Search Results (52)

Wheelchair-mounted assistive robotic manipulators can provide reach and grasp functions for power wheelchair users. This in-lab study evaluated a vision-guided shared control (VGS) system with twelve users completing two multi-step kitchen tasks: a drinking task and a popcorn making task. Using a mixed methods approach participants compared VGS and manual joystick control, providing performance metrics, qualitative insights, and lessons learned. Data collection included demographic questionnaires, the System Usability Scale (SUS), NASA Task Load Index (NASA-TLX), and exit interviews. No significant SUS differences were found between control modes, but NASA-TLX scores revealed VGS control significantly reduced workload during the drinking task and the popcorn task. VGS control reduced operation time and improved task success but was not universally preferred. Six participants preferred VGS, five preferred manual, and one had no preference. In addition, participants expressed interest in robotic arms for daily tasks and described two main operation challenges: distinguishing wrist orientation from rotation modes and managing depth perception. They also shared perspectives on how a personal robotic arm could complement caregiver support in their home. Full article

Background: Manual wheelchair propulsion is often associated with pain in the upper extremities. Recording spatio-temporal parameters can optimize movement patterns and prevent injuries. This study compares a marker-based camera system with inertial measurement units to validate their use in wheelchair propulsion on a test stand. Methods: Spatio-temporal parameters of 27 manual wheelchair users propelling at three self-selected speeds (slow, normal, fast) were simultaneously recorded using a marker-based camera system and inertial measurement units, and subsequently compared between both systems. Results: A high correlation was observed among all spatio-temporal parameters (ρ > 0.992). The biases for the start time of hand contact with the pushrim (−0.02 ± 0.02 s), hand release from the pushrim (−0.02 ± 0.01 s), and push length (−0.45 ± 21.45 ms) were slightly overestimated, while recovery length (0.54 ± 21.02 ms), cycle speed (2.37 ± 2.67°/s), and push angle (1.75 ± 4.14°) were slightly underestimated. No bias was found for propulsion frequency. Conclusions: The spatio-temporal parameters recorded using inertial measurement units are suitable for the evaluation of manual wheelchair propulsion and can be used in a clinical context. The low acquisition costs and simple installation process may increase the use of inertial measurement units in the future. Full article

An accurate assessment of sidewalk conditions is critical for ensuring compliance with the Americans with Disabilities Act (ADA), particularly to safeguard mobility for wheelchair users. This paper presents a novel 3D reconstruction framework based on neural radiance field (NeRF), which utilize a monocular video input from consumer-grade cameras to generate high-fidelity 3D models of sidewalk environments. The framework enables automatic extraction of ADA-relevant geometric features, including the running slope, the cross slope, and vertical displacements, facilitating an efficient and scalable compliance assessment process. A comparative study is conducted across three surveying methods—manual measurements, LiDAR scanning, and the proposed NeRF-based approach—evaluated on four sidewalks and one curb ramp. Each method was assessed based on accuracy, cost, time, level of automation, and scalability. The NeRF-based approach achieved high agreement with LiDAR-derived ground truth, delivering an F1 score of 96.52%, a precision of 96.74%, and a recall of 96.34% for ADA compliance classification. These results underscore the potential of NeRF to serve as a cost-effective, automated alternative to traditional and LiDAR-based methods, with sufficient precision for widespread deployment in municipal sidewalk audits. Full article

Manual wheelchair users are at high risk of upper limb overuse injuries due to repetitive propulsion mechanics. To address this, we developed a novel detachable push–pull dual-propulsion device that enables both forward and backward propulsion, aiming to reduce shoulder strain and promote balanced muscle engagement. This study presents a protocol to evaluate the device’s biomechanical impact and ergonomic effects, focusing on objective, quantitative analysis using a repeated-measures within-subject design. Thirty participants with spinal cord injury will perform standardized propulsion trials under two conditions: push and pull. Motion capture and surface electromyography (EMG) will assess upper limb kinematics and muscle activation. Each propulsion mode will be repeated over a 10-m track, and maximum voluntary contraction (MVC) data will be collected for EMG normalization. The protocol aims to provide objective evidence on the propulsion efficiency, muscle distribution, and ergonomic safety of the device. Findings will inform future assistive technology development and rehabilitation guidelines for manual wheelchair users. Full article

Background: Pressure injuries (PIs) and shoulder pain (SP) are frequent problems in individuals with spinal cord injury (SCI), affecting both quality of life and healthcare use. Although pressure relief (PR) is recommended to prevent PIs, it is often not performed regularly, and its long-term benefits remain unclear. Furthermore, some PR methods may contribute to SP, resulting in conflicting clinical guidelines. This study aims to objectively measure PR performance and investigate its long-term relationship with PI and SP. Methods: This study is a longitudinal observational study involving 70 manual wheelchair users with complete SCI. Over one year, participants attend five study visits to assess confounding factors such as comorbidities and shoulder range of motion. PR performance (technique, frequency, duration) is continuously monitored for three weeks after each of the first four visits using textile measurement mats, while SP is assessed weekly with a questionnaire. Causal associations with PI and SP will be examined using directed acyclic graphs and multivariable regression modelling. Results: The study is ongoing. Long-term objective data on PR performance will provide insights into its relationship with PI and SP. Conclusions: Findings will inform clinical practice and contribute to improved evidence-based PR guidelines for individuals with SCI. Full article

Background: Assessment of physical competencies is one way to enhance uptake and maintain participation in a leisure-time physical activity (LTPA) for manual wheelchair (MWC) users. Weineck’s model explains physical competencies through eight physical qualities. The use of this model may influence MWC users’ motivation for participation in LTPA. The aim of this study was to identify and categorize existing assessment tools designed for MWC users of physical qualities (strength, speed, power, muscular endurance, cardiovascular endurance, balance, and flexibility). Methods: A mapping review was conducted following the “Preferred reporting items for systematic reviews and meta-analyses (PRISMA)” guidelines. Two reviewers selected articles that documented assessment tools for the physical qualities of MWC users. Tools were extracted from each article to categorize them in a list. Results: A total of 149 articles that contained assessments of physical qualities were included in the review. A total of 97 assessment tools were extracted and categorized according to the eight physical qualities. Conclusions: These assessments are categorized into physical qualities that would facilitate the creation of test batteries aimed at assessing physical qualities in MWC users. This study is the first step in the construction of a test battery to assess the physical qualities of MWC users. Full article

A novel electromyography (EMG)-based wheelchair interface was developed that uses contractions from the temporalis muscle to control a wheelchair. To aid in the training process for users of this interface, a serious training game, Limbitless Journey, was developed to support patients. Amyotrophic Lateral Sclerosis (ALS) is a condition that causes progressive motor function loss, and while many people with ALS use wheelchairs as mobility devices, a traditional joystick-based wheelchair interface may become inaccessible as the condition progresses. Limbitless Journey simulates the wheelchair interface by utilizing the same temporalis muscle contractions for control of in-game movements, but in a low-stress learning environment. A usability study was conducted to evaluate the serious-game-based training platform. A major outcome of this study was qualitative data gathered through a concurrent think-aloud methodology. Three cohorts of five participants participated in the study. Audio recordings of participants using Limbitless Journey were transcribed, and a sentiment analysis was performed to evaluate user perspectives. The goal of the study was twofold: first, to perform a think-aloud usability study on the game; second, to determine whether accessible controls could be as effective as manual controls. The user comments were coded into the following categories: game environment, user interface interactions, and controller usability. The game environment category had the most positive comments, while the most negative comments were primarily related to usability challenges with the flexion-based controller. Interactions with the user interface were the main topic of feedback for improvement in future game versions. This game will be utilized in subsequent trials conducted at the facility to test its efficacy as a novel training system for the ALS population. The feedback collected will be implemented in future versions of the game to improve the training process. Full article

Background: Manual wheelchairs (MWCs) are critical assistive devices for individuals with spinal cord injury (SCI) and other mobility impairments. However, inconsistencies exist in evaluating usability across different manual wheelchair designs. Usability evaluation methods are essential to ensure optimal design and function. Methods: A systematic review following PRISMA guidelines was conducted. Databases searched included PubMed, ScienceDirect, and DBpia. A comprehensive search was completed up to April 2024. Keywords combined concepts such as “spinal cord injury”, “manual wheelchair”, and “usability evaluation” using Boolean operators (AND, OR) and truncation strategies. Results: From 2134 initial records, 30 studies met the inclusion criteria. Studies included individuals with SCI as the primary population, but also incorporated able-bodied participants when necessary to simulate conditions not feasible for SCI users. Evaluation methods included objective assessments (e.g., kinematics, kinetics, electromyography) and subjective measures (e.g., System Usability Scale, user interviews). Conclusions: This review highlights methodological trends in MWC usability testing and identifies key metrics to guide future research and design improvements. While the primary focus was on individuals with SCI, studies involving healthy participants were included where ethically or practically justified. Full article

Background: Prolonged manual wheelchair usage often leads to musculoskeletal disorders in the upper body of individuals with spinal cord injury (SCI) due to repetitive, unidirectional movements. To mitigate these issues, targeted exercise of the back muscles—particularly those involving pulling movements of the arms and shoulders—is recommended. Therefore, this study aimed to develop a detachable, two-way propulsion system for manual wheelchairs, enabling propulsion through both pushing forward and pulling backward on the wheelchair pushrims. Methods: The propulsion system was engineered using a planetary gear train to facilitate dual-direction propulsion. Specifically, the planetary gear reverses the rotational direction, allowing the wheelchair to advance forward even when users pull the pushrims backward. Thus, the wheelchair can move forward through either pushing forward or pulling backward actions. Results: A prototype of the proposed system was fabricated using 3D printing technology and its functionality was verified. The prototype successfully demonstrated the two-way propulsion capability and the operation of the attachment mechanism. Additionally, the pilot test confirmed that an individual with SCI was able to propel a manual wheelchair equipped with the two-way propulsion system using both propulsion methods and switch between the methods independently while maintaining stability and safety throughout the test. Conclusion: The developed detachable two-way propulsion system shows significant promise as both a mobility aid and an exercise device, potentially reducing musculoskeletal complications among individuals with SCI who regularly utilize manual wheelchairs. Full article

Traditional VO_2max testing methods are often impractical for manual wheelchair users, as they rely on lower-body exercise protocols, require specialized equipment, and trained personnel. The 6-Minute Push Test (6MPT) is a widely used cardiovascular assessment that may provide a feasible alternative for estimating aerobic capacity in this population. This study aimed to develop a predictive model for VO_2max using physiological variables recorded during the 6MPT. Twenty-eight participants (14 novice and 14 expert manual wheelchair users) completed the test while wearing a VO₂ mask and heart rate monitor. Spearman correlation analysis showed that distance covered during the 6MPT significantly correlated with VO_2max (r = 0.685, p < 0.001). A stepwise linear regression identified two predictive models: one using distance alone (R² = 0.416, p < 0.001) and another incorporating both distance and maximum heart rate (R² = 0.561, p < 0.001). These models offer practical estimations of VO_2max, eliminating separate protocols. Our findings suggest that the 6MPT can serve as a simple, cost-effective alternative to laboratory-based VO₂ testing, facilitating routine cardiovascular fitness assessments for manual wheelchair users in clinical and community settings. Future research should focus on validating these models in a larger, more diverse cohort to enhance their generalizability. Full article

Background: The aim was to explore independent wheeled mobility in children with CP, and identify predictors of early independent wheeled mobility and changes over time across birth cohorts. Methods: We included data from the Norwegian Quality and Surveillance Registry for Cerebral Palsy (NorCP) comprising 11,565 assessments of 1780 children born in 2002–2019. Variables included demographic data, Gross Motor Function Classification System (GMFCS) and Manual Ability Classification System (MACS) levels, wheelchair use, and independent wheeled mobility. Cox proportional hazard regression was used to identify predictors for early independent wheeled mobility. Kaplan–Meier survival curves were used to compare birth cohorts. Results: Of 769 (43%) children who used a wheelchair, 511 (67%) had independent wheeled mobility. Two thirds of the children (n = 337) achieved independent wheeled mobility before age 7. Most children with independent wheeled mobility used powered wheelchairs. Children at GMFCS levels III and IV were more likely to reach independent wheeled mobility at an early age. Children at MACS levels III–V had a lower probability of early independent wheeled mobility. The average age of achieving independent mobility decreased from 9.5 to 4.0 years between birth years 2002 and 2019. Conclusions: Two in three children were independent wheelchair users before 7 years of age, and the age of obtaining independent wheeled mobility has decreased over the last 20 years. Children with better hand function were more likely to obtain early independent wheeled mobility. Early intervention programs to promote mobility, development and participation should include powered mobility, adapted steering options, and interventions for hand function. Full article

Mobility is essential for individuals with physical disabilities, and wheelchairs significantly enhance their quality of life. Recent advancements focus on developing sophisticated control systems for effective and efficient interaction. This study evaluates the usability and performance of three wheelchair control modes manual, automatic, and voice controlled using a virtual reality (VR) simulation tool. VR provides a controlled and repeatable environment to assess navigation performance and motion sickness across three scenarios: supermarket, museum, and city. Twenty participants completed nine tests each, resulting in 180 trials. Findings revealed significant differences in navigation efficiency, distance, and collision rates across control modes and scenarios. Automatic control consistently achieved faster navigation times and fewer collisions, particularly in the supermarket. Manual control offered precision but required greater user effort. Voice control, while intuitive, resulted in longer distances traveled and higher collision rates in complex scenarios like the city. Motion sickness levels varied across scenarios, with higher discomfort reported in the city during voice and automatic control. Participant feedback, gathered via a Likert scale questionnaire, highlighted the potential of VR simulation for evaluating user comfort and performance. This research underscores the advantages of VR-based testing for rapid prototyping and user-centered design, offering valuable insights into improving wheelchair control systems. Future work will explore adaptive algorithms to enhance usability and accessibility in real world applications. Full article

Manual wheelchair users (MWUs) frequently report shoulder problems and have a three-times-higher likelihood of rotator cuff pathology compared to able-bodied individuals. Shoulder health is crucial for MWU independence, their social participation, and quality of life. Daily activities such as wheelchair propulsion potentially lead to fatigue and overload. Since comprehensive data are limited, this study aimed to implement a wheelchair mobility metrics (WCMM) method to examine various aspects of wheelchair use in daily life. Two inertial measurement units (IMUs) were placed on the wheelchair frame and wheel of 19 participants with a spinal cord injury (SCI). WCMMs like distance covered, number of pushes and turns, and incline were derived from real-life measurements and normalized to a period of 8 h. Large variation was observed among participants. The distance covered ranged from 0.5 to 10.7 km, with the number of pushes from 438 to 4820. The number of turns ranged from 269 to 1396, and the average distance per mobility bout from 5 to 59 m. This wide variation over participants emphasizes the importance of data-driven clinical decision making and patient education. Further studies with larger samples and duration are needed to fully understand MWUs’ mobility patterns and their implications for shoulder health. Full article

The increasing number of individuals with disabilities—over 61 million adults in the United States alone—underscores the urgent need for technologies that enhance autonomy and independence. Among these individuals, millions rely on wheelchairs and often require assistance from another person with activities of daily living (ADLs), such as eating, grooming, and dressing. Wheelchair-mounted assistive robotic arms offer a promising solution to enhance independence, but their complex control interfaces can be challenging for users. Automating control through deep learning-based object detection models presents a viable pathway to simplify operation, yet progress is impeded by the absence of specialized datasets tailored for ADL objects suitable for robotic manipulation in home environments. To bridge this gap, we present a novel ADL object dataset explicitly designed for training deep learning models in assistive robotic applications. We curated over 112,000 high-quality images from four major open-source datasets—COCO, Open Images, LVIS, and Roboflow Universe—focusing on objects pertinent to daily living tasks. Annotations were standardized to the YOLO Darknet format, and data quality was enhanced through a rigorous filtering process involving a pre-trained YOLOv5x model and manual validation. Our dataset provides a valuable resource that facilitates the development of more effective and user-friendly semi-autonomous control systems for assistive robots. By offering a focused collection of ADL-related objects, we aim to advance assistive technologies that empower individuals with mobility impairments, addressing a pressing societal need and laying the foundation for future innovations in human–robot interaction within home settings. Full article

Self-propelled manual wheelchairs offer several advantages over electric wheelchairs, including promoting physical activity and requiring less maintenance due to their simple design. While theoretical analyses provide valuable insights, laboratory testing remains the most reliable method for evaluating and improving the efficiency of manual wheelchair drives. This article reviews and analyzes the laboratory methods for assessing the efficiency of wheelchair propulsion documented in the scientific literature: (1) A wheelchair dynamometer that replicates real-world driving scenarios, quantifies the wheelchair’s motion characteristics, and evaluates the physical exertion required for propulsion. (2) Simultaneous measurements of body position, motion, and upper limb EMG data to analyze biomechanics. (3) A method for determining the wheelchair’s trajectory based on data from the dynamometer. (4) Measurements of the dynamic center of mass (COM) of the human–wheelchair system to assess stability and efficiency; and (5) data analysis techniques for parameterizing large datasets and determining the COM. The key takeaways include the following: (1) manual wheelchairs offer benefits over electric ones but require customization to suit individual user biomechanics; (2) the necessity of laboratory-based ergometer testing for optimizing propulsion efficiency and safety; (3) the feasibility of replicating real-world driving scenarios in laboratory settings; and (4) the importance of efficient data analysis techniques for interpreting biomechanical studies. Full article