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    Fuzzy control of a hand rehabilitation robot to optimize the exercise speed in passive working mode

    , Article Studies in Health Technology and Informatics ; Vol. 163 , 2011 , pp. 39-43 ; 09269630 (ISSN) ; 9781607507055 (ISBN) Baniasad, M. A ; Akbar, M ; Alasty, A ; Farahmand, F ; Sharif University of Technology
    The robotic rehabilitation devices can undertake the difficult physical therapy tasks and provide improved treatment procedures for post stroke patients. During passive working mode, the speed of the exercise needs to be controlled continuously by the robot to avoid excessive injurious torques. We designed a fuzzy controller for a hand rehabilitation robot to adjust the exercise speed by considering the wrist angle and joint resistive torque, measured continuously, and the patient's general condition, determined by the therapist. With a set of rules based on an expert therapist experience, the fuzzy system could adapt effectively to the neuromuscular conditions of the patient's paretic hand.... 

    MEG based classification of wrist movement

    , Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 ; 2009 , Pages 986-989 ; 1557170X (ISSN) ; 978-142443296-7 (ISBN) Montazeri, N ; Shamsollahi, M. B ; Hajipour, S ; Sharif University of Technology
    Neural activity is very important source for data mining and can be used as a control signal for brain-computer interfaces (BCIs). Particularly, Magnetic signals of neurons are enriched with information about the movement of different part of the body such as wrist movement. In this paper, we use MEG (Magneto encephalography) signals of two subjects recorded during wrist movement task in four directions. Data were prepared for BCI competition 2008 for multiclass classification. Our approach for this classification problem consists of PCA as a noise reduction method, ULDA for feature reduction and various linear classifiers such as Bayesian, KNN and SVM. Final results (58%-62% for subject 1... 

    Wrist-RoboHab: A robot for treatment and evaluation of brain injury patients

    , Article IEEE International Conference on Rehabilitation Robotics, 27 June 2011 through 1 July 2011, Zurich ; 2011 ; 19457898 (ISSN) ; 9781424498628 (ISBN) Baniasad, M. A ; Farahmand, F ; Ansari, N. N ; Sharif University of Technology
    This article, introduces a new haptic robot, wrist-RoboHab, for upper limb rehabilitation of post stroke, orthopedic and Parkinson patients., The robot is designed for hand movement therapy and could be used for both treatment and evaluation purposes in three operational states; forearm supination/pronation, wrist flexion/extension and ulnar/radial deviation. At first the mechanical design and control system are described. Then the results of a case study are demonstrated. Clinical results, showed an improvement in Fugle-Meyer, AROM, power and the biomechanical assessment of the spasticity in a chronic patient. Furthermore, it was approved that the robot can have a good interaction with... 

    Design and Analysis of an Actuating Robot to Employ Manual Endo-Wrist Laparoscopic Instruments in a Robotic Surgery System

    , M.Sc. Thesis Sharif University of Technology Moradi, Mohammad Mahdi (Author) ; Farahmand, Farzam (Supervisor) ; Hoviattalab, Maryam (Co-Advisor)
    This research describes the design and analysis of an actuating robot to manipulate the disposable Endo-wrist robotic surgery instruments. Analyzing the mechanism of common manual Endo-wrist instruments, it was found that the rotations of handle of the instrument are transferred to its wrist using a snake-like element and four connecting cables. Based on this observation, a 2DOF parallel actuating robot was designed to rotate the instrument handle, in which the degrees of freedom are controlled by two linear spindle motors. The Inverse kinematic analysis of the manual instrument was performed by minimizing the potential energy of cables. Also the inverse kinematic solution of the actuating... 

    Mechanical design, fabrication, kinematics and dynamics modeling, multiple impedance control of a wrist rehabilitation robot

    , Article International Conference on Robotics and Mechatronics, ICROM 2015, 7 October 2015 through 9 October 2015 ; 2015 , Pages 290-295 ; 9781467372343 (ISBN) Sajadi, M. R ; Nasr, A ; Moosavian, S. A. A ; Zohoor, H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    Rehabilitation is the best approach for patients who suffer physical disability of their upper-limbs. Maintaining the intensity of exercise during treatment is the main factor that makes the robots suitable for rehabilitation since robots do not get tired and do the exercises with constant intensity under supervision of the doctor. Two main categories of rehabilitation robots are End-Effector based robots and wearable robots. According to the fact that most problems occur in need of rehabilitation for hand wrist area, in this paper a wearable rehabilitation robot has been developed for the wrist. Nowadays, wearable robots attract more attention than the other group. Wearable robots are... 

    Development of a Wrist PPG Probe for the Measurement of Radial Artery Diameter

    , M.Sc. Thesis Sharif University of Technology Keikhosravi, Adib (Author) ; Zahedi, Edmond (Supervisor)
    Inability of endothelial cells in responding to metabolic needs (endothelial dysfunction,) is a sign of heart diseases like atherosclerosis and vascular stenosis. Recently, a new method using finger PPG signal has been proposed to determine endothelial function in response to reactive hypertension (RH.) PPG-based endothelial function assessment results are not fully correlated with ultrasound FMD tests, and this is because of some auto-regulation phenomena in the fingertip. It is expected that such problems will not exist in larger arteries, like the radial artery. The goal of this project is to acquire the PPG signal from the radial artery as it is proportional to blood volume changes in... 

    Design and Implementation of an Activation Mechanism for Wristed Laparoscopic Instruments at Sina Robotic Surgery System

    , M.Sc. Thesis Sharif University of Technology Hanifeh, Shahrzad (Author) ; Farahmand, Farzam (Supervisor)
    Sina surgical system is a telesurgery robotic system which is capable of using the conventional laparoscopic tools. In order to provide the wrist degree of freedom and increase the surgical maneuverability, a mechanism is introduced here which enables Sina to use and activate the wristed laparoscopic instrument Laparo-Angle. At first, the kinematics and dynamics characteristics of Laparo-Angle were identified experimentally. This tool contains 4 degrees of freedom, pitch, yaw, grasp and distal Roll. Activation of pitch and Yaw degrees of freedom requires a mechanism which at least has two rotational degrees of freedom to move the tool handle in a cone shape workspace with an apex angle of 36... 

    Control of an Active Exoskeleton Robot to Assist Human Elbow and Wrist Motion

    , M.Sc. Thesis Sharif University of Technology Hejazi, Mahmoud (Author) ; Zohoor, Hassan (Supervisor) ; Behzadipour, Saeed (Co-Advisor)
    Most elderly and physically disabled people suffer from lack of functionality and dexterity in their elbow or wrist. These disabilities are due to the damages mostly caused by sport surgery, spinal surgery, or stroke. Therefore, design of an assistive exoskeleton robot for upper limb movements seems necessary. The purpose of this study is to design, fabricate and deliver a control algorithm for an assistive wearable robot. The robot has two degrees of freedom in order to help the flexion/extension of elbow and wrist. Furthermore, various kinds of control systems incorporated in rehabilitation robots are investigated and their advantages and drawbacks are compared. Then, some conventional... 

    Effect of deep breath on the correlation between the wrist and finger photoplethysmograms

    , Article 2012 19th Iranian Conference of Biomedical Engineering, ICBME 2012 ; 2012 , Pages 135-138 ; 9781467331302 (ISBN) Keikhosravi, A ; Zahedi, E ; Sharif University of Technology
    In this paper, a special probe is designed using an array of photodiodes and a 960 nm LED for recording the wrist photoplethysmogram (PPG). The design is based on Monte-Carlo simulation of light propagation in tissues. Two series of experiments were carried-out: normal breathing and deep breathing. In both experiments, finger and wrist PPG were simultaneously recorded from the index finger. In the first series of experiment, signals from 9 subjects were recorded and the correlation coefficient for the raw signals (AC+DC), the AC and DC components of wrist and finger PPG were (62.5% ± 12.1%), (91.2% ± 6.9%) and (61% ± 13.4%) respectively. In the second series of experiment (deep breathing),... 

    Design, Analysis, and Experimental Study of a Slave Robot for Minimally Invasive Beating Heart Surgery

    , Ph.D. Dissertation Sharif University of Technology Alamdar, Alireza (Author) ; Farahmand, Farzam (Supervisor)
    In this study, a practical approach for robotic beating heart surgery was proposed. This approach eliminates lateral movements of the heart and compensates for normal heart movement by using 1 DOF heart stabilizer and 1 DOF heart compensator simultaneously. It is a compromise between complete fixation of the heart, which damages the heart tissue, on one hand and complex and impractical compensation of the free heart movement on the other. One of the core components of the proposed system is the slave robot, which includes a 1 DOF compensator and a 4 DOF tool holder robot. Based on the selected laparoscopic tool, a modified agile-eye mechanism for activating the wrist was introduced,... 

    Disorders of the musculoskeletal system among Tehran, Iranian dentists

    , Article Journal of Musculoskeletal Pain ; Vol. 22, issue. 3 , 2014 , pp. 256-259 ; ISSN: 10582452 Shadmehr, A ; Haddad, O ; Azarnia, S ; Sanamlo, Z ; Sharif University of Technology
    Objectives: Although dental practitioners are confronted with a number of musculoskeletal disorders, relatively few studies have focused on this profession. The aim of this study was to investigate the prevalence of some musculoskeletal complaints of dentists in Iran. Methods: Four hundred and forty-six dentists in Tehran city, Iran were surveyed to determine the prevalence of musculoskeletal problems. We administrated a Persian-language version of the Nordic Questionnaire for this purpose. Results: Data gathered from Iranian dentists showed that most dentists [81%] reported pain in at least one joint. The most prevalent musculoskeletal disorders during the previous 12 months were reported... 

    Subject-specific and function-specific applicability of a hand-forearm musculoskeletal model

    , Article Biomedical Engineering - Applications, Basis and Communications ; Volume 27, Issue 6 , 2015 ; 10162372 (ISSN) Hosseininejad, S ; Farahmand, F ; Fateh, H. R ; Forogh, B ; Sharif University of Technology
    World Scientific Publishing Co. Pte Ltd  2015
    There is ambiguity on the quantitative validity of the predictions revealed by musculoskeletal models for muscle forces. This study investigated the consistency between the predictions of a musculoskeletal model of the upper limb and the experimental data for a number of different subjects and functional tasks. Six normal subjects performed isokinetic eccentric or isotonic concentric contraction tests of the wrist muscles in well controlled conditions, using a robotic apparatus, and the net joint torque and angular velocities, as well as the surface electromyograms (EMG) signals of the muscles, were recorded. The experiments were then simulated using a parametric musculoskeletal model of... 

    An improved algorithm for heart Rate tracking during physical exercise using simultaneous wrist-type photoplethysmographic (PPG) and acceleration signals

    , Article 2016 23rd Iranian Conference on Biomedical Engineering and 2016 1st International Iranian Conference on Biomedical Engineering, ICBME 2016, 23 November 2016 through 25 November 2016 ; 2017 , Pages 146-149 ; 9781509034529 (ISBN) Boloursaz Mashhadi, M ; Essalat, M ; Ahmadi, M ; Marvasti, F ; Sharif University of Technology
    Causal Heart Rate (HR) monitoring using photoplethysmographic (PPG) signals recorded from wrist during physical exercise is a challenging task because the PPG signals in this scenario are highly contaminated by artifacts caused by hand movements of the subject. This paper proposes a novel algorithm for this problem, which consists of two main blocks of Noise Suppression and Peak Selection. The Noise Suppression block removes Motion Artifacts (MAs) from the PPG signals utilizing simultaneously recorded 3D acceleration data. The Peak Selection block applies some decision mechanisms to correctly select the spectral peak corresponding to HR in PPG spectra. Experimental results on benchmark... 

    Experimental feasibility study of estimation of the normalized central blood pressure waveform from radial photoplethysmogram

    , Article Journal of Healthcare Engineering ; Volume 6, Issue 1 , 2015 , Pages 121-144 ; 20402295 (ISSN) Zahedi, E ; Sohani, V ; Mohd. Ali, M. A ; Chellappan, K ; Beng, G. K ; Sharif University of Technology
    Multi-Science Publishing Co. Ltd  2015
    The feasibility of a novel system to reliably estimate the normalized central blood pressure (CBPN) from the radial photoplethysmogram (PPG) is investigated. Right-wrist radial blood pressure and left-wrist PPG were simultaneously recorded in five different days. An industry-standard applanation tonometer was employed for recording radial blood pressure. The CBP waveform was amplitude-normalized to determine CBPN. A total of fifteen second-order autoregressive models with exogenous input were investigated using system identification techniques. Among these 15 models, the model producing the lowest coefficient of variation (CV) of the fitness during the five days was... 

    Improvement of upper limb motor control and function after competitive and noncompetitive volleyball exercises in chronic stroke survivors: a randomized clinical trial

    , Article Archives of Physical Medicine and Rehabilitation ; Volume 100, Issue 3 , 2019 , Pages 401-411 ; 00039993 (ISSN) Mandehgary Najafabadi, M ; Azad, A ; Mehdizadeh, H ; Behzadipour, S ; Fakhar, M ; Taghavi Azar Sharabiani, P ; Parnianpour, M ; Taghizadeh, G ; Khalaf, K ; Sharif University of Technology
    W.B. Saunders  2019
    Objectives: To investigate the effects of competitive and noncompetitive volleyball exercises on the functional performance and motor control of the upper limbs in chronic stroke survivors. Design: Randomized clinical trial. Setting: Outpatient rehabilitation center. Participants: Chronic stroke survivors (N=48). Interventions: Participants were randomly assigned to competitive (n=16) or noncompetitive (n=16) volleyball exercise groups (60min/d volleyball exercise+30min/d traditional rehabilitation, 3d/wk for 7wk) and control group (n=16). Main Outcome Measures: Reach and grasp motor control measures were evaluated through kinematic analysis. Functional outcomes were assessed via Motor... 

    An extended algorithm for autonomous grasping of soft tissues during robotic surgery

    , Article International Journal of Medical Robotics and Computer Assisted Surgery ; Volume 16, Issue 5 , 2020 , Pages 1-15 Amirkhani, G ; Farahmand, F ; Yazdian, S. M ; Mirbagheri, A ; Sharif University of Technology
    John Wiley and Sons Ltd  2020
    Background: Autonomous grasping of soft tissues can facilitate the robotic surgery procedures. The previous attempts for implementing auto-grasping have been based on a simplistic representation of the actual surgery maneuvers. Method: A generalized three-zone grasp model was introduced to consider the effect of the pull force angulation on the grasp mode, that is, damage, slip, or safe grasp. Also, an extended auto-grasping algorithm was proposed in which the trigger force is automatically controlled against the pull force magnitude and direction, to achieve a safe and secure grasp. Results: The autonomous grasping experiments against a varying pull force in a phantom study indicated a good...