Design and Validation of a Minimal Complexity Algorithm for Stair Step Counting

Wearable sensors play a significant role for monitoring the functional ability of the elderly and in general, promoting active ageing. One of the relevant variables to be tracked is the number of stair steps (single stair steps) performed daily, which is more challenging than counting flight of stairs and detecting stair climbing. In this study, we proposed a minimal complexity algorithm composed of a hierarchical classifier and a linear model to estimate the number of stair steps performed during everyday activities. The algorithm was calibrated on accelerometer and barometer recordings measured using a sensor platform worn at the wrist from 20 healthy subjects. It was then tested on 10 older people, specifically enrolled for the study. The algorithm was then compared with other three state-of-the-art methods, which used the accelerometer, the barometer or both. The experiments showed the good performance of our algorithm (stair step counting error: 13.8%), comparable with the best state-of-the-art (p > 0.05), but using a lower computational load and model complexity. Finally, the algorithm was successfully implemented in a low-power smartwatch prototype with a memory footprint of about 4 kB

Eccentric Squat Loading as means to Assessing Physical Function in Seniors

Healthy aging is a key concern for Canada’s aging population. Investigating methods that assist and promote healthy aging is therefore important to inform on this matter. The maintenance of functional ability, rather, the ability to conduct everyday tasks and perform the functions necessary for everyday life is crucial to assist in the healthy aging process (Lehto et. al., 2017, Arena et. al., 2007). In regard to functional ability, muscle strength and muscle power are two key factors in defining performance. A method of properly assessing these outputs leads to a determination of an individual’s functional performance level and potential interventions to mitigate declining function with age. Traditionally, muscle strength and power have been assessed using an isokinetic dynamometer, but this comes with limitations such as its high cost and the accessibility. Muscle strength and muscle power have commonly been maintained through strength and power training. This type of training has limitations that eccentric training may overcome. Isoinertial flywheel devices, such as the kBox (Exxentric), not only have the potential to produce eccentric overload necessary for eccentric training, but they are also capable of recording velocity and power outputs. The kBox may be beneficial to the aging population to determine functional ability and provide a method for eccentric training while overcoming the limitations of the dynamometer. Therefore, investigation into the kBox capabilities regarding the reliability and validity of measured outputs as well as the potential to predict functional ability is necessary. This study had three objectives: 1) To determine the relationship of the kBox power outputs in comparison to the “gold standard” dynamometer. Researchers hypothesized that the kBox would display good validity and be correlated with the measured outputs of the dynamometer; 2) To determine if the kBox measured outputs and/or the dynamometer measured outputs predicted functional performance by comparing outputs to three functional tests. Researchers hypothesized that the kBox would be more predictive of functional performance due to its multi-joint movement; 3) To investigate sEMG and muscle oxygenation levels across the various modalities tested to gain insight into the physiological responses accompanying each movement. Researchers hypothesized the kBox SPT would produce greater muscle activation as well as greater muscle deoxygenation compared to testing on the isokinetic dynamometer. A total of 26 strength trained individuals (62.6 6.2 yrs old) were recruited and volunteered to participate in this study. Participants completed three functional tests; the timed-up-and-go test, the five time sit-to-stand test, and the stair climb power test. Participants also completed the kBox Squat Power Test (SPT) as well as dynamometer concentric, isometric and eccentric tests. Muscle activation and muscle oxygenation were recorded across modalities when possible. For the first hypothesis, Pearson’s correlations displayed the flywheel SPT to have high correlations with the dynamometer power and strength outputs, confirming the SPT has high concurrent validity when measuring a senior population during the SPT protocol. For the second hypothesis, the dynamometer results were more predictive of outcomes on the three functional tests than the kBox ( Pearson’s correlation and stepwise multiple linear regression tests). Last, no significant differences between muscle activation or muscle oxygenation were found across modalities through ANOVA and Tukey post-hoc tests. Results of this study display the potential the isoinertial kBox has for future clinical settings. The good relationship/validity, along with the prediction of some functional tests demonstrates its usage for further studies and quantification of muscle outputs for various exercises. These findings suggest the kBox may be used in the future to determine functional performance, overcoming the limitations of the dynamometer. Additionally, this study displayed the SPT protocol can be conducted safely and successfully by a senior population meaning the kBox can overcome the limitations set forth by traditional strength and power training such as a decrease in cost for the equipment and easier accessibility for senior population

Body sensor networks: smart monitoring solutions after reconstructive surgery

Advances in reconstructive surgery are providing treatment options in the face of major trauma and cancer. Body Sensor Networks (BSN) have the potential to offer smart solutions to a range of clinical challenges. The aim of this thesis was to review the current state of the art devices, then develop and apply bespoke technologies developed by the Hamlyn Centre BSN engineering team supported by the EPSRC ESPRIT programme to deliver post-operative monitoring options for patients undergoing reconstructive surgery. A wireless optical sensor was developed to provide a continuous monitoring solution for free tissue transplants (free flaps). By recording backscattered light from 2 different source wavelengths, we were able to estimate the oxygenation of the superficial microvasculature. In a custom-made upper limb pressure cuff model, forearm deoxygenation measured by our sensor and gold standard equipment showed strong correlations, with incremental reductions in response to increased cuff inflation durations. Such a device might allow early detection of flap failure, optimising the likelihood of flap salvage. An ear-worn activity recognition sensor was utilised to provide a platform capable of facilitating objective assessment of functional mobility. This work evolved from an initial feasibility study in a knee replacement cohort, to a larger clinical trial designed to establish a novel mobility score in patients recovering from open tibial fractures (OTF). The Hamlyn Mobility Score (HMS) assesses mobility over 3 activities of daily living: walking, stair climbing, and standing from a chair. Sensor-derived parameters including variation in both temporal and force aspects of gait were validated to measure differences in performance in line with fracture severity, which also matched questionnaire-based assessments. Monitoring the OTF cohort over 12 months with the HMS allowed functional recovery to be profiled in great detail. Further, a novel finding of continued improvements in walking quality after a plateau in walking quantity was demonstrated objectively. The methods described in this thesis provide an opportunity to revamp the recovery paradigm through continuous, objective patient monitoring along with self-directed, personalised rehabilitation strategies, which has the potential to improve both the quality and cost-effectiveness of reconstructive surgery services.Open Acces

A pervasive body sensor network for monitoring post-operative recovery

Over the past decade, miniaturisation and cost reduction brought about by the semiconductor industry has led to computers smaller in size than a pin head, powerful enough to carry out the processing required, and affordable enough to be disposable. Similar technological advances in wireless communication, sensor design, and energy storage have resulted in the development of wireless “Body Sensor Network (BSN) platforms comprising of tiny integrated micro sensors with onboard processing and wireless data transfer capability, offering the prospect of pervasive and continuous home health monitoring. In surgery, the reduced trauma of minimally invasive interventions combined with initiatives to reduce length of hospital stay and a socioeconomic drive to reduce hospitalisation costs, have all resulted in a trend towards earlier discharge from hospital. There is now a real need for objective, pervasive, and continuous post-operative home recovery monitoring systems. Surgical recovery is a multi-faceted and dynamic process involving biological, physiological, functional, and psychological components. Functional recovery (physical independence, activities of daily living, and mobility) is recognised as a good global indicator of a patient’s post-operative course, but has traditionally been difficult to objectively quantify. This thesis outlines the development of a pervasive wireless BSN system to objectively monitor the functional recovery of post-operative patients at home. Biomechanical markers were identified as surrogate measures for activities of daily living and mobility impairment, and an ear-worn activity recognition (e-AR) sensor containing a three-axis accelerometer and a pulse oximeter was used to collect this data. A simulated home environment was created to test a Bayesian classifier framework with multivariate Gaussians to model activity classes. A real-time activity index was used to provide information on the intensity of activity being performed. Mobility impairment was simulated with bracing systems and a multiresolution wavelet analysis and margin-based feature selection framework was used to detect impaired mobility. The e-AR sensor was tested in a home environment before its clinical use in monitoring post-operative home recovery of real patients who have undergone surgery. Such a system may eventually form part of an objective pervasive home recovery monitoring system tailored to the needs of today’s post-operative patient.Open acces

Biofeedback Based Physical Rehabilitation in Parkinson's Disease Aimed at Self-Enhancement

Parkinson’s disease (PD) is a progressive neuromotor disorder that results in a progressive deterioration of balance and motor abilities with a consequent increase of the risk of falls and a reduction of quality of life. Physical therapy revealed to be fit for the symptomatic treatment of the disease and the adoption of biofeedback signals showed to be effective in prolonging the benefits of the therapy. Thus, this doctoral project has been designed to assess the benefits that wearable technologies for biofeedback generation could have in physical therapy. To further improve the developed biofeedback-based system, the assessment of new methods for the objective evaluation of balance control was included into the study. The dissertation is divided into three different set of studies, respectively aimed at: 1) presenting new wearable systems specifically designed for biofeedback-based rehabilitation; 2) assessing proprioceptive impairments in PD subjects through the adoption of a robotic platform to destabilize the base of support; 3) discussing new methods for the evaluation of balance preceding the execution of voluntary movements. The efficacy of the main proposed solution was assessed in a 6-months RCT study by comparison of subjects with PD trained with the biofeedback system and patients that received usual care. Both clinical and instrumental outcomes supported the higher efficacy of the biofeedback-based approach. The developed instrumented tests showed good sensitivity in discriminating patients and in detecting changes induced by physical therapy. The results reported in this thesis lead to the conclusion that the adoption of biofeedback based physical rehabilitation systems is promising in the treatment of Parkinson’s disease. The availability of a set of fast, easy-to-manage tests for the evaluation of balance and motor control might be useful in the design of home-delivered, user-tailored exercises for both healthy elderly and neurological subjects

Humanoid Robots

For many years, the human being has been trying, in all ways, to recreate the complex mechanisms that form the human body. Such task is extremely complicated and the results are not totally satisfactory. However, with increasing technological advances based on theoretical and experimental researches, man gets, in a way, to copy or to imitate some systems of the human body. These researches not only intended to create humanoid robots, great part of them constituting autonomous systems, but also, in some way, to offer a higher knowledge of the systems that form the human body, objectifying possible applications in the technology of rehabilitation of human beings, gathering in a whole studies related not only to Robotics, but also to Biomechanics, Biomimmetics, Cybernetics, among other areas. This book presents a series of researches inspired by this ideal, carried through by various researchers worldwide, looking for to analyze and to discuss diverse subjects related to humanoid robots. The presented contributions explore aspects about robotic hands, learning, language, vision and locomotion

Cyber-Human Systems, Space Technologies, and Threats

CYBER-HUMAN SYSTEMS, SPACE TECHNOLOGIES, AND THREATS is our eighth textbook in a series covering the world of UASs / CUAS/ UUVs / SPACE. Other textbooks in our series are Space Systems Emerging Technologies and Operations; Drone Delivery of CBNRECy – DEW Weapons: Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD); Disruptive Technologies with applications in Airline, Marine, Defense Industries; Unmanned Vehicle Systems & Operations On Air, Sea, Land; Counter Unmanned Aircraft Systems Technologies and Operations; Unmanned Aircraft Systems in the Cyber Domain: Protecting USA’s Advanced Air Assets, 2nd edition; and Unmanned Aircraft Systems (UAS) in the Cyber Domain Protecting USA’s Advanced Air Assets, 1st edition. Our previous seven titles have received considerable global recognition in the field. (Nichols & Carter, 2022) (Nichols, et al., 2021) (Nichols R. K., et al., 2020) (Nichols R. , et al., 2020) (Nichols R. , et al., 2019) (Nichols R. K., 2018) (Nichols R. K., et al., 2022)https://newprairiepress.org/ebooks/1052/thumbnail.jp