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This paper addresses the design procedures and simulation results from the mechatronic model of the rehabilitation equipment, which can improve the functionality and precision of the ambulatory gait training system. The distinguishing feature of mechatronic systems is the achievement of system functionality through intensive integration. The paper demonstrates how the mechatronic design modeling has helped improve the design and performance of the new rehabilitation equipment built by the authors and is known as Navigaitor. The Navigaitor is designed to aid the patients who need to improve their balance and walk. The mechatronics aspects allow a better understanding of the dynamic behavior and interactions of the components. Depending on the severity of the patient’s injury (stroke survivor, Parkinson, etc.), the oscillatory motion can range from uniform to non-uniform. The motion needs to be converted from the oscillatory sinusoidal motion of the patient into linear motion that the system can follow the patient with minimum lag and maximum stability. The data acquired during the training stage showing a different rate of recovery and response assists the system designers and thereby provides input to fine-tune the system and upgrade the control requirements.

 

Quantitative assessment of movement using motion capture provides insights on mobility which are not evident from clinical evaluation. Here, in older individuals that were healthy or had suffered a stroke, we aimed to investigate their balance in terms of changes in body kinematics and muscle activity. Our research question involved determining the effects on post- compared to pre-sensorimotor training exercises on maintaining or improving balance. Our research hypothesis was that training would improve the gait and balance by increasing joint angles and extensor muscle activities in lower extremities and spatiotemporal measures of stroke and elderly people. This manuscript describes a motion capture-based evaluation protocol to assess joint angles and spatiotemporal parameters (cadence, step length and walking speed), as well as major extensor and flexor muscle activities. We also conducted a case study on a healthy older participant (male, age, 65) and an older participant with chronic stroke (female, age, 55). Both participants performed a walking task along a path with a rectangular shape which included tandem walking forward, right side stepping, tandem walking backward, left side stepping to the starting location. For the stroke participant, the training improved the task completion time by 19 s. Her impaired left leg had improved step length (by 0.197 m) and cadence (by 10 steps/min) when walking forward, and cadence (by 12 steps/min) when walking backward. The non-impaired right leg improved cadence when walking forward (by 15 steps/min) and backward (by 27 steps/min). The joint range of motion (ROM) did not change in most cases. However, the ROM of the hip joint increased significantly by 5.8 degrees (p = 0.019) on the left leg side whereas the ROMs of hip joint and knee joint increased significantly by 4.1 degrees (p = 0.046) and 8.1 degrees (p = 0.007) on the right leg side during backward walking. For the healthy participant, the significant changes were only found in his right knee joint ROM having increased by 4.2 degrees (p = 0.031) and in his left ankle joint ROM having increased by 5.5 degrees (p = 0.006) during the left side stepping. 

Increasing balance confidence in older individuals is important towards improving their quality of life and reducing activity avoidance. Here, we investigated if balance confidence (perceived ability) and balance performance (ability) in older adults were related to one another and would improve after balance training. The relationship of balance confidence in conjunction with balance performance for varied conditions (such as limiting vision, modifying somatosensory cues, and also base of support) was explored. We sought to determine if balance confidence and ability, as well as their relationship, could change after several weeks of training. Twenty-seven healthy participants were trained for several weeks during standing and walking exercises. In addition, seven participants with a higher risk of imbalance leading to falls (survivors of stroke) were also trained. Prior to and after training, balance ability and confidence were assessed via the Balance Error Scoring System (BESS) and Activities Specific Balance Confidence (ABC) Scale, respectively. Both groups showed improvements in balance abilities (i.e., BESS errors significantly decreased after training). Balance confidence was significantly higher in the healthy group than in the stroke group; however, ABC results reflected that balance confidence did not significantly increase after training for each. The correlations between balance ability and balance confidence were explored. Encouragingly, healthy participants displayed a negative correlation between BESS errors and ABC (i.e., enhancements in balance confidence (increases in ABC Scale results) were related to improvements in balance ability (decreases in BESS errors)). For the stroke participants, despite improvements in balance ability, our results showed that there was no relation to balance confidence (i.e., no correlation between BESS errors and ABC) in this group. 

For the rapidly growing aging demographic worldwide, robotic training methods could be impactful towards improving balance critical for everyday life. Here, we investigated the hypothesis that non-bodyweight supportive (nBWS) overground robotic balance training would lead to improvements in balance performance and balance confidence in older adults. Sixteen healthy older participants (69.7 ± 6.7 years old) were trained while donning a harness from a distinctive NaviGAITor robotic system. A control group of 11 healthy participants (68.7 ± 5.0 years old) underwent the same training but without the robotic system. Training included 6 weeks of standing and walking tasks while modifying: (1) sensory information (i.e., with and without vision (eyes-open/closed), with more and fewer support surface cues (hard or foam surfaces)) and (2) base-of-support (wide, tandem and single-leg standing exercises). Prior to and post-training, balance ability and balance confidence were assessed via the balance error scoring system (BESS) and the Activities specific Balance Confidence (ABC) scale, respectively. Encouragingly, results showed that balance ability improved (i.e., BESS errors significantly decreased), particularly in the nBWS group, across nearly all test conditions. This result serves as an indication that robotic training has an impact on improving balance for healthy aging individuals. 

Hyperspectral imaging is an area of active research with many applications in remote sensing, mineral exploration, and environmental monitoring. Deep learning and, in particular, convolution-based approaches are the current state-of-the-art classification models. However, in the presence of noisy hyperspectral datasets, these deep convolutional neural networks underperform. In this paper, we proposed a feature augmentation approach to increase noise resistance in imbalanced hyperspectral classification. Our method calculates context-based features, and it uses a deep convolutional neuronet (DCN). We tested our proposed approach on the Pavia datasets and compared three models, DCN, PCA + DCN, and our context-based DCN, using the original datasets and the datasets plus noise. Our experimental results show that DCN and PCA + DCN perform well on the original datasets but not on the noisy datasets. Our robust context-based DCN was able to outperform others in the presence of noise and was able to maintain a comparable classification accuracy on clean hyperspectral images. 

To bridge the gap between the biological sciences (typically female-dominated) and engineering (typically male-dominated), biomedical engineering (BME) activities could potentially be used as a vehicle to alter female students' perception of engineering as a whole. Female's pursuit of STEM (Science, Technology, Engineering and Math) degrees is typically confined to the biological sciences and females earn a high proportion of degrees in nursing, psychology and the social sciences, yet male presence persists in physical sciences and engineering. Female's participation in engineering remains much lower than men at all degree levels. Here, research questions included do female high school students: 1) perceive engineering as relevant? 2) have an interest & aptitude towards exploring engineering in college and as a career? 3) have anxiety in terms of engineering? 4) have engineering "role-confidence"? Participants, a randomly selected pool of 28 high school students (almost exclusively female from schools throughout the DC Metro area) took part in a week-long, all-day workshop where they were exposed to female engineering mentors, peers, and activities tied to BME & Engineering. Pre and post surveys, adapted from standard STEM surveys, were administered to the pool of participants. Increases in confidence and interest in engineering and decreased anxiety were observed following female high school students' participation in hands-on activities in BME. 

With the massive growth of the aging population worldwide, of utmost importance is reducing falls. Critical to reducing fall risk is one's ability to weight incoming sensory information towards maintaining balance. The purpose of this research was to investigate if simple, targeted sensory training on aging individuals (50 - 80 years old), including twelve healthy and eight individuals with chronic stroke, could improve their balance. Repeated sensory training targeted visual (via eyes-open/closed) and somatosensory inputs (via light touch to the fingertip as well as hard, soft foam, and hard foam support surfaces to the feet) during standing and dynamic base-of-support (BOS) exercises. Study participants underwent six weeks of training. Prior to and post training, standing balance was assessed via a simple, clinical measure: the balance error scoring system (BESS). Following several weeks of training, participants showed significant improvements in BESS errors: healthy participants for small BOS with limited somatosensory information (i.e., tandem and single-leg standing on foam) and participants with stroke in all conditions.Clinical Relevance- This research study demonstrated that simple, accessible exercises, can positively impact balance in the aging population, a pressing need.