Scholarly Works, Industrial and Systems Engineering

Permanent URI for this collection

https://hdl.handle.net/10919/24292

Research articles, presentations, and other scholarship

Browse

Now showing 1 - 20 of 529

Using musculoskeletal models to estimate the effects of exoskeletons on spine loads during dynamic lifting tasks: differences between OpenSim and the AnyBody modelling system
Behjati Ashtiani, Mohamad; Akhavanfar, Mohammadhossein; Li, Lingyu; Kim, Sunwook; Nussbaum, Maury A. (Elsevier, 2025-05-23)
Occupational back-support exoskeletons (BSEs) can reduce physical demands during lifting by providing assistive torques, but their effects on spine loading are poorly understood. In this study, we used two common musculoskeletal models developed in OpenSim and the AnyBody Modeling System to estimate intervertebral joint forces (IJF) during asymmetric and symmetric lifting tasks with and without BSEs. Data from an earlier study were used, involving 18 participants who performed repetitive lowering/lifting in three task conditions and with three different BSEs (along with a control condition using no BSE). We simulated the tasks with both models and estimated axial compression and anteroposterior shear forces at the L4/L5 joint and derived peak values (95th percentile) as outcome measures. OpenSim estimated significantly larger axial compression and anteroposterior shear forces than AMS. Both models estimated reductions in spine loading when using either of the BSEs, though OpenSim estimated greater reductions than AMS. Strong positive, linear relationships (r > 0.95) between the two model estimates were found for axial compression, while much weaker and even negative relationships were observed for shear forces, especially under asymmetric conditions. The differences in model estimates were likely due to variations in model assumptions and passive tissue representations. Future research should explore more detailed human-exoskeleton interaction models, evaluate the impact of modelling assumptions on IJF estimates, and assess the agreement of these findings with in vivo measurements such as electromyography.
Effectiveness and usability of a trunk posture feedback system: An exploratory, longitudinal study for up to 10 days among vehicle assembly operators
Choi, Jiwon; Kim, Sunwook; Lim, Sol; Porto, Ryan; Nussbaum, Maury A. (Elsevier, 2025-10)
Postural feedback systems are a potential ergonomic intervention to reduce postural exposures, and thus musculoskeletal disorder risk, but field-based evidence of their longer-term effectiveness remains limited. We conducted an exploratory investigation of a commercial postural feedback system, which provided auditory and vibrotactile feedback following excessive trunk motion, in vehicle manufacturing. Eight workers used the system during regular shifts for up to 10 workdays. We observed a reduction in “poor” postures on the first day of feedback. However, these benefits diminished over time, possibly due to a novelty effect—with improvements diminishing as participants adapted to the system—and effects varied greatly across participants. Participant responses were mixed; some reported improved postural awareness while others found the feedback irritating and often ignored it. Findings from this exploratory study suggest the importance of enhancing postural feedback system design to sustain behavioral change over time and better support individual needs.
Two Novel Slip Training Methods Improve the Likelihood of Recovering Balance After a Laboratory-Induced Slip
Allin, Leigh J.; Nussbaum, Maury A.; Madigan, Michael L. (Human Kinetics, 2018-08-06)
Task-specific balance training is an approach to fall prevention that has the potential to reduce the number of slip-induced falls. However, a limitation of current task-specific training methods is that they require nontrivial financial and/or equipment resources. This pilot study evaluated the efficacy of 2 low-cost, low-tech methods for slip-recovery training in improving balance recovery ability. The 2 methods were as follows: (1) repeated unexpected slip training (UST), which involved repeated unexpected slips while walking (similar to current methods of task-specific slip-recovery training) and (2) volitional sliprecovery training (VST), which involved practicing a slip recovery response after volitionally stepping to induce a slip-like perturbation. A total of 36 young adults completed 1 training session (UST, VST, or control), followed by 1 unexpected, laboratory-induced slip while walking on the following day. Compared with controls, UST and VST resulted in a higher proportion of successful balance recoveries from the laboratory-induced slips. UST improved both proactive control and the reactive stepping response after slipping, whereas VST improved the ability to arrest the motion of the slipping foot. Based on these preliminary results, UST and VST may provide practical, cost-effective methods for slip-recovery training.
Required friction during overground walking is lower among obese compared to non-obese older men, but does not differ with obesity among women
Arena, Sara L.; Garman, Christina R.; Nussbaum, Maury A.; Madigan, Michael L. (Elsevier, 2017-02-27)
Obesity and aging have been independently associated with altered required friction during walking, but it is unclear how these factors interact to influence the likelihood of slipping. Therefore, the purpose of this study was to determine whether there are differences related to obesity and aging on required friction during overground walking. Fourteen older non-obese, 11 older obese, 20 younger non-obese, and 20 younger obese adults completed walking trials at both a self-selected and hurried speed. When walking at a hurried speed, older obese men walked at a slower gait speed and exhibited lower frictional demands compared both to older non-obese men and to younger obese men. No differences in required friction were found between non-obese and obese younger adults. These results suggest that the increased rate of falls among obese or older adults is not likely due to a higher risk of slip initiation.
Relative Effort while Walking Is Higher among Women Who Are Obese, and Older Women
Koushyar, Hoda; Anderson, Dennis E.; Nussbaum, Maury A.; Madigan, Michael L. (Lippincott Williams & Wilkins, 2019-07-23)
Purpose: Individuals who are obese, and older individuals, exhibit gait alterations that may result, in part, from walking with greater effort relative to their maximum strength capacity. The goal of this study was to investigate obesity-related and age-related differences in relative effort during gait. Methods: Four groups of women completed the study, including 10 younger healthy-weight, 10 younger obese, 10 older healthy-weight, and 9 older obese women. The protocol included strength measurements at the hip, knee, and ankle in both flexion and extension, and gait trials under self-selected and constrained (1.5 m·s-1 gait speed and 0.65-m step length) conditions. Relative effort was calculated as the ratio of joint torques during gait, and strength from a subject-specific model that predicted strength as a function of joint angle. Results: Relative effort during self-selected gait was higher among women who were obese in knee extension (P = 0.028) and ankle plantar flexion (P = 0.013). Although both joint torques and strength were higher among women who were obese, these increases in relative effort were attributed to greater obesity-related increases in joint torques than strength. Relative effort was also higher among older women in hip flexion (P < 0.001) and knee extension (P = 0.008), and attributed to age-related strength loss. Results were generally similar between self-selected and constrained gait, indicating the greater relative effort among women who were obese and older women was not attributed to differences in gait spatiotemporal characteristics. Conclusions: Women who were obese, as well as older women, walk with greater relative effort. These results may help explain the compromised walking ability among these individuals.
Obesity as a Factor Contributing to Falls by Older Adults
Madigan, Michael L.; Rosenblatt, Noah J.; Grabiner, Mark D. (Springer, 2014-05-24)
The growth of the worldwide population of older adults presents significant challenges, many inter-related, that range from the health of individuals to the health of national economies. In the US, more than one-third of older adults may be obese, a condition that may independently increase the risk for mobility impairment, fall-related injury and, possibly, costs of post-injury treatment and care. The effectiveness of conventional exercise-based fall prevention programs is significant but smaller than both the annual rate of falling of older adults and rate of growth of this population, who are at greatest risk for injurious falls. The anthropometric and functional consequences of obesity may impose limitations on the ability to perform compensatory stepping responses following large postural disturbances. The focus of this paper is the potential of task-specific training to improve compensatory stepping responses and reduce falls by obese people given the individual-specific anthropometric and functional consequences of obesity.
Impaired plantar sensitivity among the obese is associated with increased postural sway
Wu, Xuefang; Madigan, Michael L. (Elsevier, 2014-09-19)
Impaired foot plantar sensitivity has been hypothesized among individuals who are obese, and may contribute to their impaired balanced during quiet standing. The objective of this study was to investigate the effects of obesity on plantar sensitivity, and explore the relationship between plantar sensitivity and balance during quiet standing. Thirty-nine young adults from the university population participated in the study including 19 obese and 20 non-obese adults. Plantar sensitivity was measured as the force threshold at which an increasing force applied to the plantar surface of the foot was first perceived, and the force threshold at which a decreasing force was last perceived. Measurements were obtained while standing, and at two locations on the plantar surface of the dominant foot. Postural sway during quiet standing was then measured under three different sensory conditions. Results indicated less sensitive plantar sensitivity and increased postural sway among the obese, and statistically significant correlations between plantar sensitivity and postural sway that were characterized as weak to moderate in strength. As such, impaired plantar sensitivity among individuals who are obese may be a mechanism by which obesity degrades standing balance among these individuals.
Feet kinematics upon slipping discriminate between recoveries and three types of slip-induced falls
Allin, Leigh J.; Nussbaum, Maury A.; Madigan, Michael L. (Taylor & Francis, 2018-01-03)
This study investigated the relationship between feet kinematics upon slipping while walking and the outcome of the slip. Seventy-one slips (induced by walking over an unexpectedly slippery surface) were analysed, which included 37 recoveries, 16 feet-split falls, 11 feet-forward falls and seven lateral falls. Feet kinematics differed between recoveries and three types of slip-induced falls, and a discriminant model including six measures of feet kinematics correctly predicted 87% of slip outcomes. Two potentially modifiable characteristics of the feet kinematics upon slipping that can improve the likelihood of successfully averting a fall were identified: (1) quickly arresting the motion of the slipping foot and (2) a recovery step that places the trailing toe approximately 0–10% body height anterior to the sacrum. These results may inform the development of task-specific balance training interventions that promote favourable recovery responses to slipping. Practitioner Summary: This study investigated the relationship between feet movements upon slipping and outcomes of the slip. Potentially modifiable characteristics that can reduce the likelihood of falling were: (1) quickly arresting slipping foot motion and (2) a recovery step that places the trailing toe approximately 0–10% body height anterior to the sacrum.
Falls resulting from a laboratory-induced slip occur at a higher rate among individuals who are obese
Allin, Leigh J.; Wu, Xuefang; Nussbaum, Maury A.; Madigan, Michael L. (Elsevier, 2016-02-06)
Falls due to slipping are a serious concern, with slipping estimated to cause 40-50% of all fall-related injuries. Epidemiological data indicates that older and obese adults experience more falls than young, non-obese individuals. An increasingly heavier and older U.S. population and workforce may be exacerbating the problem of slip-induced falls. The purpose of this study was to investigate the effects of obesity and age on slip severity and rate of falling resulting from laboratory-induced slips. Four groups of participants (young obese, young non-obese, older obese, older non-obese) were slipped while walking at a self-selected, slightly hurried pace. Slip severity (slip distance, slip duration, mean slip speed and peak slip speed) and slip outcome (fall or recovery) were compared between groups. Obese individuals experienced 22% faster slips than non-obese individuals in terms of mean slip speed (p=0.022). Obesity did not affect slip distance, slip duration or peak slip speed. Obese individuals also exhibited a higher rate of falls; 32% of obese individuals fell compared to 10% of non-obese (p=0.005). Obese individuals were more than eight times more likely to experience a fall than non-obese individuals when adjusting for age, gender and gait speed. No age effects were found for slip severity or slip outcome. These results, along with epidemiological data reporting higher fall rates among the obese, indicate that obesity may be a significant risk factor for experiencing slip-induced falls. Slip severity thresholds were also reported that may have value in developing controls for fall prevention.
Alternative measures of toe trajectory more accurately predict the probability of tripping than minimum toe clearance
Byju, Achu G.; Nussbaum, Maury A.; Madigan, Michael L. (Elsevier, 2016-12-08)
Tripping is responsible for a large percentage of falls. Minimum toe clearance (MTC) during the swing phase of gait is commonly used to infer the probability of tripping (POT). However, there is limited empirical evidence to support the relationship between these two variables, and other measures of toe trajectory may better predict POT than MTC. The goals of this study were to: 1) quantify the relationship between MTC and POT; and 2) explore alternative measures of toe trajectory that may predict POT more accurately than MTC. POT was estimated by comparing the distribution of tripping obstacles measured along heavily-used, paved sidewalks on a university campus, to the toe trajectory of 40 young adults obtained while walking over an obstacle-free walkway in a research laboratory. POT exhibited a curvilinear relationship with MTC, and regression equations were established to predict POT from MTC. POT was more accurately predicted when using virtual points on the bottom of the anterior edge of the shoe to determine MTC, compared to using a physical marker located on top of the toes to determine MTC. POT was also more accurately predicted when using a new measure of toe trajectory (the area below 40 mm and above the toe trajectory, normalized by the swing length), compared to just MTC. These are the first empirical results supporting a direct, quantitative relationship between MTC and POT. These results may improve the ability to identify risk factors that influence POT, and aid in developing interventions to reduce POT.
Age-related differences in muscle power during single-step balance recovery
Madigan, Michael L. (Human Kinetics, 2006-08-01)
The purpose of this study was to investigate age-related differences in muscle power during a surrogate task of trip recovery. Participants included 10 healthy young men (19-23 years old) and 10 healthy older men (65-83). The task involved releasing participants from a forward-leaning posture. After release, participants attempted to recover their balance using a single step of the right foot. Muscle power at the hip, knee, and ankle of the stepping limb were determined from the product of joint angular velocity and joint torque. Muscle powers during balance recovery followed a relatively consistent pattern in both young and older men, and showed effects of both lean and age. Interestingly, the effects of age did not always involve smaller peak power values in the older men as expected from the well-documented loss of muscle power with aging. Older men exhibited smaller peak muscle power at the knee and larger peak muscle power at the ankle and hip compared to young men. The increases in muscle power at the ankle and hip may result from a neuromuscular adaptation aimed at improving balance recovery ability by compensating for the age-related loss of muscle function. © 2006 Human Kinetics, Inc.
A Pilot Study Exploring Obesity-Related Differences in Fall Rate and Kinematic Response Resulting From a Laboratory-Induced Trip
Garman, Christina R.; Nussbaum, Maury A.; Franck, Christopher T.; Madigan, Michael L. (Taylor & Francis, 2016-08-15)
Background: Obese adults are reported to fall at a higher rate than non-obese adults. Purpose: To help determine the reason for this higher fall rate, we quantified fall rates, kinematics at trip onset, and kinematics during the response to a laboratory-induced trip among two groups of young adults with higher and lower body mass indexes (BMI) that approximated obese and healthy-weight ranges. Our focus was on young adults given that they comprise a substantial portion of the workforce. Methods: Twenty-one young adult subjects, including 10 with a lower BMI (19.4–25.7 kg/m2) and 11 with a higher BMI (29.8–42.9 kg/m2), walked along a 10 m walkway at a purposeful speed. During a randomly selected walking trial, an obstacle was raised to elicit a trip. Results: Among the 19 subjects who unambiguously fell or recovered, 30% of subjects with higher BMI fell and 0% of lower BMI subjects fell, but this difference did not reach statistical significance. Among the 15 subjects who used an elevating strategy, all recovered balance, and the only kinematic response variable that differed between BMI groups was that recovery step time was longer among the higher BMI group. Among the four subjects who used a lowering strategy, no statistical analysis was possible due to a small number of subjects, but several measures were consistent with a less favorable kinematic response among the three higher BMI fallers compared to the one lower BMI subject who recovered. Conclusions: This study provides preliminary evidence that obesity may adversely influence fall rate and recovery kinematics after tripping among young adults. Additional larger scale studies are needed to better understand contributing and modifiable factors that can be targeted via intervention.
A bootstrapping method to assess the influence of age, obesity, gender, and gait speed on probability of tripping as a function of obstacle height
Garman, Christina R.; Franck, Christopher T.; Nussbaum, Maury A.; Madigan, Michael L. (Elsevier, 2015-02-03)
Tripping is a common mechanism for inducing falls. The purpose of this study was to present a method that determines the probability of tripping over an unseen obstacle while avoiding the ambiguous situation wherein median minimum foot clearance (MFC) and MFC interquartile range concurrently increase or decrease, and determines how the probability of tripping varies with potential obstacle height. The method was used to investigate the effects of age, obesity, gender, and gait speed on the probability of tripping. MFC was measured while 80 participants walked along a 10-m walkway at self-selected and hurried gait speeds. The method was able to characterize the probability of tripping as a function of obstacle height, and identify effects of age, obesity, gender, and gait speed. More specifically, the probability of tripping was lower among older adults, higher among obese adults, higher among females, and higher at the slower self-selected speed. Many of these results were not found, or clear, from the more common approach on characterizing likelihood of tripping based on MFC measures of central tendency and variability.
A data-driven approach to classifying manual material handling tasks using markerless motion capture and recurrent neural networks
Ojelade, Aanuoluwapo; Rajabi, Mohammad Sadra; Kim, Sunwook; Nussbaum, Maury A. (Elsevier, 2025-05)
Work-related musculoskeletal disorders (WMSDs) are prevalent problems that encompass a range of conditions affecting muscles, tendons, and nerves due to repetitive strain, non-neutral postures, and forceful exertions. These disorders lead to pain, reduced productivity and substantial healthcare costs. Effective physical exposure assessment tools are needed in the workplace to quantify WMSD risks and the association between exposure and risks. While several tools are available, they are often limited in scope and lack the ability to assess physical risks continuously. In this study, we evaluated a data-driven approach to continuously classify manual material handling tasks and specific task conditions using different feature sets and machine learning algorithms. Specifically, kinematic data from markerless motion capture (MMC) system was used as input for various recurrent neural networks to classify among eight distinct manual material handling tasks: box lifting, asymmetric box lifting, box carriage, box pushing, box pulling, cart pushing, overhead lifting, and box lowering. The models we tested include bidirectional long-short term memory, gated recurrent units, and bidirectional gated recurrent units. We also classified specific task conditions, such as hand configurations and initial lifting height. Overall, using the MMC's kinematic data led to satisfactory results (e.g., accuracy of 80–94 %) in classifying the tasks and the task conditions. Our results, though, also emphasize that classification performance varied across different feature sets, tasks, and between males and females. Nonetheless, use of MMC demonstrates clear potential for physical exposure assessment.
Employing Eye Trackers to Reduce Nuisance Alarms
Herdt, Katherine; Hildebrandt, Michael; LeBlanc, Katya; Lau, Nathan (MDPI, 2025-04-22)
When process operators anticipate an alarm prior to its annunciation, that alarm loses information value and becomes a nuisance. This study investigated using eye trackers to measure and adjust the salience of alarms with three methods of gaze-based acknowledgement (GBA) of alarms that estimate operator anticipation. When these methods detected possible alarm anticipation, the alarm’s audio and visual salience was reduced. A total of 24 engineering students (male = 14, female = 10) aged between 18 and 45 were recruited to predict alarms and control a process parameter in three scenario types (parameter near threshold, trending, or fluctuating). The study evaluated whether behaviors of the monitored parameter affected how frequently the three GBA methods were utilized and whether reducing alarm salience improved control task performance. The results did not show significant task improvement with any GBA methods (F(3,69) = 1.357, p = 0.263, partial η² = 0.056). However, the scenario type affected which GBA method was more utilized (X² (2, N = 432) = 30.147, p < 0.001). Alarm prediction hits with gaze-based acknowledgements coincided more frequently than alarm prediction hits without gaze-based acknowledgements (X² (1, N = 432) = 23.802, p < 0.001, OR = 3.877, 95% CI 2.25–6.68, p < 0.05). Participant ratings indicated an overall preference for the three GBA methods over a standard alarm design (F(3,63) = 3.745, p = 0.015, partial η² = 0.151). This study provides empirical evidence for the potential of eye tracking in alarm management but highlights the need for additional research to increase validity for inferring alarm anticipation.
Passive back support exoskeletons do not effectively reduce physical demands during simulated floor tiling
Usmani, Ahmad Raza; Rajabi, Mohammad Sadra; Ojelade, Aanuoluwapo; Kim, Sunwook; Harris-Adamson, Carisa; Barr, Alan; Nussbaum, Maury A. (Elsevier, 2025-05)
Back-support exoskeletons (BSEs) have the potential to reduce physical demands during many occupational tasks, but their effectiveness in flooring work remains underexplored. Eighteen participants performed simulated floor tiling work under three intervention conditions (HeroWear Apex™ = HW, Laevo Flex™ = LV, and no device = ND), across two tile sizes (small vs. large), and two task types (tiling vs. grouting). HW use increased back muscle activation by ∼13-44 % compared to ND, while LV led to minimal changes. Some participants reported concerns with both BSEs, including movement restrictions, discomfort, and skin irritation. Significant interaction effects of intervention and tile size on muscle activity and subjective outcomes suggest the importance of considering task-specificity in BSE evaluations. Overall, the BSEs examined here did not effectively reduce physical demands during simulated floor tiling. Although we assessed BSE effects on tiling, our findings could also guide future implementation of exoskeletons in other similar construction tasks.
User Experiences and Adoption Factors for a Back-Support Exosuit in Automotive Logistics: Results from Field Testing up to 18 Months
Kim, Sunwook; Porto, Ryan; Nussbaum, Maury A. (Taylor & Francis, 2025-04)
Occupational Applications: We interviewed 24 automotive logistic workers who had used (or stopped using) a soft back-support exoskeleton (exosuit). These workers generally recognized potentially benefits of back-support exosuits, with 11 continuing use. Their use was primarily influenced by usability, compatibility, and comfort factors. We found wide variability in use patterns and adaptation periods, and that there were specific design concerns and concerns regarding thermal discomfort. To enhance long-term adoption of exosuits in industrial settings, organizations should consider: 1) implementing flexible, individualized training programs addressing specific usability challenges; 2) adopting a voluntary approach accommodating varied adaptation needs; 3) providing comprehensive education on potential health benefits; 4) using peer demonstrations to promote acceptance; and 5) collaborating with manufacturers to improve designs based on user feedback. These strategies may help enhance acceptance and sustained use of exosuits, potentially contributing to more effective support for occupational health during manual material handling tasks.
Vibrotactile feedback in virtual motor learning: A systematic review
Islam, Md Shafiqul; Lim, Sol (Elsevier, 2022-05-01)
Vibrotactile feedback can be effectively applied to motor (physical) learning in virtual environments, as it can provide task-intrinsic and augmented feedback to users, assisting them in enhancing their motor performance. This review investigates current uses of vibrotactile feedback systems in motor learning applications built upon virtual environments by systematically synthesizing 24 peer-reviewed studies. We aim to understand: (1) the current state of the science of using real-time vibrotactile feedback in virtual environments for aiding the acquisition (or improvement) of motor skills, (2) the effectiveness of using vibrotactile feedback in such applications, and (3) research gaps and opportunities in current technology. We used the Sensing-Analysis-Assessment-Intervention framework to assess the scientific literature in our review. The review identifies several research gaps in current studies, as well as potential design considerations that can improve vibrotactile feedback systems in virtual motor learning applications, including the selection and placement of feedback devices and feedback designs.
Real-time vibrotactile feedback system for reducing trunk flexion exposure during construction tasks
Lim, Sol; Yang, Xiang (Elsevier, 2023-07)
Workplaces are increasingly evaluating the use of wearables for ergonomic assessment and providing biofeedback as a real-time postural intervention to improve workers’ posture. However, the effectiveness of such intervention systems has yet to be thoroughly investigated in different types of industrial tasks. This study tested the immediate effects of using vibrotactile feedback in simulated construction work tasks including lifting-lowering, shoveling, and tying rebar, to investigate the potential for such an intervention as a way to instruct workers in reducing excessive trunk flexion exposures. Fourteen male participants completed simulated work tasks with three different feedback locations, namely, no feedback, back, and wrist. The results demonstrate that the 95th, 90th, and 50th percentiles of trunk flexion angles are significantly lower for lifting-lowering and shoveling tasks when the feedback system is used. No significant postural changes were observed for the rebar tying task at any combination of percentile and feedback location. The rating of perceived exertion (RPE) for each task did not differ significantly between feedback conditions. Productivity remained the same with the feedback for lifting-lowering and rebar tying, while it was significantly reduced (4.5% of working rate reduction) in shoveling. Participants rated the wrist as the most preferred feedback location. The results of this study suggest that vibrotactile feedback has potential as an effective postural intervention for ergonomic risk factors in selected construction work tasks. Implications for the future design of real-time wearable, sensor-based vibrotactile feedback systems for postural control intervention during dynamic work tasks are discussed.
Use of a wearable electromyography armband to detect lift-lower tasks and classify hand loads
Taori, Sakshi; Lim, Sol (Elsevier, 2024-09)
We used an armband with embedded surface electromyography (sEMG) electrodes, together with machine-learning (ML) models, to automatically detect lifting-lowering activities and classify hand loads. Nine healthy participants (4 male and 5 female) completed simulated lifting-lowering tasks in various conditions and with two different hand loads (2.3 and 6.8 kg). We compared three sEMG signal feature sets (i.e., time, frequency, and a combination of both domains) and three ML classifiers (i.e., Random Forest, Support Vector Machine, and Logistic Regression). Both Random Forest and Support Vector Machine models, using either time-domain or time- and frequency-domain features, yielded the best performance in detecting lifts, with respective accuracies of 79.2% (start) and 86.7% (end). Similarly, both ML models yielded the highest accuracy (80.9%) in classifying the two hand loads, regardless of the sEMG features used, emphasizing the potential of sEMG armbands for assessing exposure and risks in occupational lifting tasks.

Browse

Recent Submissions