Model Of Arm Research Articles

Development of Teaching Materials to Examine the Relationship Between the Structure and Function of Bones and Muscles: Arm Models

Development of Teaching Materials to Examine the Relationship Between the Structure and Function of Bones and Muscles: Arm Models

Analysis of stress distribution in lingual orthodontics system for effective en-masse retraction using various combinations of lever arm and mini-implants: A finite element method study

The aims and objectives of this study were to evaluate the von Mises stress and principal stress distribution and displacement of anterior teeth in a lingual orthodontics system along the periodontal ligament and alveolar bone by various combinations of mini-implants and lever arm during en-masse retraction. Four 3-dimensional finite element (FE) models of the bilateral maxillary first premolar extraction cases were constructed. Lingual brackets were (0.018-in slots) positioned over the center of the clinical crown. In all 4 models, 150g of retraction force was applied with the help of a nickel-titanium closed coil spring with different combinations of mini-implants and lever arm on each side. FE analysis was then performed to evaluate stress distribution, principal stress, von Mises stress, and displacement of the anterior teeth using ANSYS software (version 12.1; Ansys, Canonsburg, Pa). The FE study was enough to validate the analysis results obtained by software tools with FE simulation instead of experimental readings. Thus, statistical analysis was not required. In this study, maximum tensile stresses were observed in the periodontal ligament at the mesial cervical region of the canine with values of 1.84MPa, 2.02MPa, 1.88MPa, and 2.08MPa for models 1-4, respectively. Maximum von Mises stress in alveolar bone was 8.05MPa, 8.23MPa, 8.19MPa, and 8.37MPa for models 1-4, respectively, which was within the optimum limit (135MPa). Variable amounts of displacements like lingual crown tipping, lingual root tipping, and extrusion were observed in all the models. The 15-mm long lever arm models (models 2 and 4) showed a more controlled crown (0.015mm) and root movement (0.004mm) compared with 12-mm long lever arm models (models 1 and 3). In lingual orthodontics, controlled root movement increased as we increased the length of the lever arm. It was also concluded that the amount of increased controlled tipping found with the placement of the mini-implant was toward the palatal slope.

Robust $\mathcal {H}_{\infty }$-Based Control for Uncertain Stochastic Fuzzy Switched Time-Delay Systems via Integral Sliding Mode Strategy

In this article, we investigate the problems of robust exponential stabilization in mean square and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathcal {H}_{\infty }$</tex-math></inline-formula> -based integral sliding mode controller design for uncertain stochastic Takagi–Sugeno (T-S) fuzzy switched time-delay systems with both matched and unmatched uncertainties under synchronous switching and asynchronous switching, respectively. In these systems, the control input is dependent on a switching signal. Under synchronous switching and asynchronous switching, sufficient conditions are developed to guarantee that the resulting closed-loop systems are robustly exponentially stable in mean square with a prescribed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathcal {H}_{\infty }$</tex-math></inline-formula> -performance, respectively. The integral sliding mode surfaces and the sliding mode controllers are designed for the underlying systems under synchronous switching and asynchronous switching, respectively. By two examples stemming from the mass–spring–damper model and the single-link robot arm model under stochastic perturbation, the effectiveness of the results obtained is verified.

Magnetic needle-tracking device for ultrasound guidance of radial artery puncture: A randomized study on a simulation model.

Ultrasound-guidance of radial artery catheter insertion improves the first attempt success and reduces the occurrence of hematomas. Needle-tracking devices optimize needle-ultrasound beam alignment by displaying in real-time the needle tip position. We compared the median time need by experienced physicians to achieve radial artery puncture using either a conventional ultrasonography device (CUD) or a magnetic needle-tracking ultrasound device (MUD) in a simulation training arm model. Fifty experienced residents and physicians performed two punctures in randomized order with the CUD and the MUD. The primary outcome was puncture duration; the secondary outcomes were puncture success, rate of accidental vein puncture, and practitioner's comfort (subjective scale 0-10). The median [lower-upper quartile] puncture time was 10 [6-14] seconds when using CUD and 4 [3-7] seconds when using MUD (P < .01). In the multivariate analysis, MUD use was associated with decreased puncture duration whatever the puncture order (OR 1.13 [1.07-1.20], P < .01). The participants performed 99 (99%) successful punctures: 50 with the MUD (100%) and 49 with the CUD (98%). There was no accidental venous puncture. The practitioner's comfort level was 6.5 [6, 7] with the CUD and 8 [7-9] with the MUD (P < .01). MUD reduced radial artery puncture time and improved physician comfort in a simulation training arm model.

Economic rationale on the use of m-Health in uncontrolled hypertensive outpatients: from three months and beyond

Abstract Background/Introduction Current scientific data show that blood pressure (BP) telemonitoring with/without additional counseling is rather effective in hypertension (HTN) management. However, cost-effectiveness and long-term social sequelae are lacking. This is because of diverse technologies and economic climate which make results highly heterogeneous across countries. Purpose To construct predictive model of long-term outcomes and to conduct the cost-effectiveness analysis of BP telemonitoring and remote counseling (BPTM) using m-Health in Russian population of outpatients with HTN. Methods Total of 240 patients were randomized (2:1) to either BPTM (n=160, mean age 47 y.o.) and to usual care (UC, n=80, mean age 49 y.o.) with baseline, three-month follow-up clinic visits combined with ambulatory BP measurement (ABPM). BPTM consisted of m-Health tool for patients, desktop module for clinicians. It enables BP data transfer and analysis, secure web chatting to support and counsel. Main outcomes were change in office, ambulatory systolic (S) BP and rate of BP control. A Markov cohort-based (1000 patients per study arm) model was developed and adopted a 10-year time horizon with 12-month time cycles. All patients started at a non-complicated HTN “well” state with a certain possibility of disease progression in a number of health states over a discrete time period. BPTM was compared with usual care in terms of 10-year healthcare costs, quality adjusted life years (QALY) using a Ministry of Health of Russian Federation perspective. Incremental cost-effectiveness ratio (ICER), incremental cost-utility ratio (ICUR) represented economic analysis. Results BPTM was associated with steeper decrease in office, ambulatory SBP (−16,8 mm Hg and −8,9 mm Hg, respectively; p&amp;lt;0,05) with the same treatment intensity (2,4 drugs per patient). There were 102 (64%) and 11 (14%) patients with fully controlled HTN in BPTM and UC groups, respectively (OR 11,03 95% CI [5,4–22,5]). An ICER of BPTM resulted in additional 11,1 EUR/1 mm Hg/year. It is expected that BPTM will be at least 76% cost-effective as per relevant Russian willingness-to-pay threshold. In a modelled 10-year period BPTM was life-saving (9,71 vs 9,6 life years gained) and cheap (cost of illness 1,5 mln vs 2,1 mln EUR). BPTM was also more valuable (8,31 versus 7,82 QALYs gained) so the ICUR was 3601,47 EUR/QALY gained. Cost-effectiveness was further confirmed by one-way deterministic sensitivity analysis. Conclusion BPTM seems to be clinically and economically effective when implemented into clinical practice. It provides greater BP reduction, improves BP control short-term. In a long-term it is likely to reduce cardiovascular morbidity and mortality in a cost-effective way. Larger randomized studies are needed to confirm these pilot results. Cost-effectiveness acceptability curve Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): The Russian Scientific Foundation

Optimization of Linear Quadratic Tracking (LQT) Weight Matrices Using Simulated Annealing Applied on Planar Arm Model

Optimal controls have been applied in this time. One of simple optimal control which will be analyzed in this research is planar arm model dynamic. The planar arm model dynamic consists of joint angles consisting of shoulder joint and elbow joint, angle velocities, and joint torquest due to passive muscle forces. There are control inputs from six muscles in the system. In this research, from planar arm model, it will be designed optimal control using Linear Quadratic Tracking (LQT). The objective function of planar arm model is we will minimimize two angles consisting of shoulder joint and elbow joint. In LQT, the value of performance index depends on the weight matrices so that we should optimize the weight matrices. In this research, the optimization of weight matrices in planar arm model will be applied by Simulated Annealing. The Simulated Annealing method is based on the simulation of thermal annealing of critically heated solids. Based on simulation results, Simulated Annealing can optimize the weight matrices in LQT so that it results optimal performance index with angle as state solution can follow the reference and we also obtain optimal controls from six muscle forces applied.

Development of a Tetrahedral-Shaped Soft Robot Arm as a Wrist Rehabilitation Device Using Extension Type Flexible Pneumatic Actuators

Based on aging Japanese society, there has been a strong desire for development of rehabilitation devices that patients can use at home. The purpose of this study is to develop a home-based compact, lightweight, flexible, and safe rehabilitation device. In this study, a flexible robot arm for wrist rehabilitation that can be used, while patients hold the top of the robot arm, is proposed and tested. The proposed robot arm consists of three extension type flexible pneumatic actuators (EFPAs) restrained by 22 PET sheets. To achieve suitable bending stiffness of the robot arm, three EFPAs are restrained so as to form a tetrahedral shape. The robot arm can bend toward each radial direction. In this paper, the construction and operational principles of the tested robot arm are described. Additionally, the analytical model of the robot arm for attitude control is also described. In addition, the tracking control using the robot arm for the desired orbit is performed. As a result, the tested robot arm can trace the desired orbit based on the model. It is confirmed that the robot arm has the possibility for application as a wrist rehabilitation device for patients.

Target dynamic grasping during mobile robot movement based on learning methods

Purpose One of the development trends of robots is to enable robots to have the ability of anthropomorphic manipulation. Grasping is the first step of manipulation. For mobile manipulator robots, grasping a target during the movement process is extremely challenging, which requires the robots to make rapid motion planning for arms under uncertain dynamic disturbances. However, there are many situations require robots to grasp a target quickly while they move, such as emergency rescue. The purpose of this paper is to propose a method for target dynamic grasping during the movement of a robot. Design/methodology/approach An off-line learning from demonstrations method is applied to learn a basic reach model for arm and a motion model for fingers. An on-line dynamic adjustment method of arm speed for active and passive grasping mode is designed. Findings The experimental results of the robot movement on flat, slope and speed bumps ground show that the proposed method can effectively solve the problem of fast planning under uncertain disturbances caused by robot movement. The method performs well in the task of target dynamic grasping during the robot movement. Originality/value The main contribution of this paper is to propose a method to solve the problem of rapid motion planning of the robot arm under uncertain disturbances while the robot is grasping a target in the process of robot movement. The proposed method significantly improves the grasping efficiency of the robot in emergency situations. Experimental results show that the proposed method can effectively solve the problem.

Upper Limbs Kinematics Estimation Using Affordable Visual-Inertial Sensors

This study aims at developing and evaluating an affordable and user-friendly motion capture system for human upper limbs’ joint kinematics estimation. The objective is to provide quantitative assessments during the clinical evaluation of poststroke patients performing daily living activities. The proposed system is based on the simultaneous use of affordable inertial measurement units, and a set of augmented reality markers tracked with an affordable RGB camera. Two practical calibration processes were developed to calibrate the sensors modules and then to determine their location on body segments. Then, all measured quantities were fused into a constrained extended Kalman filter based on an upper limbs’ biomechanical model. The proposed system was validated with nine healthy volunteers performing five daily living activities. Joint angles estimated using the proposed affordable system were compared with a gold standard stereophotogrammetric system. The results showed a low average rms difference (2.7°) along with a high average correlation (0.87). <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —This article was motivated by the problem of assessing human upper limbs’ mobility during a rehabilitation process. Existing systems are often inaccurate and/or not affordable. This article suggests a new approach by combining measurements from inertial measurement units and augmented reality markers into an adaptive filter that is taking into account the kinematics model of the human arm and its limitation to filter out unfeasible solutions. The system is also making use of a new very practical calibration method not requiring any external equipment while remaining very affordable. Experimental results suggest that the proposed system is able to estimate more accurately than state-of-the-art joint angles of the upper limbs.

Design and Kinematics Analysis for a Cable-driven Underwater Snake Arm Robot

Aiming at the problem that underwater manipulators are mostly rigid structures and cannot meet the requirements of flexible operations, this paper designs and studies a cable-driven underwater snake arm robot. The snake arm is composed of multiple rigid links connected in series, and the joint rotation is realized by controlling the change of the length of the driving cable, which can effectively solve the problem that the traditional underwater manipulator has poor flexibility and cannot work in a narrow space. In this paper, the 3-D model of the cable-driven underwater snake arm is carried out, the mapping relations among driving space, joint space and operation space are analyzed.

Asynchronous Feedback Control for Delayed Fuzzy Degenerate Jump Systems Under Observer-Based Event-Driven Characteristic

This article is concerned with the issue of asynchronous feedback control for fuzzy degenerate jump systems with mode-dependent time-varying delays via Takagi–Sugeno fuzzy control technique under observer-based event-driven characteristic. The improved observer and event trigger transmit not only state estimate signals but also the information of Markovian jump modes to the controller under the networked nonperiodic sampling scheme. Applying parallel distributed compensation technique, the asynchronous fuzzy feedback controller is devised, and the asynchronous fuzzy controller modes are depicted by a hidden Markovian model, where the modes of fuzzy controller run asynchronously with that of the original degenerate fuzzy jump systems. Exponentially decreasing function is employed to devise the triggering threshold, which can ensure not only the admissibility of the delayed fuzzy degenerate jump systems but also the effectiveness of event-driven strategy. Original stochastic admissibility and asynchronous feedback control conditions are characterized by linear matrix inequalities. A numerical example and a single-link robot arm model are applied to illustrate the correctness and validity of the proposed observer-based event-driven asynchronous fuzzy feedback control technique.

Fuzzy Model-Based Asynchronous Control for Markov Switching Systems with Stochastic Fading Channels

This work investigates the asynchronous control for fuzzy Markov switching systems (MSSs) with randomly occurring fading channel. By resorting to a T-S fuzzy model, the nonlinear MSSs can be handled. Meanwhile, in the unreliable network, the Rice fading model is proposed to capture the randomly occurring channel fading, which covers packet dropouts and network-induced delays as special cases. In light of the hidden Markov model, the asynchronous phenomenon of controller is taken into consideration, and asynchronous fuzzy controller is obtained. In the end, a numerical example and a single-link robotic arm model are applied to demonstrate the validity of the derived results.

How do different spiral arm models impact the ISM and GMC population?

ABSTRACT The nature of galactic spiral arms in disc galaxies remains elusive. Regardless of the spiral model, arms are expected to play a role in sculpting the star-forming interstellar medium (ISM). As such, different arm models may result in differences in the structure of the ISM and molecular cloud properties. In this study, we present simulations of galactic discs subject to spiral arm perturbations of different natures. We find very little difference in how the cloud population or gas kinematics vary between the different grand design spirals, indicating that the ISM on cloud scales cares little about where spiral arms come from. We do, however, see a difference in the interarm/arm mass spectra, and minor differences in tails of the distributions of cloud properties (as well as radial variations in the stellar/gaseous velocity dispersions). These features can be attributed to differences in the radial dependence of the pattern speeds between the different spiral models, and could act as a metric of the nature of spiral structure in observational studies.

Design and Development of Bio-Sensitive Robotic Arm using Gesture Control

In this paper, a model of a robotic arm is designed and manufactured using a 3D printer, which is to be operated via human gesture by using the Accelerometer and Gyroscope Module. This arm is proposed to help in the medical field, in military operations, in hazardous conditions and in industries to maximize human safety. The robot arm is designed such that, it has 5 degrees of freedom controlled by the 3-axis accelerometer mounted on the IC placed on the glove of the user. The module will replicate the movement of the user’s hand to extend, retract, and rotate accordingly to accurately position as required for the application. The user’s finger action is used to manipulate the working of the gripper. Therefore, gesture control in a broad sense is a computerized interface that allows computers to record and interpret those gestures into commands to adhere to actions.

Linear-Quadratic Optimal Boundary Control of a One-Link Flexible Arm

A linear-quadratic optimal control problem is considered for the infinite-dimensional model of a one-link flexible arm. Two boundary inputs are assumed to be available, namely the joint torque at the link base and a transverse force at the tip of the link. The problem is formulated and solved using semigroup theory and duality arguments. Simulation results are provided to support the theoretical findings, comparing the proposed optimal LQ law with a more conventional PD/state feedback controller in terms of cost and transient performance.

Fault-Tolerant Fuzzy Control for Semi-Markov Jump Nonlinear Systems Subject to Incomplete SMK and Actuator Failures

This article focuses on the problem of fuzzy-model-based fault-tolerant control for nonlinear semi-Markov jump systems in the discrete-time context. The discrete-time semi-Markov process is employed to describe the mode jumping among several subsystems in the investigated systems. Moreover, the nonlinear characteristics are effectively tackled through utilizing the Takagi–Sugeno fuzzy model. Unlike some previous results, the information of the semi-Markov kernel (SMK) in this article is assumed to be partially available, which conforms better with the practical scenarios. Besides, considering the case that actuators may encounter some unexpected failures during system operation, the fault-tolerant mechanism is introduced in the process of controller design to enhance the fault tolerance of the studied systems. By means of SMK approach and Lyapunov stability theory, some elapsed-time-dependent criteria for guaranteeing the mean-square stability of the closed-loop system are established. According to these criteria, the design methodology of the reliable fuzzy state feedback controller is developed. Eventually, in order to verify the practicability and rationality of the developed control scheme, a single-link robot arm model is presented.

Finite element modal analysis and harmonic response analysis of human arm grasping model

Based on CT scan, the finite element models of human arm were constructed. Modal analysis of the arm was performed, and the natural vibration characteristics were evaluated. The dynamic simulation of the vibration transmission process was carried out when grasping the handle, and the vibration response and transmission characteristics were investigated. Resonance was likely to occur in the ranges of 5–10 Hz and 35–40 Hz, which caused fatigue damage to the arm. Vibrations in the ranges should be avoided having direct contact with the handle. The analysis results were found to be consistent with those of modal analysis.

DESIGN, MODELLING AND ANALYSIS OF INDUSTRIAL ROBOTIC ARM MINIMIZING WEIGHT AND CAPITAL INVESTED

This paper presents the design, modelling and analysis of a robotic arm to minimize weight and capital invested.The major reason for the initiation of this project is the fact that the manufacturing industry is growing at relatively faster rate. Most companies in today’s world prefer the usage of high load robotic arm,very few companies create light weight, and affordable robotic arm. As a result, small scale industries are being affected. This contribution will show how materials such as aluminium alloy 356 can be used in building of lightweight robotic arm.In this process of modelling and analysis,the finite element method would be very helpful in the early stage of design. The result of this analysis will give us a picture about which material will be best suited for making lightweight robotic arm.It also gives us the strength and weakness of each material The SolidWorks software was being used to design and model the robotic arm, and to simulate the motion of the device.The finite element method was carried out using ANSYS® software workbench.This method studies the model of a robotic arm with different materials and various loading conditions

Parameter identification of additional forces and torques for simulated space manipulator in zero-g simulation system

In this paper, the strain expressions a manipulator arm are established. The strain expressions affected by gravity, suspension force and torque are considered as well. The arm model is simplified as a cantilever beam, which makes the derivation more concise. In addition, the strain gauges are set on the arm to collect the strain data when the manipulator operates. The parameters of additional forces and torques are identified. And the fitting curve is very close to the experimental data.

Muscle Synergy Control During Hand Reach Task on Varying Shoulder Configuration.

Control of human arm in reaching task is a result of complex neural interaction involving central nervous and musculoskeletal system, where, group of muscle activation are planned through synergistic and coordinated recruitment, often to reach an optimal strategy. Aim of this paper is to explore muscle synergy distribution on several reaching task of similar elbow trajectory but changing shoulder configuration. A musculoskeletal model of human arm comprising shoulder, elbow and wrist joint have been designed and is used to calculate muscle activation required to perform three specific reaching tasks. Muscle synergy have been computed on the simulated activation to find a relation between synergy and energy requirement with the change of rotation and elevation of shoulder and its effect on the motion path of the elbow joint. These findings may help to define optimal joint configuration for a planned range of motion during rehabilitation exercises and also in developing neural prosthesis and myoelectric interfaces for efficient arm motion control.