Posts Tagged Performance evaluation

[ARTICLE] Portable Motion-Analysis Device for Upper-Limb Research, Assessment, and Rehabilitation in Non-Laboratory Settings – Full Text


This study presents the design and feasibility testing of an interactive portable motion-analysis device for the assessment of upper-limb motor functions in clinical and home settings. The device engages subjects to perform tasks that imitate activities of daily living, e.g. drinking from a cup and moving other complex objects. Sitting at a magnetic table subjects hold a 3D printed cup with an adjustable magnet and move this cup on the table to targets that can be drawn on the table surface. A ball rolling inside the cup can enhance the task challenge by introducing additional dynamics. A single video camera with a portable computer tracks real-time kinematics of the cup and the rolling ball using a custom-developed, color-based computer-vision algorithm. Preliminary verification with marker-based 3D-motion capture demonstrated that the device produces accurate kinematic measurements. Based on the real-time 2D cup coordinates, audio-visual feedback about performance can be delivered to increase motivation. The feasibility of using this device in clinical diagnostics is demonstrated on 2 neurotypical children and also 3 children with upper-extremity impairments in the hospital, where conventional motion-analysis systems are difficult to use. The device meets key needs for clinical practice: 1) a portable solution for quantitative motor assessment for upper-limb movement disorders at non-laboratory clinical settings, 2) a low-cost rehabilitation device that can increase the volume of in-home physical therapy, and 3) the device affords testing and training a variety of motor tasks inspired by daily challenges to enhance self-confidence to participate in day-to-day activities.



An integral part of clinical care for individuals with motor disorders is to assess motor function to guide and evaluate medical treatment, surgical intervention or physical therapy. One of the challenges for assessing motor function is to define sensitive and quantitative measures that can be readily obtained in clinical practice. The objective of this study was to develop a device that affords quantitative assessment of motor impairments in non-laboratory settings. The specific focus is on individuals with upper-limb movement disorders. One central goal was to ground the task in scientific research to relate clinical measures to research and capitalize on insights from fundamental research.

This paper first lays out the need for such a device particularly for children with motor disorders and post-stroke rehabilitation. We then motivate the specific motor task that was originally conceived for basic research on motor control. We then detail the design of the prototype with all hardware and software components so that it can be replicated. One design goal was to make the device low-cost, so that it can be used in many clinical environments including at home for therapeutic exercises. We conclude with first results from pilot experiments acquired both in a traditional laboratory setting and in an Epilepsy Monitoring Unit. These first data were obtained from children with dystonia. However, the device is not limited to this population and is currently further modified for the assessment of stroke patients.

A. Clinical Assessments of Motor Disorders

A motor disorder manifests as an impaired ability to execute a movement with the intended spatial and temporal pattern. This includes abnormal posturing, presence of unintended excessive movement, and normal movements occurring at unintended or inappropriate times [1]. Patients with upper-limb impairments require special assistance to perform common motor tasks associated with self-care, such as feeding and dressing. Challenges in their movement control result in frustration, which leads to less engagement and practice, and thereby fewer opportunities to attenuate their motor disabilities and improve their movement control.

Motor disorder are observed also among children. Cerebral Palsy (CP) is a common cause of movement disorders among children, affecting 3 to 4 individuals per 1000 births in the US. The dyskinetic form of CP occurs in 15% of all cases [2]. Due to inflexible postures, caused by muscle spasms and contractures together with involuntary jerky movements, children with dyskinetic CP are often prevented from participation in many daily activities. This also prevents them from acquiring age-appropriate motor skills during critical periods of skill development [3], [4]. This is particularly aggravated when the condition affects the upper limbs.

For clinical motor assessments, the current standard tools are clinical scales. For cerebral palsy, typical tests are the gross motor function classification system (GMFCS) [5], the manual ability classification system (MACS) [6], the House Scale [7], the Melbourne Assessment [8], the Assisting Hand Assessment [9], the Hypertonia Assessment Tool (HAT) [10], the Barry-Albright Dystonia (BAD) scale [11], and the Shriners Hospital for Children Upper Extremity Evaluation [12]. These outcome measures were devised to satisfy the typical criteria for effective outcome measures, including reliability, validity, specificity, and responsiveness [13]. Although useful, these rating scales rely on subjective assessment and questionnaires that are vulnerable to inter-rater and test-retest reliability, nonlinearity, multi-dimensionality, and ceiling or floor effects [14]. These shortcomings need to be overcome by more quantitative outcome measures to provide a better evaluation of the individual’s motor functions and abilities, and potentially utilize such measures to objectvely assess and titrate interventions.

B. Quantitative Assessment of Motor Function

Motion tracking technologies have provided quantitative means of recording movements through a variety of sensing technology that tracks and stores movement. Camera-based motion capture, such as Vicon (Vicon Motion Systems, Oxford, UK) and Optitrak (Northern Digital Inc, Ontario, CA) requires external markers or sensors placed on key anatomical landmarks to reconstruct the skeletal model of human body parts. These state-of-the-art technologies track motion to very high precision with high sampling rates and they have been used for pre- and post-treatment assessment of upper- or lower-extremity pathologies. However, such data acquisition is limited to traditional laboratory settings because the multi-camera systems are expensive and not portable.

On the other hand, there are low-cost inertial measurement units (IMUs) that directly measure acceleration, rotational change and magnetic orientation. While these sensors have the advantage that they are self-contained and wearable, drawbacks are degraded accuracy due to drift, calibration errors and noise inherent to inertial sensors and the need to frequently recharge batteries for real-time data streaming [15]. Moreover, attaching sensors to body parts can be inconvenient or even impossible for certain clinical populations, and many children will not tolerate them.

In view of the above arguments, there is a strong need for less invasive devices that can provide quantitative measurements in tasks related to upper-extremeity motor function. Preferably, such a device should allow for portability and be low-cost to reach large populations.

C. Low-Cost Rehabilitation at Home

Rehabilitation follows standard practice and frequently requires one-on-one interaction with a therapist for extended periods of time. For these reasons, robotic devices have emerged to deliver higher-dosage and higher-intensity training for patients with movement disorders such as cerebral palsy and stroke [16]–[17][18][19]. However, while effective, robotic therapy is expensive and to date can only be used in clinical settings. To increase the volume in therapy, lower-cost devices that can be used at home are urgently needed.

Performance improvements with predominant home training are indeed possible. This was demonstrated by pediatric constraint-induced movement therapy (CIMT) for children with hemiparetic CP [20], [21]. Further, it was shown that even children with severe dystonia can improve their performance if they use an interface or device that enables and facilitates their severely handicapped movements [22].

A portable low-cost device for home use that is able to provide reliable quantitative measurements would help address the above shortcomings. Measurements could also be streamed to careproviders on a secure cloud protocol, for diagnosis of interventions, analysis of therapeutic outcomes, and further follow up.

D. Theoretically-Grounded Rehabilitation

Motor tasks for home therapy should be engaging to avoid boredom and attrition and should also have functional relevance. With this goal in mind, we developed a motor task that was motivated by the daily self-feeding activity of leading a cup of coffee or a spoon filled with soup to the mouth. The core challenge of actions of this kind is that moving such an object with sloshing liquid presents complex interaction forces: any force applied to the cup also applies a force to the liquid that then acts back on the hand. When such internal dynamics is present, interaction forces become quite complex, and the human performing the task needs to predict and preempt the internal dynamics of the moving liquid. Clearly, better understanding task is like guiding a cup of coffee to one’s mouth or a spoonful of soup has high functional relevance. While many such functional tasks have been developed for rehabiltation (e.g., the box-and-block and the pegboard task), the quantitative assessment should allow for more than descriptive outcome measures such as error or success rate. Monitoring the ‘process’ continuously should provide more detailed insight into coordinative challenges. This is indeed possible in the task of guiding a cup of coffee as we explain next.

In previous research, we abstracted a relevant, yet simplified model task, inspired by guiding a cup of coffee [23]–[24][25][26]. To reduce the complexity and afford theoretical analyses, the “cup of coffee” was simplified to a rigid object with a rolling ball inside. The rolling ball represents the moving liquid; this is also similar to the children’s game of transporting an egg in a spoon [27]. Fig.1A-C shows the transition from the real object to the simplified physical model. Importantly, the original task (Fig.1A) was reduced to a two-dimensional model, where the subject interacts with the object via a robotic manipulandum. The virtual model consists of a cart with a suspended pendulum, a well-known benchmark problem in control theory.

FIGURE 1.Model for the task of carrying a cup of coffee. A: The real object. B: The simplified physical model. C: The equivalent cart-and pendulum model implemented in the virtual task.


Continue —->  Portable Motion-Analysis Device for Upper-Limb Research, Assessment, and Rehabilitation in Non-Laboratory Settings – IEEE Journals & Magazine

, , , , , , , , , , , , , , ,

Leave a comment

[Abstract + References] Self-paced movement intention recognition from EEG signals during upper limb robot-assisted rehabilitation


Currently, one of the challenges in EEG-based brain-computer interfaces (BCI) for neurorehabilitation is the recognition of the intention to perform different movements from same limb. This would allow finer control of neurorehabilitation and motor recovery devices by end-users [1]. To address this issue, we assess the feasibility of recognizing two self-paced movement intentions of the right upper limb plus a rest state from EEG signals recorded during robot-assisted rehabilitation therapy. In addition, the work proposes the use of Multi-CSP features and deep learning classifiers to recognize movement intentions of the same limb. The results showed performance peaked greater at (80%) using a novel classification models implemented in a multiclass classification scenario. On the basis of these results, the decoding of the movement intention could potentially be used to develop more natural and intuitive robot assisted neurorehabilitation therapies
1. S. R. Soekadar , N. Birbaumer , M. W. Slutzky , and L. G. Cohen , “Brain machine interfaces in neurorehabilitation of stroke,” Neurobiology of Disease, vol. 83, pp. 172-179, 2015.

2. P. Ofner , A. Schwarz , J. Pereira , and G. R. Müller-Putz , “Upper limb movements can be decoded from the time-domain of low-frequency EEG,” PLoS One, vol. 12, no. 8, p. e0182578, Aug 2017, poNE-D- 17-04785[PII].

3. F. Shiman , E. Lopez-Larraz , A. Sarasola-Sanz , N. Irastorza-Landa , M. Spler , N. Birbaumer , and A. Ramos-Murguialday , “Classification of different reaching movements from the same limb using EEG,” Journal of Neural Engineering, vol. 14, no. 4, p. 046018, 2017.

4. J. Pereira , A. I. Sburlea , and G. R. Müller-Putz , “EEG patterns of self- paced movement imaginations towards externally-cued and internally- selected targets,” Scientific Reports, vol. 8, no. 1, p. 13394, 2018.

5. R. Vega , T. Sajed , K. W. Mathewson , K. Khare , P. M. Pilarski , R. Greiner , G. Sanchez-Ante , and J. M. Antelis , “Assessment of feature selection and classification methods for recognizing motor imagery tasks from electroencephalographic signals,” Artif. Intell. Research, vol. 6, no. 1, p. 37, 2017.

6. I. Figueroa-Garcia et al , “Platform for the study of virtual task- oriented motion and its evaluation by EEG and EMG biopotentials,” in 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Aug 2014, pp. 1174–1177.

7. B. Graimann and G. Pfurtscheller , “Quantification and visualization of event-related changes in oscillatory brain activity in the timefrequency domain,” in Event-Related Dynamics of Brain Oscillations, ser. Progress in Brain Research, C. Neuper and W. Klimesch , Eds. Elsevier, 2006, vol. 159, pp. 79 – 97.

8. G. Pfurtscheller and F. L. da Silva , “Event-related EEG/MEG synchronization and desynchronization: basic principles,” Clinical Neurophysiology, vol. 110, no. 11, pp. 1842 – 1857, 1999.

9. G. Dornhege , B. Blankertz , G. Curio , and K. Muller , “Boosting bit rates in noninvasive EEG single-trial classifications by feature combination and multiclass paradigms,” IEEE Transactions on Biomedical Engineering, vol. 51, no. 6, pp. 993–1002, 2004.

10. X. Yong and C. Menon , “EEG classification of different imaginary movements within the same limb,” PLOS ONE, vol. 10, no. 4, pp. 1–24, 04 2015.

11. L. G. Hernandez , O. M. Mozos , J. M. Ferrandez , and J. M. Antelis , “EEG-based detection of braking intention under different car driving conditions,” Frontiers in Neuroinformatics, vol. 12, p. 29, 2018. [Online]. Available:

12. L. G. Hernandez and J. M. Antelis , “A comparison of deep neural network algorithms for recognition of EEG motor imagery signals,” in Pattern Recognition, 2018, pp. 126–134.

13. M. Abadi et al , “TensorFlow: Large-scale machine learning on heterogeneous systems,” 2015, software available from [Online]. Available:

via Self-paced movement intention recognition from EEG signals during upper limb robot-assisted rehabilitation – IEEE Conference Publication

, , , , , , , , , , , ,

Leave a comment

[Abstract] Towards Bilateral Upper-Limb Rehabilitation after Stroke using Kinect Game – IEEE Conference Publication


This paper presented a game-based rehabilitation of the upper limb after stroke. We designed and developed a game for supporting stroke patients to have an exercise their arms, and the game had functions for recording their playing and showing a performance report. The performance report can infer the progress of bilateral uppper-limb rehabilitation and use for comparing among patient cases. This is because the game used a Kinect device to detect the arm movements in aspect of precision and speed.


1. L. Anderson, G. A. Sharp, R. J. Norton, H. Dalal, S. G. Dean, K. Jolly, A. Cowie, A. Zawada, R. S. Taylor, “Home-based versus centre-based cardiac rehabilitation”, The Cochrane Library, 2017.

2. K. Thomson, A. Pollock, C. Bugge, M. C. Brady, “Commercial gaming devices for stroke upper limb rehabilitation: a survey of current practice”, Disability and Rehabilitation: Assistive Technology, vol. 11, no. 6, pp. 454-461, 2016.

3. L. Y. Joo, T. S. Yin, D. Xu, E. Thia, P. F. Chia, C. W. K. Kuah, K. K. He, “A feasibility study using interactive commercial off-the-shelf computer gaming in upper limb rehabilitation in patients after stroke”, Journal of rehabilitation medicine, vol. 42, no. 5, pp. 437-441, 2010.

4. K. Price, “Health promotion and some implications of consumer choice”, Journal of nursing management, vol. 14, no. 6, pp. 494-501, 2006.

5. J. A. M. Bravo, P. Paliyawan, T. Harada, R. Thawonmas, “Intelligent assistant for providing instructions and recommending motions during full-body motion gaming”, Consumer Electronics (GCCE) 2017 IEEE 6th Global Conference on. IEEE, pp. 1-2, 2017.


via Towards Bilateral Upper-Limb Rehabilitation after Stroke using Kinect Game – IEEE Conference Publication


, , , , , , , , , , ,

Leave a comment

[Abstract + References] Patient Evaluation of an Upper-Limb Rehabilitation Robotic Device for Home Use – IEEE Conference Publication


The paper presents a user study to compare the performance of two rehabilitation robotic systems, called HomeRehab and PupArm. The first one is a novel tele-rehabilitation system for delivering therapy to stroke patients at home and the second one has been designed and developed to provide rehabilitation therapy to patients in clinical settings. Nine patients with different neurological disorders participated in the study. The patients performed 16 movements with each robotic platform and after that they filled a usability survey. Moreover, to evaluate the patient’s performance with each robotic device, 8 movement parameters were computed from each trial and for the two robotic devices. Based on the analysis of subjective assessments of usability and the data acquired objectively by the robotic devices, we can conclude that the performance and user experience with both systems are very similar. This finding will be the base of more extensive studies to demonstrate that home-therapy with HomeRehab could be as efficient as therapy in clinical settings assisted by PupArm robot.


1. WHO global report. Preventing Chronic Diseases: A Vital Investment, World Health Organization, 2005.

2. J. Mackay, G. A. Mensah, The Atlas of Heart Disease and Stroke, Geneva, Switzerland:World Health Organization, 2004.

3. D. S. Nichols-Larsen, P. C. Clark, A. Zeringue, A. Greenspan, S. Blanton, “Factors Influencing Stroke Survivors Quality of Life during Subacute Recovery”, Stroke, vol. 36, pp. 14801484, 2005.

4. P. Langhorne, F. Coupar, A. Pollock, “Motor Recovery after Stroke: a Systematic Review”, The Lancet Neurology, vol. 8, no. 8, pp. 741754, 2009.

5. C. R. Carnigan, H. I. Krebs, “Telerehabilitation Robotics: Bright Lights Big Future?”, Journal of Rehabilitation Research and Development, vol. 43, no. 5, pp. 695-710, 2006.

6. K. J. Ottenbacher, P. M. Smith, S. B. Illig, R. T. Linn, G. V. Ostir, C. V. Granger, “Trends in Length of Stay Living Setting Functional Outcome and Mortality following Medical Reha-bilitation”, JAMA, vol. 292, no. 14, pp. 1687-1695, 2004.

7. L. Richards, C. Hanson, M. Wellborn, A. Sethi, “Driving Motor Recovery after Stroke”, Topics in Stroke Rehabilitation, vol. 15, no. 5, pp. 397411, 2008.

8. S. M. Linder, A. B. Rosenfeldt, A. Reiss, S. Buchanan, K. Sahu, C. R. Bay, S. L. Wolf, J. L. Alberts, “The Home Stroke Rehabilitation and Monitoring System Trial: A Randomized Controlled Trial”, International Journal of Stroke, vol. 8, no. 1, pp. 1747-4949, 2013.

9. T. Larsen, T. S. Olsen, J. Sorensen, “Early Home-Supported Discharge of Stroke Patients: A Health Technology Assessment”, International Journal of Technology Assessment in Health Care, vol. 22, no. 3, pp. 313-320, 2006.

10. Ifiaki Díaz, José María Catalan, Francisco Javier Badesa, Xabier Justo, Luis Daniel Lledo, Axier Ugartemendia, Jorge juan Gil, Jorge Díez, Nicolás García-Aracil, Development of a robotic device for post-stroke home tele-rehabilitation. Advances in Mechanical Engineering, vol. 10, no. 1, pp. 1-8, 2018.

11. J. Brooke, P. W. Jordan, B. Thomas, B. A. Weerd-meester, J. L. McClealland, “SUS: A quick and dirty usability scale” in Usability Evaluation in Industry, London:Taylor and Francis, pp. 189194, 1996.

12. R. Likert, G. M. Maranell, “A method of constructing an attitude scale” in Scaling: A Sourcebook for Behavioral Scientists, Chicago, IL:Aldine Publishing, pp. 233243, 1974.

13. H. J. Krebs, N. Hogan, M. L. Aisen, B. T. Volpe, “Robot-aided neurorehabilitation”, IEEE Transactions on Rehabilitation Engineering, vol. 6, no. 1, pp. 75-87, Mar 1998.

14. Franciso J Badesa, Ana Llinares, Ricardo Morales, Nicolas Garcia-Aracil, Jose M Sabater, Carlos Perez-Vidal, “Pneumatic planar rehabilitation robot for post-stroke patients”, Biomedical Engineering: Applications Basis and Communications, vol. 26, no. 2, pp. 1450025, 2014.

15. D. Lledo Luis, A. Diez Jorge, Bertomeu-Motos Arturo, Ezquerro Santiago, J. Badesa Francisco, M. Sabater-Navarro Jose, Garca-Aracil Nicolas, “A Comparative Analysis of 2D and 3D Tasks for Virtual Reality Therapies Based on Robotic-Assisted Neurorehabilitation for Post-stroke Patients”, Frontiers in Aging Neuroscience, vol. 8, pp. 205, 2016.

16. A. Llinares, F. J. Badesa, R. Morales, N. Garcia-Aracil, J. Sabater, E. Fernandez, “Robotic assessment of the influence of age on upper-limb sensorimotor function”, Clin. Interv. Aging, vol. 8, pp. 879, 2013.

17. D. S. Dunn, Statistics and data analysis for the behavioral sciences, New York, NY, US:McGraw-Hill, 2001.

18. J. Brooke, P. W. Jordan, B. Thomas, B. A. Weerd-meester, I. L. McClealland, “SUS: A quick and dirty usability scale” in Usability Evaluation in Industry, London:Taylor and Francis, pp. 189194, 1996.

19. AM Coderre, AA Zeid, SP Dukelow et al., “Assessment of upper-limb sensorimotor function of subacute stroke patients using visually guided reaching”, Neurorehabil Neural Repair., vol. 24, no. 6, pp. 528541, 2010.

via Patient Evaluation of an Upper-Limb Rehabilitation Robotic Device for Home Use – IEEE Conference Publication

, , , , , , , , , , ,

Leave a comment

[Abstract] Electromyography Based Orthotic Arm and Finger Rehabilitation System


Electromyography (EMG), a technique used to analyze and record electric current produced by skeletal muscles, has been used to control replacement limbs, and diagnose muscle irregularities. In this work, an EMG based system comprising of an orthotic arm and finger device to aid in muscle rehabilitation, is presented. As the user attempts to contract their bicep or forearm muscles, the system senses the change in the EMG signals and in turn triggers the motors to assist with flexion and extension of the arm and fingers. As brain is a major factor for muscle growth, mental training using motor imagery was incorporated into the system. Subjects underwent mental training to show the capability of muscle growth. The measured data reveals that the subjects were able to compensate for the loss of muscle growth, due to shorter physical training sessions, with mental training. Subjects were then tested using the orthotic arm and finger rehabilitation device with motor imagery. The findings also showed a positive increase in muscle growth using the rehabilitation system. Based on the experimental results, the EMG rehabilitation system presented in this paper has the potential to increase muscle strength and improve the recovery rate for muscle injuries, partial paralysis, or muscle irregularities.

via Electromyography Based Orthotic Arm and Finger Rehabilitation System – IEEE Conference Publication

, , , , , , , , , , ,

Leave a comment

[Abstract] Kinect V2 as a tool for stroke recovery: Pilot study of motion scale monitoring


This paper investigates Kinect device application during rehabilitation of people with an ischemic stroke. There are many similar application using Kinect as a tool during rehabilitation. This paper is focused on measurement of Kinect’s spatial accuracy and proposition of body states and exercises according to the Motor assessment scale for stroke (MAS). The system observes the whole rehabilitation process and objectively compares ranges of movement during each exercise. Angles between limbs are computed in the skeletal body joints projection to three anatomical planes, which enables a better insight to subject performance. The system is easily implemented with a consumer-grade computer and a low-cost Kinect device. Selected exercises are presented together with the angles evolution, body states recognition and the MAS Scale after the stroke classification.

Source: Kinect V2 as a tool for stroke recovery: Pilot study of motion scale monitoring – IEEE Xplore Document

, , , , , , , , , ,

Leave a comment

[ARTICLE] User-centred input for a wearable soft-robotic glove supporting hand function in daily life


Many stroke patients and elderly have a reduced hand function, resulting in difficulties with independently performing activities of daily living (ADL). Assistive technology is a promising alternative to support the upper limb in performing ADL. To avoid device abandonment, end-users should be involved early in the design and development phase to identify user requirements for assistive technology.

The present study applies a user-centred approach to identify user requirements for wearable soft-robotic gloves targeted at physical support of hand function during ADL for elderly and stroke patients.

Elderly, stroke patients and healthcare professionals, participating in focus groups, specified requirements regarding:

  1. activities that need support of assistive technology,
  2. design of wearable robotic devices for hand support, and
  3. application of assistive technology as training tool at home.

Assistive technology for the support of the hand is considered valuable by users for assisting ADL, but only if the device is wearable, compact, lightweight, easy to use, quickly initialized, washable and only supports the particular function(s) that an individual need(s) assistance with, without taking over existing function(s) from the user.

Source: IEEE Xplore Abstract – User-centred input for a wearable soft-robotic glove supporting hand function in daily life

, , , , , , , , , , , , ,

Leave a comment

%d bloggers like this: