Flexibility in Upper Limb Rehabilitation With the Use of 1-DOF Fourbar Linkages

In robotic rehabilitation the interaction is usually implemented by means of robots based on multi-Degree of Freedom (DOF) open kinematic chains. Despite their inherent flexibility these machines are expensive, complex and require routine maintenance and IT support. In contrast, mechanisms based on closed kinematic chains and especially 1-DOF four- and six bar linkages are simple, yet capable of generating paths with complex kinematic characteristics. These mechanisms are preferable when simplicity and cost are the major criteria, for example in the case of community-based rehabilitation in developing countries. On the other hand, rehabilitation using 1-DOF limits flexibility and potentially impairs the exercise effectiveness, since the patient does not have access to a variety of kinematic challenges. Nevertheless, by careful ergonomic design and by considering varying time constraints, link rotation ranges and varying link lengths this limitation can be overcome. This work aims to demonstrate the potential of 1-DOF four-bar linkages to provide flexibility in therapy by considering a Hoeken’s straight line four-bar linkage. After the mechanism is dimensioned, a previously developed method is employed for establishing a final prototype design which accounts for significant neurophysiological models such as Minimum Jerk Model, Fitts’s Law and Just Noticeable Differences. Given the mechanism characteristics, its potential for generation of exercises that vary with respect to temporal and spatial characteristics is demonstrated.

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Sensor-based technology for upper limb rehabilitation in patients with multiple sclerosis: A randomized controlled trial

Restorative Neurology and Neuroscience ◽

10.3233/rnn-201033 ◽

2020 ◽

Vol 38 (4) ◽

pp. 333-341

Author(s):

Marco Tramontano ◽

Giovanni Morone ◽

Sara De Angelis ◽

Laura Casagrande Conti ◽

Giovanni Galeoto ◽

...

Keyword(s):

Multiple Sclerosis ◽

Upper Limb ◽

Controlled Trial ◽

Control Group ◽

Hand Rehabilitation ◽

Upper Limb Rehabilitation ◽

Rehabilitation Programs ◽

Scale Scores ◽

Limb Rehabilitation ◽

Experimental Group

Background: Sensor-based technological therapy devices may be good candidates for neuromotor rehabilitation of people with Multiple Sclerosis (MS), especially for treating upper extremities function limitations. The sensor-based device rehabilitation is characterized by interactive therapy games with audio-visual feedback that allows training the movement of shoulders, elbows, and wrist, measuring the strength and the active range of motion of upper limb, registering data in an electronic database to quantitatively monitoring measures and therapy progress. Objective: This study aimed to investigate the effects of sensor-based motor rehabilitation in add-on to the conventional neurorehabilitation, on increasing the upper limb functions of patients with MS. Methods: Thirty patients were enrolled in the study and randomly assigned to the experimental group and the control group. The training consisting of twelve sessions of upper limb training was compared with twelve sessions of upper limb sensory-motor training, without robotic support. Both rehabilitation programs were performed for 40 minutes three times a week, for 4 weeks, in addition to conventional therapy. All patients were evaluated at the baseline (T0) and after 4 weeks of training (T1). Results: The within-subject analysis showed a statistically significant improvement in both groups, in the Modified Barthel Index and in the Rivermead Mobility Index scores and a significant improvement in Multiple Sclerosis Quality of Life-54 in the experimental. The analysis of effectiveness revealed that, compared with baseline (T0), the improvement percentage in all clinical scale scores was greater in the experimental group than the control group. Conclusions: Proposed training provides an intensive and functional-oriented rehabilitation that objectively evaluates achieved progress through exercises. Therefore, it can represent a good complementary strategy for hand rehabilitation in MS patients.

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Synthesis and Analysis of a Chebyschev’s Straight Line Four-Bar Linkage for Generating a Minimum Jerk Velocity Profile

Volume 5A: 38th Mechanisms and Robotics Conference ◽

10.1115/detc2014-35510 ◽

2014 ◽

Cited By ~ 2

Author(s):

Evagoras G. Xydas

Keyword(s):

Velocity Profile ◽

Kinematic Chain ◽

Mechanical Constraints ◽

Minimum Jerk ◽

Straight Line ◽

Wide Range ◽

Spatio Temporal ◽

Line Trajectory ◽

Four Bar Linkage ◽

Input Torque

The interaction between human and passive, constraint-based path generating mechanisms has been scarcely studied. When it comes to rehabilitation robots, output trajectories and/or forces are achieved mainly as a result of actuation on all joints, since they form an open kinematic chain. On the other end, there exists a wide range of mechanisms that can trace complex trajectories primarily due to mechanical constraints in their topology and structure. Probably the simplest example is the four bar linkage, a widely used 1-DOF mechanism. It consists of a driving link, a driven link, and a coupler which connects the two. As the input link rotates, each point on the coupler link traces a unique trajectory in space, called a coupler curve. Ideally, the linkage dimensions can be chosen so that a near-natural hand trajectory is generated for a specific task. As a first step, in this work a straight line generating four-bar mechanism, namely the Chebyshev’s linkage is considered for generating a natural bell-shaped velocity profile, as prescribed by the Minimum-Jerk-Model. Initially the mechanism is synthesized for producing a straight line trajectory of a desired length. Kinematic and kinetostatic analysis is performed in order to determine the required input torque necessary for achieving the desired spatio-temporal profile. The main objective is to determine whether this input torque can approximated by a series of linear torsional springs that can be installed on the pivoted side of the input link.

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Design and Development of Fun Lean Augmented and Virtual Reality Prototypes for Hand and Upper Limb Rehabilitation

Knowledge Innovation Through Intelligent Software Methodologies, Tools and Techniques - Frontiers in Artificial Intelligence and Applications ◽

10.3233/faia200569 ◽

2020 ◽

Author(s):

Chien-Sing Lee ◽

Pei-Yee Tan ◽

Hong-Wei Wong

Keyword(s):

Virtual Reality ◽

Augmented Reality ◽

Occupational Therapy ◽

Activity Level ◽

Leap Motion ◽

Hand Rehabilitation ◽

Cognitive Health ◽

Upper Limb Rehabilitation ◽

Limb Rehabilitation ◽

Rehabilitation Exercise

Lack of motivation to carry out rehabilitation exercise from a hand injury or stroke is one of the most challenging aspects faced by Occupational Therapy (OT) and Certified Occupational Therapy Assistants (COTA). Some patients refuse to exercise due to behavioral, psychological, or cognitive reasons. We hypothesize that recovery to their former activity level and strength can be quickened if we develop Augmented Reality (AR)/Virtual Reality (VR) games which add fun into rehabilitative hand exercises. A physical card game for hand rehabilitation, which contains puzzle pieces and rehabilitative exercise instructions, is designed and developed to trigger the display of an Augmented Reality virtual reward upon completion of the puzzle. User testing results are promising. Users find it easy to use, supportive, efficient, exciting and interesting; suitable for either individual or collaborative play. Being object-oriented, it is also scalable, extensible and easily portable. An extended Leap-Motion-enhanced AR environment for limb rehabilitation is being developed. We hope that both will improve physical, mental and socio-cognitive health.

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Haptic-Enabled Hand Rehabilitation in Stroke Patients: A Scoping Review

Applied Sciences ◽

10.3390/app11083712 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3712

Author(s):

Mohamed-Amine Choukou ◽

Sophia Mbabaali ◽

Jasem Bani Hani ◽

Carol Cooke

Keyword(s):

Scoping Review ◽

Research Question ◽

Therapeutic Approaches ◽

Hand Rehabilitation ◽

Hand Therapy ◽

Upper Limb Rehabilitation ◽

Effective Interventions ◽

Study Selection ◽

Multifaceted Interventions ◽

Limb Rehabilitation

There is a plethora of technology-assisted interventions for hand therapy, however, less is known about the effectiveness of these interventions. This scoping review aims to explore studies about technology-assisted interventions targeting hand rehabilitation to identify the most effective interventions. It is expected that multifaceted interventions targeting hand rehabilitation are more efficient therapeutic approaches than mono-interventions. The scoping review will aim to map the existing haptic-enabled interventions for upper limb rehabilitation and investigates their effects on motor and functional recovery in patients with stroke. The methodology used in this review is based on the Arksey and O’Malley framework, which includes the following stages: identifying the research question, identifying relevant studies, study selection, charting the data, and collating, summarizing, and reporting the results. Results show that using three or four different technologies was more positive than using two technologies (one technology + haptics). In particular, when standardized as a percentage of outcomes, the combination of three technologies showed better results than the combination of haptics with one technology or with three other technologies. To conclude, this study portrayed haptic-enabled rehabilitation approaches that could help therapists decide which technology-enabled hand therapy approach is best suited to their needs. Those seeking to undertake research and development anticipate further opportunities to develop haptic-enabled hand telerehabilitation platforms.

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Dynamic Performance Analysis of Minimally Actuated 4-Bar Linkages for Upper Limb Rehabilitation

Volume 5A: 39th Mechanisms and Robotics Conference ◽

10.1115/detc2015-46828 ◽

2015 ◽

Cited By ~ 2

Author(s):

Evagoras G. Xydas ◽

Andreas Mueller

Keyword(s):

Velocity Profile ◽

Dynamic Performance ◽

Computer Control ◽

Human Robot Interaction ◽

Upper Limb Rehabilitation ◽

Kinematic Chains ◽

Hand Motion ◽

Straight Line ◽

Non Linear ◽

Dynamic Performance Analysis

In the last two decades robotic rehabilitation research provided insight regarding the human-robot interaction, helped understand the process by which the impaired nervous system is retrained to better control the hand motion, and led to the development of a number of mathematical and neurophysiological models that describe both the hand motion and the robot control. Now that this pool of knowledge is available, the respective models can be applied in a number of ways outside the robot domain, in which, machines are based on open kinematic chains with n-degrees of freedom (DOF’s) and sophisticated computer control, actuation and sensing. One such example is the use of mechanisms, closed kinematic chains which can still generate complex — yet specific — trajectories with fewer DOF’s. This paper further extends previous work on the design of such passive-active mechanisms that replicate the natural hand motion along a straight-line. The natural hand motion is described by a smooth bell-shaped velocity profile which in turn is generated by the well-established Minimum-Jerk-Model (MJM). Three different straight line 4-bar linkages, a Chebyshev’s, a Hoeken’s and a Watt’s, are examined. First, with the use of kinetostatic analysis and given the natural hand velocity and acceleration, the torque function of non-linear springs that act on the driving link is deduced. Then, given that the springs are acting, interaction with impaired users is considered and the extra actuation power that can maintain the natural velocity profile is calculated. A multibody dynamics software is employed for further assessing the mechanisms’ dynamic response under varying interaction forces. Also, different parameters like inertia are altered and the effects on internal (springs) and external (actuator) power are examined. Then, the three mechanisms are compared with respect to size, required amount of external power, ergonomic issues etc. Finally, it is investigated whether a linear fit of the non-linear spring torque can be adequate for generating the desired MJM trajectory and operate effectively in collaboration with the active part of the control.

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Analysis and Passive Control of a Four-Bar Linkage for the Rehabilitation of Upper-Limb Motion

Volume 3: Multiagent Network Systems; Natural Gas and Heat Exchangers; Path Planning and Motion Control; Powertrain Systems; Rehab Robotics; Robot Manipulators; Rollover Prevention (AVS); Sensors and Actuators; Time Delay Systems; Tracking Control Systems; Uncertain Systems and Robustness; Unmanned, Ground and Surface Robotics; Vehicle Dynamics Control; Vibration and Control of Smart Structures/Mech Systems; Vibration Issues in Mechanical Systems ◽

10.1115/dscc2015-9916 ◽

2015 ◽

Cited By ~ 1

Author(s):

Evagoras G. Xydas ◽

Loucas S. Louca ◽

Andreas Mueller

Keyword(s):

Upper Limb ◽

Passive Control ◽

Human Motion ◽

Human Robot Interaction ◽

Robotic Rehabilitation ◽

Kinematic Chains ◽

Natural Motion ◽

Reaching Tasks ◽

Straight Line ◽

Four Bar Linkage

In the last two decades robotic rehabilitation research provided significant insight regarding the human-robot interaction, helped understand the process by which the impaired nervous system is retrained to better control movements, and led to the development of a number of mathematical and neurophysiological models that describe both the human motion and the robot control. The human-machine interaction in this research is typically achieved through robotic devices that are based on open kinematic chains. These devices have multiple degrees of freedom (DOF), sophisticated computer control, actuation and sensing. The flexibility of such approach enables the easy implementation of the various models and methods that have to be applied in order to maximize the potential of robotic rehabilitation. On the other hand, mechanisms with fewer DOF’s that are based on closed kinematic chains can generate specific, yet adequate trajectories for the purposes of robotic rehabilitation. An example of such mechanisms is four-bar linkages that have only 1-DOF but yet can generate paths with complex kinematic characteristics. Design and analysis of four-bar linkages is used to achieve a variety of kinematics in terms of trajectory, velocity and acceleration profiles. The simplicity of these mechanisms is appealing and they can be used in rehabilitation due to their ability to replicate the motion of various human joints and limbs. The focus of the current work is to study the use of a four-bar linkage for generating the natural motion of upper-limb reaching tasks with the intention of using this mechanism for rehabilitation. This natural hand motion is described by a straight-line trajectory with a smooth bellshaped velocity profile, which in turn is generated by the well-established Minimum Jerk Model (MJM). The goal is to design passive control elements in a four-bar linkage that generate the required torque for producing the MJM motion. The passive elements are two linear translational springs that act on the driving link of a straight line generating mechanism. A design optimization is used to minimize the difference between the desired and actual input spring torque while remaining within the predefined design space. The final arrangement is simulated in a Multibody Dynamics software that applies feed-forward dynamics to generate the mechanism’s free response to the torque generated by the designed linear springs. The results of this work suggest that systematic design of a four-bar linkage can lead to simple mechanisms that can replicate the natural motion of reaching tasks. Relatively inexpensive linear springs can be employed in the design of passive-active controlled therapeutic mechanisms. Further investigation that combines analysis of both active and passive control/actuation elements must be performed for finalizing the control design. Simulations and analysis that incorporate various impaired hand responses must be also performed in order to finalize the design.

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