Monitoring of neck activity for early warning of cervical spondylosis

<abstract> <p>Wireless body area networks (WBANs) is a new research hotspot with great development prospects. The non-contact sensing based on radio frequency signal can solve the issues of personal comfort and privacy. Detection of cervical motion range and cervical strain in time are important in diagnosis and prevention of cervical spondylosis. In this paper, channel state information is used to achieve smart perception and monitoring, timely and efficient detection of different postures and abnormal bending of the neck. It provides an efficient way for protecting cervical health, and also some help for doctors to understand the causes of cervical vertebral disease in a timely manner. The classification accuracy of the four activities reached 99.4%, 99.7%, 99.5% and 99.3%, respectively.</p> </abstract>

Biomimetic Artificial Joints Based on Multi-Material Pneumatic Actuators Developed for Soft Robotic Finger Application

To precisely achieve a series of daily finger bending motions, a soft robotic finger corresponding to the anatomical range of each joint was designed in this study with multi-material pneumatic actuators. The actuator as a biomimetic artificial joint was developed on the basis of two composite materials of different shear modules, and the pneumatic bellows as expansion parts was restricted by frame that made from polydimethylsiloxane (PDMS). A simplified mathematical model was used for the bending mechanism description and provides guidance for the multi-material pneumatic actuator fabrication (e.g., stiffness and thickness) and structural design (e.g., cross length and chamber radius), as well as the control parameter optimization (e.g., the air pressure supply). An actuation pressure of over 70 kPa is required by the developed soft robotic finger to provide a full motion range (MCP = 36°, PIP = 114°, and DIP = 75°) for finger action mimicking. In conclusion, a multi-material pneumatic actuator was designed and developed for soft robotic finger application and theoretically and experimentally demonstrated its feasibility in finger action mimicking. This study explored the mechanical properties of the actuator and could provide evidence-based technical parameters for pneumatic robotic finger design and precise control of its dynamic air pressure dosages in mimicking actions. Thereby, the conclusion was supported by the results theoretically and experimentally, which also aligns with our aim to design and develop a multi-material pneumatic actuator as a biomimetic artificial joint for soft robotic finger application.

Penerapan Latihan ROM (RANGE OF MOTION) Terhadap Rentang Gerak Ekstremitas Pada Pasien Stroke

Stroke is a disease caused by an acute neurological deficit in blood vesseldisorders leading to the brain that occur suddenly and can cause physical disability or death.The common complain are mobility impairment or decreased range of movement of the extremities.This study aimed to increase the range of movement of the extremities by doing Range on Motion exercises in families who have a history of stroke.There are two post-stroke patients involved in this study and give the Range of Motion exercise.The method used is to measure the degree of joint range of motion before performing ROM exercises then ROM exercises ranging from flexion, extension, hyperextension, adduction, abduction, and so on then measure the degree of joint range of motion with a goniometer measuring instrument and the results are recorded on the observation sheet.Goniometer was used to measurement the range of movement of the extremities.Range of Motion was performed for 7 days, each movement of 10 seconds duration.The results show that the range of movement increased in both patients. Accordingly, the Range of Motion exercises proved can increase the range of movement of the extremities in stroke patients.Families are expected to doing the Range of Motion exercise independently at home.Keywords:Range of motion; Range of movement; Stroke. AbstrakStroke adalah penyakit yang disebabkan oleh defisit neurologis akut pada gangguan pembuluh darah menuju otak yang terjadi secara tiba-tiba dan dapat menyebabkan kecacatan fisik atau kematian.Keluhan yang sering dikeluhkan adalah gangguan mobilitas atau penurunan jangkauan gerak ekstremitas. Penelitian ini bertujuan untuk meningkatkan jangkauan gerak ekstremitas dengan melakukan latihan Range on Motion pada keluarga yang memiliki riwayat stroke.Ada dua pasien pasca stroke yang terlibat dalam penelitian ini dan memberikan latihan Range of Motion.Metode yang dilakukan mengukur derajat rentang gerak sendi sebelum dilakukan latihan ROM kemudian latihan ROM mulai dari gerakan fleksi, ekstensi, hiperekstensi, addukksi, abduksi, dan lain sebagainya kemudian mengukur kembali derajat rentang gerak sendi dengan alat ukur goniometer dan hasilnya catat dilembar observasi.Goniometer digunakan untuk mengukur jangkauan gerakan ekstremitas.ROM dilakukan selama 7 hari, setiap gerakan durasi 10 detik.Hasil penelitian menunjukkan bahwa rentang gerak meningkat pada kedua pasien. Dengan demikian, latihan Range of Motion terbukti dapat meningkatkan jangkauan gerak ekstremitas pada pasien stroke. Keluarga diharapkan melakukan latihan Range of Motion secara mandiri di rumah.Kata kunci:Range of motion; Rentang gerak; Stroke.

Design and analysis of a novel large-range 3-DOF compliant parallel micromanipulator

Compared with the traditional rigid mechanism, the flexible mechanism has more advantages, which play an important role in critical situations such as microsurgery, IC (integrated circuit) fabrication/detection, and some precision operating environment. Especially, there is an increasing need for 3-DOF (degrees-of-freedom) compliant translational micro-platform (CTMP) providing good performance characteristics with large motion range, low cross coupling, and high spatial density. Decoupled topology design of the CTMP can easily realize these merits without increasing the difficulty of controlling. This paper proposes a new three DOF compliant hybrid micromanipulator which have large range of motion up to 100 μm × 100 μm × 100 μm in the direction in the dimension of 90 mm × 90 mm × 50 mm, smaller cross-axis coupling (the max coupling only 2.5%) than the initial XY compliant platform in XY axial.

Finite analysis of stability between modified articular fusion technique, posterior lumbar interbody fusion and posteriorlateral lumbar fusion

Background It is not clear whether modified facet fusion (MFF) is biomechanically different from traditional fusion techniques such as posterior lateral lumbar fusion (PLF) and posterior lumbar interbody fusion (PLIF). Methods In this study, a healthy adult Chinese male volunteer was selected to perform 3D reconstruction of CT image data and simulate the successful fusion of L4–5 MFF, PLF and PLIF, respectively. The motion range of L4–5 segments of the model was simulated under 6 working conditions, including forward flexion, extension, lateral flexion and rotation under normal physiological conditions, and the stability of the three fusion procedures in the pathological segments of the lumbar spine was compared. Results There was no difference in range of motion between MFF model and PLF or PLIF model (P < 0.05). Also, the stiffness of the PLFand the MFF model were comparable (P > 0.05), but were smaller than the PLIF model (P < 0.05). Conclusions MFF provides reliable stability at the lumbar fixation fusion level and does not differ significantly from PLF and PLIF in terms of range of motion.

The influence of gravity on respiratory kinematics during phonation measured by dynamic magnetic resonance imaging

Respiratory kinematics are important for the regulation of voice production. Dynamic MRI is an excellent tool to study respiratory motion providing high-resolution cross-sectional images. Unfortunately, in clinical MRI systems images can only be acquired in a horizontal subject position, which does not take into account gravitational effects on the respiratory apparatus. To study the effect of body posture on respiratory kinematics during phonation, 8 singers were examined both in an open-configuration MRI with a rotatable gantry and a conventional horizontal MRI system. During dynamic MRI the subjects sang sustained tones at different pitches in both supine and upright body positions. Sagittal images of the respiratory system were obtained at 1–3 images per second, from which 6 anatomically defined distances were extracted to characterize its movements in the anterior, medium and posterior section of the diaphragm as well as the rip cage (diameter at the height of the 3rd and 5th rip) and the anterior–posterior position of the diaphragm cupola. Regardless of body position, singers maintained their general principles of respiratory kinematics with combined diaphragm and thorax muscle activation for breath support. This was achieved by expanding their chest an additional 20% during inspiration when singing in the supine position but not for sole breathing. The diaphragm was cranially displaced in supine position for both singing and breathing and its motion range increased. These results facilitate a more realistic extrapolation of research data obtained in a supine position.

2-DOF Small-Size Piezoelectric Locomotion Platform with the Unlimited Motion Range

This paper presents numerical and experimental investigations of a small size piezoelectric locomotion platform that provides unlimited planar motion. The platform consists of three piezoelectric bimorph plates attached to the equilateral triangle-shaped structure by an angle of 60 degrees. Alumina spheres are glued at the bottom of each plate and are used as a contacting element. The planar motion of the platform is generated via excitation of the first bending mode of the corresponding plate using a single harmonic signal while the remaining plates operate as passive supports. The direction of the platform motion controlled by switching electric signal between piezoelectric plates. A numerical investigation of the 2-DOF platform was performed, and it was found out that the operation frequency of the bimorph plates is 23.67 kHz, while harmonic response analysis showed that the maximum displacement amplitude of the contact point reached 563.6 µm in the vertical direction while an excitation signal of 210 Vp-p is applied. Prototype of the 2-DOF piezoelectric platform was made, and an experimental study was performed. The maximum linear velocity of 44.45 mm/s was obtained when preload force and voltage of 0.546 N and 210 Vp-p were applied, respectively.

A flexure-based linear guide with torsion reinforcement structures

In this work, a flexure-based (compliant) linear guide with a motion range comparable to its footprint is presented. The design consists of two folded leaf springs on which torsion reinforcement structures are added. Due to these structures, only two folded leaf springs are needed instead of a minimum of five as in pre-existing designs. The new design is compared to such a pre-existing design, after optimizing both on a support stiffness metric. The new design scores over twice as high on the support stiffness metric, while occupying a smaller (−33%) and a less obstructive build volume. Stress, build volume and manufacturing limitations are taken into account. Additionally, a variation on the new design using three torsion reinforced folded leaf springs is presented and optimized. This design occupies a build volume similar to the pre-existing design, but scores four times higher on the support stiffness metric. A prototype of the new design is built and its parasitic eigenfrequencies are measured, validating the theoretical models (Normalized Mean Absolute Error of 4.3%).

Design of a Single-Material Complex Structure Anthropomorphic Robotic Hand

In the field of robotic hand design, soft body and anthropomorphic design are two trends with a promising future. Designing soft body anthropomorphic robotic hands with human-like grasping ability, but with a simple and reliable structure, is a challenge that still has not been not fully solved. In this paper, we present an anatomically correct robotic hand 3D model that aims to realize the human hand’s functionality using a single type of 3D-printable material. Our robotic hand 3D model is combined with bones, ligaments, tendons, pulley systems, and tissue. We also describe the fabrication method to rapidly produce our robotic hand in 3D printing, wherein all parts are made by elastic 50 A (shore durometer) resin. In the experimental section, we show that our robotic hand has a similar motion range to a human hand with substantial grasping strength and compare it with the latest other designs of anthropomorphic robotic hands. Our new design greatly reduces the fabrication cost and assembly time. Compared with other robotic hand designs, we think our robotic hand may induce a new approach to the design and production of robotic hands as well as other related mechanical structures.

Effect of a Jet Control Device on the Process of Missile and Internal Weapons Bay Separation

To ensure that the missile is safely separated from the internal weapons bay, the jet is used to control the process of missile separation, which is mounted on the front edge of the bay. The length-to-depth ratio of the bay was L/D=8, the diameter of the missile was d1 =0.178 m, the diameter of the jet was d2 =0.05 m . The FLUENT software was combined with our group-developed code under the platform of a user-defined function (UDF) to solve the flow field and the six-degrees-of-freedom (6DOF) of missile. The detached eddy simulation method and dynamic mesh technology were used in the numerical calculations. The boundary condition of missile, bay, and aircraft was no-slip wall condition. The boundary condition of the jet was the pressure-inlet. The pressure far-field boundary was selected as other boundaries. The constraint of the ejection device on the missile was considered. It was found that the jet control device thickens the shear layer, so the shear layer with more gradual velocity gradients, which is beneficial to the separation of missile. The distance between the internal weapons bay and the missile in the positive z-direction with the jet is 1.74 times that without the jet at t=0.5 s. In the case of the jet control device, the pitching angle of the missile ranged from 0.93° to -3.94° , the angular motion range of the missile with the jet is smaller than that without. The jet can make the characteristics of the flow field friendly, and enable the missile to separate from the bay quickly, stably, and safely.