scholarly journals WRIST REHABILITATION WITH MANIPULATOR TO PERFORM PASSIVE AND ACTIVE EXERCISES

2019 ◽  
Vol 49 (2) ◽  
pp. 52-57
Author(s):  
Piotr Kuryło ◽  
Joanna Cyganiuk ◽  
Peter Frankovský ◽  
Marianna Trebuňová

The paper characterizes basic dysfunctions and diseases of a human wrist as well as describes the mechanics and pathomorphology of the human hand. The radial-carpal joint was analyzed in terms of his ranges of motion. The results of the analysis, i.e. the number of degrees of freedom for a free hand, are included. The concept of manipulator construction for optimal rehabilitation of the wrist was developed. Expected effects of the exercises, which can be implemented on the designed manipulator, were also described. A comparative analysis of other appliances supporting the rehabilitation of the human upper limb were presented. The main purpose of the designed manipulator was to gain full control of implementation of exercises performed by the patient and to archive and precisely track the progress in the rehabilitation. An important feature of the designed manipulator is its versatility enabling its use for: exercises of both hands (left and right) with the repetitive movements, choose of exercises (active and passive movements), choose of the degree of disability of the patient.

2021 ◽  
Vol 11 (13) ◽  
pp. 5865
Author(s):  
Muhammad Ahsan Gull ◽  
Mikkel Thoegersen ◽  
Stefan Hein Bengtson ◽  
Mostafa Mohammadi ◽  
Lotte N. S. Andreasen Struijk ◽  
...  

Wheelchair mounted upper limb exoskeletons offer an alternative way to support disabled individuals in their activities of daily living (ADL). Key challenges in exoskeleton technology include innovative mechanical design and implementation of a control method that can assure a safe and comfortable interaction between the human upper limb and exoskeleton. In this article, we present a mechanical design of a four degrees of freedom (DOF) wheelchair mounted upper limb exoskeleton. The design takes advantage of non-backdrivable mechanism that can hold the output position without energy consumption and provide assistance to the completely paralyzed users. Moreover, a PD-based trajectory tracking control is implemented to enhance the performance of human exoskeleton system for two different tasks. Preliminary results are provided to show the effectiveness and reliability of using the proposed design for physically disabled people.


Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 137
Author(s):  
Larisa Dunai ◽  
Martin Novak ◽  
Carmen García Espert

The present paper describes the development of a prosthetic hand based on human hand anatomy. The hand phalanges are printed with 3D printing with Polylactic Acid material. One of the main contributions is the investigation on the prosthetic hand joins; the proposed design enables one to create personalized joins that provide the prosthetic hand a high level of movement by increasing the degrees of freedom of the fingers. Moreover, the driven wire tendons show a progressive grasping movement, being the friction of the tendons with the phalanges very low. Another important point is the use of force sensitive resistors (FSR) for simulating the hand touch pressure. These are used for the grasping stop simulating touch pressure of the fingers. Surface Electromyogram (EMG) sensors allow the user to control the prosthetic hand-grasping start. Their use may provide the prosthetic hand the possibility of the classification of the hand movements. The practical results included in the paper prove the importance of the soft joins for the object manipulation and to get adapted to the object surface. Finally, the force sensitive sensors allow the prosthesis to actuate more naturally by adding conditions and classifications to the Electromyogram sensor.


2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Matthew J. Dolan ◽  
Tomasz P. Dutka ◽  
Raymond R. Volkas

Abstract We analyse the experimental limits on the breaking scale of Pati-Salam extensions of the Standard Model. These arise from the experimental limits on rare-meson decay processes mediated at tree-level by the vector leptoquark in the model. This leptoquark ordinarily couples to both left- and right-handed SM fermions and therefore the meson decays do not experience a helicity suppression. We find that the current limits vary from $$ \mathcal{O} $$ O (80–2500) TeV depending on the choice of matrix structure appearing in the relevant three-generational charged-current interactions. We extensively analyse scenarios where additional fermionic degrees of freedom are introduced, transforming as complete Pati-Salam multiplets. These can lower the scales of Pati-Salam breaking through mass-mixing within the charged-lepton and down-quark sectors, leading to a helicity suppression of the meson decay widths which constrain Pati-Salam breaking. We find four multiplets with varying degrees of viability for this purpose: an SU(2)L/R bidoublet, a pair of SU(4) decuplets and either an SU(2)L or SU(2)R triplet all of which contain heavy exotic versions of the SM charged leptons. We find that the Pati-Salam limits can be as low as $$ \mathcal{O} $$ O (5–150) TeV with the addition of these four multiplets. We also identify an interesting possible connection between the smallness of the neutrino masses and a helicity suppression of the Pati-Salam limits for three of the four multiplets.


2011 ◽  
Vol 10 (3) ◽  
pp. 51-60
Author(s):  
Brahim Nini

This work deals with the virtual manipulation of a real object through its images. The results presented in this paper give a movie-based solution to the simulation process. We show how the simulation of infinite virtual views of a moving object can be reached using a finite number of object's taken images stored in an organized way. The basis of this solution is an analytical geometry-based method that links explicit applied user's actions, resulting in an object's views change, and images that match the best such views. This paper presents an overall solution for these three intertwined parts of the virtual manipulation that involves six degrees of freedom. Hence, a user is able to freely manipulate a virtual object in a scene in whatever manner s/he likes. In this case, the actions are transformed into rotations and/or translations which lead to some changes in object's appearance, both covered by two viewing features: zoom and/or rotations


Author(s):  
Biyyala Srijith

A Gesture Controlled Car is a robot that can be controlled with a simple human touch. The user only needs to wear a touch device where the sensor is installed. The sensor will record the movement of the hand in a certain direction that will lead to the movement of the robot in the right places. The robot and the touch device are connected wirelessly with radio waves. The user can communicate with the robot in a very friendly way due to wireless communication. We can control the car using accelerometer sensors that are connected to our hand glove. Sensors are designed to replace the remote control commonly used to drive a car. It will allow the user to control the forward, backward, left and right, while using the same accelerometer sensor to control the car's steering wheel. The movement of the car is controlled by the separation method. The machine involves rotating both front and rear wheels on the left or right side to move the non-clockwise side and another pair around the clock causing the car to rotate with its axis without going forward or backward. The main advantage of this machine is that the car with this method can take sharp turns without difficulty. The design and use of a robotic control arm using a flex sensor is suggested. The robot arm is designed to consist of four moving fingers, each with three connectors, an opposing thumb, a round wrist, and an elbow. The robot arm is designed to mimic the movements of a human hand using a hand glove.


Author(s):  
Thomas E. Pillsbury ◽  
Ryan M. Robinson ◽  
Norman M. Wereley

Pneumatic artificial muscles (PAMs) are used in robotics applications for their light-weight design and superior static performance. Additional PAM benefits are high specific work, high force density, simple design, and long fatigue life. Previous use of PAMs in robotics research has focused on using “large,” full-scale PAMs as actuators. Large PAMs work well for applications with large working volumes that require high force and torque outputs, such as robotic arms. However, in the case of a compact robotic hand, a large number of degrees of freedom are required. A human hand has 35 muscles, so for similar functionality, a robot hand needs a similar number of actuators that must fit in a small volume. Therefore, using full scale PAMs to actuate a robot hand requires a large volume which for robotics and prosthetics applications is not feasible, and smaller actuators, such as miniature PAMs, must be used. In order to develop a miniature PAM capable of producing the forces and contractions needed in a robotic hand, different braid and bladder material combinations were characterized to determine the load stroke profiles. Through this characterization, miniature PAMs were shown to have comparably high force density with the benefit of reduced actuator volume when compared to full scale PAMs. Testing also showed that braid-bladder interactions have an important effect at this scale, which cannot be modeled sufficiently using existing methods without resorting to a higher-order constitutive relationship. Due to the model inaccuracies and the limited selection of commercially available materials at this scale, custom molded bladders were created. PAMs created with these thin, soft bladders exhibited greatly improved performance.


Author(s):  
Nandhini Kesavan ◽  
Raajan N. R.

The main objective of gesture recognition is to promote the technology behind the automation of registered gesture with a fusion of multidimensional data in a versatile manner. To achieve this goal, computers should be able to visually recognize hand gestures from video input. However, vision-based hand tracking and gesture recognition is an extremely challenging problem due to the complexity of hand gestures, which are rich in diversities due to high degrees of freedom involved by the human hand. This would make the world a better place with for the commons not only to live in, but also to communicate with ease. This research work would serve as a pharos to researchers in the field of smart vision and would immensely help the society in a versatile manner.


2014 ◽  
Vol 5 (3) ◽  
pp. 25-48
Author(s):  
Girish Sriram ◽  
Alex Jensen ◽  
Steve C. Chiu

The human hand along with its fingers possess one of the highest numbers of nerve endings in the human body. It thus has the capacity for the richest tactile feedback for positioning capabilities. This article shares a new technique of controlling slippage. The sensing system used for the detection of slippage is a modified force sensing resistor (FSR®). The control system is a fuzzy logic control algorithm with multiple rules that is designed to be processed on a mobile handheld computing platform and integrated/working alongside a traditional Electromyography (EMG) or Electroencephalography (EEG) based control system used for determining position of the fingers. A 5 Degrees of Freedom (DOF) hand, was used to test the slippage control strategy in real time. First a reference EMG signal was used for getting the 5 DOF hand to grasp an object, using position control. Then a slip was introduced to see the slippage control strategy at work. The results based on the plain tactile sensory feedback and the modified sensory feedback are discussed.


Robotics ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 67
Author(s):  
Woo-hyeok Choi ◽  
Yukio Takeda

The thumb assists other fingers, and any damage in its functionality prevents the human hand from performing dexterous functions. In this paper, the kinematic design of the (2–RRU)–URR parallel mechanism as the application of the thumb rehabilitation device is proposed. This mechanism is an over-constrained mechanism capable of achieving the required mobility with fewer joints. Three degrees of freedom exist—two rotational and one translational mobility—that are related to each thumb movement: adduction–abduction and flexion–extension. Considering the narrow space of the hand, actuators are designed to divide its placement into the surface of the palm. To avoid the collisions between the device and the hand, an offset was adopted. The displacement analysis problem is solved by dividing it into two parts: the planar motion generator (PMG) and orientation generator (OG), according to each functional motion, and the corresponding equations and procedures are presented. To clarify the basic characteristics of this mechanism, the reachable workspace of the PMG and rotational ability and sensitivity of the OG is demonstrated numerically. Because a large input torque difference is dangerous in the rehabilitation mechanism, the effective workspace is determined according to the magnitude of the input torque differences and compared with the measured thumb movements.


Author(s):  
Esme Abbot ◽  
Amanda de Oliveira Barros ◽  
James Yang

Abstract Human hands play a key role in almost all activities of daily living (ADLs) because it is an incredibly versatile tool capable of complex motion. For individuals who have had a complete loss of the hand, the ability to perform ADLs is impaired. Effective prosthetics accurately simulate the movements of a human hand by providing a high number of degrees of freedom, an efficient control system, and an anthropomorphic appearance. In this paper, the design and construction process of a highly anthropomorphic soft robotic prosthetic hand is outlined. The design specifications of the hand are based on feedback from current and former prosthetic users. The hand endoskeleton was 3D printed using fused deposition modeling techniques and was enclosed in a silicone coating modeled, after a real human hand. The hand presents anthropomorphic design in its realistic bone shapes and in its external covering that is like skin in texture and mechanical properties. The hand utilizes the flexibility of silicone instead of antagonistic tendons which would otherwise add complexity and weight to the prosthetic design. The prototype also includes adduction/abduction of the fingers, which is a common omitted movement in other prosthetics. Testing showed that the hand is capable of effective power and precision grasping.


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