with the palmar arterial arches.The arteries of the deep layer of the back part of the hand are mostly (69.5 % of cases) represented by the back arterial arch: 1) radial-i nterosseous; 2) radial-i nterosseous-ulnar; 3) radial- ulnar; in 25 % of observations – with the posterior carpal arterial network. In 5.5 % of cases, the posterior carpal arch or posterior carpal mesh was absent, and duplication of the deep palmar arterial arch was found. Variability of the sources of formation, the degree of development, and the number of dorsal common digital arteries were revealed in human fetuses.Own dorsal digital arteries, except for the arteries of the thumb, as a rule, reach only the level of the middle phalanx of the fi ngers, and then they become thinner, or end in the periosteum or arterial arch-shaped anastomoses of the fi rst interphalangeal joint, or end in the palmar digital arteries, which provide blood supply to the back surface of the distal parts of the fi ngers of the brush.

Nonlinear control of two fingers model for movement coordination

This research introduces an innovative methodology for the integrated modeling, simulation, and analysis of two fingers, with particular emphasis on their fundamental roles in everyday tasks. In this study, we provide two nonlinear control strategies, specifically Sliding Mode Control (SMC) and Feedback Linearization Control (FLC), to achieve accurate and stable finger movements. As mentioned earlier, the controllers are utilized in the context of a biomechanical model consisting of two fingers, each possessing two degrees of freedom. These controllers enable the coordination of flexion and extension movements. The research conducted in our study emphasizes the coordinated regulation of finger movements, enabling the achievement of flexion through the utilization of two nonlinear controllers. By implementing these sophisticated control mechanisms, we can effectively showcase our model’s fidelity in adhering to the physiological limitations inherent to human fingers in their natural state. In addition, the proposed controllers demonstrate sound mitigation of non-linearities, such as load variations, different velocities, positional changes, and damping forces. This approach presents several advantages, such as handling non-linearities, guaranteeing robustness, choosing suitable parameters, and conducting comparative analysis. In order to substantiate our findings, we develop the nonlinear model utilizing the MATLAB/Simulink software. The findings of our study demonstrate effective regulation and control of the two-finger model’s position. In our study, we were able to get flexion angles of [Formula: see text] rad and [Formula: see text] rad using the sliding mode control (SMC) technique, and flexion angles of [Formula: see text] rad and [Formula: see text] rad using the fuzzy logic control (FLC) technique, all within a time frame of 5 s. These results serve to illustrate the applicability and significance of our proposed methodology.

Online Auction System

An online auction is an auction which is held over the internet. It is a popular method for buying and selling products and services. Online Auction System s helps to customer to sell and buy product in best price. It is developed with the objective of making the system reliable, easier and fast. This application is used to sell the anything on the website from house. This application is used to sell the anything on the website from house. It developed with the objective of making the system reliable, easier and fast. The application is made as simple as surfing a website. There by non-technical persons can also interact with the processing on the application easily. An online auction project is a system that holds online auctions for various products on a website and serves sellers and bidders accordingly. The system is designed to allow users to set up their products for auctions and to register and bid for various products available for bidding. Auction is an online auction web site aimed at taking the auction to the finger tips of aspiring bidders there by opening up the doors of the "OPEN Auction House' to a wider cross section of Art Lovers and Antique Collectors. This site also acts as an open forum where buyers and sellers can come together and exchange their products. The site makes sure that the sellers get a fair deal and buyers get a genuine product.

Exploring the Factors Influencing Usage Behavior of the Digital Library Remote Access (DLRA) Facility in a Private Higher Education Institution in India

Digitalization has transformed the world and empowered education across the globe alike. Digital Library Remote Access (DLRA) facilities have empowered students, researchers and academicians to have uninterrupted and complete access to literature and scientific information on finger tips through a single window. In order to understand the factors influencing the digital library usage in a private Higher Education Institution of Eminence in India, the study employs non-probability sampling, convenience sample of 400 researchers and students of the deemed to be university. The results of the investigation substantiates that habit plays a crucial role in ascertaining the behavioral intention and the usage behavior of DLRA technology.

Tissue mimicking materials and finger phantom design for pulse oximetry.

Pulse oximetry represents a ubiquitous clinical application of optics in modern medicine. Recent studies have raised concerns regarding the potential impact of confounders, such as variable skin pigmentation and perfusion, on blood oxygen saturation measurement accuracy in pulse oximeters. Tissue-mimicking phantom testing offers a low-cost, well-controlled solution for characterizing device performance and studying potential error sources, which may thus reduce the need for costly in vivo trials. The purpose of this study was to develop realistic phantom-based test methods for pulse oximetry. Material optical and mechanical properties were reviewed, selected, and tuned for optimal biological relevance, e.g., oxygenated tissue absorption and scattering, strength, elasticity, hardness, and other parameters representing the human finger's geometry and composition, such as blood vessel size and distribution, and perfusion. Relevant anatomical and physiological properties are summarized and implemented toward the creation of a preliminary finger phantom. To create a preliminary finger phantom, we synthesized a high-compliance silicone matrix with scatterers for embedding flexible tubing and investigated the addition of these scatterers to novel 3D printing resins for optical property control without altering mechanical stability, streamlining the production of phantoms with biologically relevant characteristics. Phantom utility was demonstrated by applying dynamic, pressure waveforms to produce tube volume change and resultant photoplethysmography (PPG) signals. 3D printed phantoms achieved more biologically relevant conditions compared to molded phantoms. These preliminary results indicate that the phantoms show strong potential to be developed into tools for evaluating pulse oximetry performance. Gaps, recommendations, and strategies are presented for continued phantom development.

AIR CANVAS USING AI

People are using electronic devices like screens, where we can write, draw and represent various structures, symbols, arts, painting, etc. Either by using mouse or by typing. The project takes advantage of this gap and introduces a new system called the air canvas which focuses on developing a motion-to-text converter that can potentially serve as software for intelligent wearable devices which enables users to draw in mid- air using their hands. The system incorporates object detection techniques in OpenCV to track the hand position and allow real-time drawing. It will be a powerful means of communication for the deaf. All you have to do is think what you want to express or show, and then just move your finger accordingly. The existing project which allows us to draw using a stylus or pen this technology or methodology which takes a lot of process and time. Avoiding or decreasing these limitations we came up with this project that uses new technologies and easy methodologies like Mediapipe which is used to detect the hand gestures under the category of Computer Vision. We are using Python since it is easy to make use of the syntax and understanding the basics as well as it can be implemented in any OpenCV supported languages, NumPy to handle data related to strokes, shapes, or any other canvas elements and it can provide a convenient way to represent and manipulate image processing. Deque stores the strokes and make it visible in the canvas, Mask Window to mask the background and show the text. System Camera is used to track the hand and create drawings just by moving their fingers on the air in front of the camera in a certain distance according to what the user wants to express and this works by monitoring to determine the landmarks of hand, then the finger tips are taken for modes like selection, drawing and clearing the canvas. KEYWORDS: - Canvas, OpenCV, Python, Computer Vision, NumPy, Deque, Mask Window.

Design, Engineering Analysis, and Fabrication of a Prototype Electromechanical Finger Fixator Control System

This paper investigates a new external fixator system for treating finger contractures. This innovative system is electric and user-friendly, providing precise readings of the angles of diseased finger joints. Accurate measurements of the angles of the diseased finger joints can assist therapists and patients during rehabilitation procedures. The fixator consists of ten parts assembled using polyether-ether-ketone (PEEK) for the plastic components and stainless steel for the metal components. The design model was engineered, drawn, and analyzed using SolidWorks Computer-Aided Design software. The verification process utilizes finite element analysis to demonstrate that the maximum stress was lower than the yield strength of the chosen materials. As a result, the new device design is robust and stable enough to withstand the anticipated loading conditions of human fingers. Subsequently, a prototype was fabricated using advanced additive manufacturing technology, specifically fused deposition modeling (FDM). The proposed fixator is simple to control, reliable, easy to use, and reproducible. It enables device users to exercise their finger joints throughout the day without requiring the assistance of specialists.

Anatomically-Inspired Robotic Finger with SMA Tendon Actuation for Enhanced Biomimetic Functionality.

This research introduces an advanced robotic finger designed for future generalist robots, closely mimicking the natural structure of the human finger. The incorporation of rarely discussed anatomical structures, including tendon sheath, ligaments, and palmar plates, combined with the usage of anatomically proven 3D models of the finger, give rise to the highly accurate replication of human-like soft mechanical fingers. Benefiting from the accurate anatomy of muscle insertions with the utilization of Shape Memory Alloy (SMA) wires' muscle-like actuation properties, the bonding in-between the flexor tendons and extensor tendons allows for the realization of the central and lateral band of the finger anatomy. Evaluated using the computer vision method, the proposed robotic finger demonstrates a range of motion (ROM) equivalent to 113%, 87% and 88% of the human dynamic ROM for the DIP, PIP and MCP joints, respectively. The proposed finger possesses a soft nature when relaxed and becomes firm when activated, pioneering a new approach in biomimetic robot design and offering a unique contribution to the future of generalist humanoid robots.

Efficacy of 3D Printed Finger Prosthesis for patients affected with Hansen’s Disease to Restore Hand Function

Introduction The greek word LEPROSY was renamed by the term Hansen’s disease by Norwegian physician Gerhard Armauer Hansen. In 2009, WHO Goodwill Ambassador Yohei Sasakawa called for an end to usage of the word leprosy, since he described it as ‘an extremely damaging term’ that contributes to stigma and impacts human rights. Since 2010, leprosy mission gives assurance that the word is not condoned by media channels or used by public figures. HD ranges from mild to severe (based on one or more skin areas affected and damage caused to organs).There were 5.2 million people affected by leprosy globally, in 1980 but by 2020 this decreased to fewer than 2,00,000. Leprosy can affect people in many ways. The Cochrane database of systemic reviews , 2019 lists that 30% of people affected with leprosy experience nerve damage. People with untreated leprosy become visibly disfigured often have psychologic and social problems. Mosby’s Medical Dictionary 2009 defines trophic ulcers as “a pressure ulcer caused by external trauma to a part of body or by vascular insufficiency leading to loss of afferent nerve fibres. The most severe complications result from infection of the peripheral nerves, which causes deterioration of sense of touch and inability to feel pain and temperature. The nerve damage is reversible when treated early, but becomes permanent when appropriate treatment is not available for sufferer. Damage to nerves may cause loss of muscle function, leading to paralysis. It may also lead to sensation abnormalities or numbness, which may lead to additional infections, ulcerations, and joint deformities. Also, damage to peripheral nerves may cause muscle weakness that can result in deformities. M. leprae attacks nerve endings and destroys the body's ability to feel pain and injury. Without feeling pain, people with leprosy have an increased risk of injuring themselves. In some cases, autoamputation has been reported to affect the tip of fingers. People with peripheral nerve damage may unknowingly burn, cut, or otherwise harm themselves. Infected nerves may enlarge also &amp; this can be palpated. The fingers may be weakened, causing them to curve inward (claw hand). When therapeutic amputation is decided for a patient affected with HD, occupational therapist can suggest preserving as much of hand as possible, to prepare wearing 3D printed prosthesis. 3-D printing is a new rising technology, Objects made in 3D printing range from plastic figurines and mould patterns to steel machine parts and titanium surgical implants. Related to Hansen Disease, It facilitates manufacturing hand parts with irregular and uncommon geometric shapes. Freedom offered by 3D printing techniques has paved the way for the application of new design for best appearances. The advantages of 3D printing could be used to fabricate prosthetic hands based on the biological design principles. The purpose of this study is to assess efficacy of 3-D printed finger prosthesis to manipulate objects &amp; to restore hand function in HD clients.

Development of spray-dried powder hand sanitiser with prolonged effectivity

Since the outbreak of the COVID-19 pandemic, the use of hand sanitisers has become an inseparable part of our personal hygiene. However, the short-term effect and the need for frequent application are shortcomings that impair the overall protection. Another aspect is that repeated use of some products (typically alcohol-based) may cause skin irritation or eventually more severe health problems. This work proposes spray-drying as a suitable method for the preparation of swellable chitosan carriers, allowing for encapsulation and sustained release of antibacterial chlorhexidine digluconate as a model active substance. After application to hands, micron-sized particles preferentially accommodate space between epidermal ridges, protected against attrition. Thanks to their small size (d < 10 µm), particles are comfortable to carry since they are not recognisable by somatosensory receptors. The performance of formulations with various amounts of chlorhexidine and cross-linker was tested and compared with selected commercial disinfectants available on the Czech market (ethanol gel and alcoholic solution with chlorhexidine) against E.coli and S.epidermidis. The real-life performance was investigated with twelve volunteers performing various activities for up to 2 h. Finally, a replica of the human index finger with accurately captured micro-topology was proposed and compared with volunteers’ fingers concerning the total amount of adhered and detached particles.

Teleoperation of an Anthropomorphic Robot Hand with a Metamorphic Palm and Tunable-Stiffness Soft Fingers.

Teleoperation in soft robotics can endow soft robots with the ability to perform complex tasks through human-robot interaction. In this study, we propose a teleoperated anthropomorphic soft robot hand with variable degrees of freedom (DOFs) and a metamorphic palm. The soft robot hand consists of four pneumatic-actuated fingers, which can be heated to tune stiffness. A metamorphic mechanism was actuated to morph the hand palm by servo motors. The human fingers' DOF, gesture, and muscle stiffness were collected and mapped to the soft robotic hand through the sensory feedback from surface electromyography devices on the jib. The results show that the proposed soft robot hand can generate a variety of anthropomorphic configurations and can be remotely controlled to perform complex tasks such as primitively operating the cell phone and placing the building blocks. We also show that the soft hand can grasp a target through the slit by varying the DOFs and stiffness in a trail.

Distal planar rotary scanner for endoscopic optical coherence tomography.

Optical coherence tomography (OCT) is becoming a more common endoscopic imaging modality for detecting and treating disease given its high resolution and image quality. To use OCT for 3-dimensional imaging of small lumen, embedding an optical scanner at the distal end of an endoscopic probe for circumferential scanning the probing light is a promising way to implement high-quality imaging unachievable with the conventional method of revolving an entire probe. To this end, the present work proposes a hollow and planar micro rotary actuator for its use as an endoscopic distal scanner. A miniaturized design of this ferrofluid-assisted electromagnetic actuator is prototyped to act as a full 360° optical scanner, which is integrated at the tip of a fiber-optic probe together with a gradient-index lens for use with OCT. The scanner is revealed to achieve a notably improved dynamic performance that shows a maximum speed of 6500rpm, representing 325% of the same reported with the preceding design, while staying below the thermal limit for safe in-vivo use. The scanner is demonstrated to perform real-time OCT using human fingers as live tissue samples for the imaging tests. The acquired images display no shadows from the electrical wires to the scanner, given its hollow architecture that allows the probing light to pass through the actuator body, as well as the quality high enough to differentiate the dermis from the epidermis while resolving individual sweat glands, proving the effectiveness of the prototyped scanner design for endoscopic OCT application.