Evaluating EEG–EMG Fusion-Based Classification as a Method for Improving Control of Wearable Robotic Devices for Upper-Limb Rehabilitation

Musculoskeletal disorders are the biggest cause of disability worldwide, and wearable mechatronic rehabilitation devices have been proposed for treatment. However, before widespread adoption, improvements in user control and system adaptability are required. User intention should be detected intuitively, and user-induced changes in system dynamics should be unobtrusively identified and corrected. Developments often focus on model-dependent nonlinear control theory, which is challenging to implement for wearable devices. One alternative is to incorporate bioelectrical signal-based machine learning into the system, allowing for simpler controller designs to be augmented by supplemental brain (electroencephalography/EEG) and muscle (electromyography/EMG) information. To extract user intention better, sensor fusion techniques have been proposed to combine EEG and EMG; however, further development is required to enhance the capabilities of EEG–EMG fusion beyond basic motion classification. To this end, the goals of this thesis were to investigate expanded methods of EEG–EMG fusion and to develop a novel control system based on the incorporation of EEG–EMG fusion classifiers. A dataset of EEG and EMG signals were collected during dynamic elbow flexion–extension motions and used to develop EEG–EMG fusion models to classify task weight, as well as motion intention. A variety of fusion methods were investigated, such as a Weighted Average decision-level fusion (83.01 ± 6.04% accuracy) and Convolutional Neural Network-based input-level fusion (81.57 ± 7.11% accuracy), demonstrating that EEG–EMG fusion can classify more indirect tasks. A novel control system, referred to as a Task Weight Selective Controller (TWSC), was implemented using a Gain Scheduling-based approach, dictated by external load estimations from an EEG–EMG fusion classifier. To improve system stability, classifier prediction debouncing was also proposed to reduce misclassifications through filtering. Performance of the TWSC was evaluated using a developed upper-limb brace simulator. Due to simulator limitations, no significant difference in error was observed between the TWSC and PID control. However, results did demonstrate the feasibility of prediction debouncing, showing it provided smoother device motion. Continued development of the TWSC, and EEG–EMG fusion techniques will ultimately result in wearable devices that are able to adapt to changing loads more effectively, serving to improve the user experience during operation

Accessibility of Health Data Representations for Older Adults: Challenges and Opportunities for Design

Health data of consumer off-the-shelf wearable devices is often conveyed to users through visual data representations and analyses. However, this is not always accessible to people with disabilities or older people due to low vision, cognitive impairments or literacy issues. Due to trade-offs between aesthetics predominance or information overload, real-time user feedback may not be conveyed easily from sensor devices through visual cues like graphs and texts. These difficulties may hinder critical data understanding. Additional auditory and tactile feedback can also provide immediate and accessible cues from these wearable devices, but it is necessary to understand existing data representation limitations initially. To avoid higher cognitive and visual overload, auditory and haptic cues can be designed to complement, replace or reinforce visual cues. In this paper, we outline the challenges in existing data representation and the necessary evidence to enhance the accessibility of health information from personal sensing devices used to monitor health parameters such as blood pressure, sleep, activity, heart rate and more. By creating innovative and inclusive user feedback, users will likely want to engage and interact with new devices and their own data

A Review of Resonant Converter Control Techniques and The Performances

paper first discusses each control technique and then gives experimental results and/or performance to highlights their merits. The resonant converter used as a case study is not specified to just single topology instead it used few topologies such as series-parallel resonant converter (SPRC), LCC resonant converter and parallel resonant converter (PRC). On the other hand, the control techniques presented in this paper are self-sustained phase shift modulation (SSPSM) control, self-oscillating power factor control, magnetic control and the H-∞ robust control technique

Evidence Synthesis of Shoulder Pain Among Canadian Firefighters

Injury or degeneration of rotator cuff tendon leads to rotator cuff disease (subacromial impingement syndrome and rotator cuff tears). Shoulder pain – pain in the upper arm close to the deltoid muscle insertion has been reported as the most common symptom for subacromial impingement syndrome and rotator cuff tears. However, the current state of evidence on treatment effectiveness of rotator cuff disease is indeterminate. The shoulder function is essential for many of the physically demanding tasks that firefighters perform on the fire ground. For fire services and firefighters, the preservation of active duty is critical for their continued service to their communities. However, the prevalence of shoulder pain among Canadian firefighters has not been synthesized. Further, high quality randomized clinical trials (RCTs) provide the highest level of evidence and assist in clinical decision making. The International Committee of Medical Journal Editors (ICMJE) recommendation of RCT trial registration in public trials registry has been made to improve the reporting, transparency, rigor and reproducibility in RCTs. However, there is a paucity of evidence on the proportion of RCTs with proper trial registrations in the field of rehabilitation therapy. Therefore, the purposes of this thesis were 1) to assess the effects of arthroscopic versus mini-open rotator cuff repair surgery on function, pain and range of motion at in patients with rotator cuff tears; 2) to quantify the effects of surgical vs conservative interventions on clinical outcomes of pain and function in patients with subacromial impingement syndrome; 3) to assess the prevalence of musculoskeletal disorders (MSDs) among Canadian firefighters, 4) to examine the proportion of RCTs that were reported to have been prospectively, retrospectively registered or not registered in the field of rehabilitation therapy, and 5) to use the synthesized evidence to inform the design of a single center (fire-station), investigator-blinded, randomized, 12-month, parallel-group, superiority trial for the evaluation of the efficacy of a shoulder exercises on clinical outcomes in firefighters with shoulder pain. From the existing literature, we found evidence that both arthroscopic and mini-open techniques to rotator cuff repairs with post-operative rehabilitation exercises were effective in improving clinical outcomes of function, pain and shoulder range of motion in patients with rotator cuff tears. However, the between-group differences in outcomes were too small to be clinically important. The effects of surgery plus physiotherapy (exercises) vs physiotherapy (exercises) alone on pain and function were too small to be clinically important at 3-, 6-months, 1-, 2-, 5- and ≥ 10-years follow up. This further highlighted that rehabilitation exercises be considered as the first treatment approach in patients with shoulder pain. We also identified high point-prevalence estimates (1 in 4 firefighters) of shoulder-, back-, and knee-related MSDs among Canadian firefighters (shoulder pain was 23%). Our review study indicated that fifteen years after the introduction of standards for RCT registration by ICMJE, only one-third of the RCTs in the field of rehabilitation therapy were prospectively registered. Subsequently, the emergence of further evidence (observational studies in firefighters and RCTs in active-duty military personnel) indicating the clinical effectiveness of occupation-specific rehabilitation exercises along with our evidence syntheses provided the rationale for the design and conduct of an RCT to assess the effectiveness of firefighter-specific rehabilitation exercises among Canadian firefighter with shoulder pain