scholarly journals Usability and performance validation of an ultra-lightweight and versatile untethered robotic ankle exoskeleton

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Greg Orekhov ◽  
Ying Fang ◽  
Chance F. Cuddeback ◽  
Zachary F. Lerner
Keyword(s):  
Body Mass ◽  
Perceived Exertion ◽  
Setup Time ◽  
Setup Times ◽  
Metabolic Power ◽  
System Usability Scale ◽  
Wide Range ◽  
System Usability ◽  
Improved Performance ◽  
Ankle Exoskeleton

Abstract Background Ankle exoskeletons can improve walking mechanics and energetics, but few untethered devices have demonstrated improved performance and usability across a wide range of users and terrains. Our goal was to design and validate a lightweight untethered ankle exoskeleton that was effective across moderate-to-high intensity ambulation in children through adults with and without walking impairment. Methods Following benchtop validation of custom hardware, we assessed the group-level improvements in walking economy while wearing the device in a diverse unimpaired cohort (n = 6, body mass = 42–92 kg). We also conducted a maximal exertion experiment on a stair stepping machine in a small cohort of individuals with cerebral palsy (CP, n = 5, age = 11–33 years, GMFCS I-III, body mass = 40–71 kg). Device usability metrics (device don and setup times and System Usability Score) were assessed in both cohorts. Results There was a 9.9 ± 2.6% (p = 0.012, range = 0–18%) reduction in metabolic power during exoskeleton-assisted inclined walking compared to no device in the unimpaired cohort. The cohort with CP was able to ascend 38.4 ± 23.6% (p = 0.013, range = 3–132%) more floors compared to no device without increasing metabolic power (p = 0.49) or perceived exertion (p = 0.50). Users with CP had mean device don and setup times of 3.5 ± 0.7 min and 28 ± 6 s, respectively. Unimpaired users had a mean don time of 1.5 ± 0.2 min and setup time of 14 ± 1 s. The average exoskeleton score on the System Usability Scale was 81.8 ± 8.4 (“excellent”). Conclusions Our battery-powered ankle exoskeleton was easy to use for our participants, with initial evidence supporting effectiveness across different terrains for unimpaired adults, and children and adults with CP. Trial registration Prospectively registered at ClinicalTrials.gov (NCT04119063) on October 8, 2019.

Exertional Hyponatremia and Serum Sodium Change During Ultraendurance Cycling

2017 ◽  
Vol 27 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Lawrence E. Armstrong ◽  
Elaine C. Lee ◽  
Douglas J. Casa ◽  
Evan C. Johnson ◽  
Matthew S. Ganio ◽  
...  
Keyword(s):  
Body Mass ◽  
Perceived Exertion ◽  
Thermal Sensation ◽  
Case Reports ◽  
Dietary Sodium ◽  
Muscle Cramp ◽  
Control Group ◽  
Post Exercise ◽  
Wide Range ◽  
Exertional Hyponatremia

Introduction:Exertional hyponatremia (EH) during prolonged exercise involves all avenues of fluid-electrolyte gain and loss. Although previous research implicates retention of excess fluid, EH may involve either loss, gain, or no change of body mass. Thus, the etiology, predisposing factors, and recommendations for prevention are vague—except for advice to avoid excessive drinking.Purpose:This retrospective field study presents case reports of two unacquainted recreational cyclists (LC, 31y and AM, 39 years) who began exercise with normal serum electrolytes but finished a summer 164-km ride (ambient, 34±5°C) with a serum [Na+] of 130 mmol/L.Methods:To clarify the etiology of EH, their pre- and post-exercise measurements were compared to a control group (CON) of 31 normonatremic cyclists (mean ± SD; 37±6 years; 141±3 mmol Na+/L).Results:Anthropomorphic characteristics, exercise time, and post-exercise ratings of thermal sensation, perceived exertion and muscle cramp were similar for LC, AM and CON. These two hyponatremic cyclists consumed a large and similar volume of fluid (191 and 189 ml/kg), experienced an 11 mmol/L decrease of serum [Na+], reported low thirst sensations; however, LC gained 3.1 kg (+4.3% of body mass) during 8.9 hr of exercise and AM maintained body mass (+0.1kg, +0.1%, 10.6h). In the entire cohort (n = 33), post-event serum [Na+] was strongly correlated with total fluid intake (R2 = 0.45, p < .0001), and correlated moderately with dietary sodium intake (R2=0.28, p = .004) and body mass change (R2 = 0.22, p = .02). Linear regression analyses predicted the threshold of EH onset (<135 mmol Na+/L) as 168 ml fluid/kg.Conclusions:The wide range of serum [Na+] changes (+6 to -11 mmol/L) led us to recommend an individualized rehydration plan to athletes because the interactions of factors were complex and idiosyncratic.

Pengujian Usability Website Pondok Pesantren Qodratullah Menggunakan System Usability Scale

2020 ◽  
Vol 6 (1) ◽  
pp. 34-43
Author(s):  
Fitri Purwaningtias ◽  
Usman Ependi
Keyword(s):  
Evaluation Process ◽  
Boarding School ◽  
Educational Institutions ◽  
Prospective Students ◽  
A Value ◽  
System Usability Scale ◽  
System Usability ◽  
Grade Scale ◽  
Final Score ◽  
Group B

Website saat ini telah digunakan diberbagai jenis instansi termasuk instansi pendidikan seperti Pondok Pesantren Qodratullah. Saat ini website Pondok Pesantren Qodratullah menjadi tulang punggung dalam penyebaran informasi terkain pondok pesantren kepada wali santri, alumni, calon santri dan masyarakat luas. Mengingat pentingnya website bagi Pondok Pesantren Qodratullah maka perlu untuk dilakukan evaluasi apakah informasi yang diberikan dan website yang ada telah memiliki nilai kebergunaan bagi pengguna atau tidak. Untuk itu di dalam penelitian ini dilakukan evaluasi untuk melihat perspektif pengguna terhadap website. Prose evaluasi dilakukan dengan system usability scale dengan sepuluh instrumen sebagai pernyataan evaluasi. Hasil evaluasi menunjukkan bahwa website Pondok Pesantren Qodratullah mendapatkan nilai akhir 88. Nilai 88 berarti website Pondok Pesantren Qodratullah mendapatkan adjective rating yang excellence, grade scale tergolong kelompok B dan tingkat acceptability termasuk acceptable. The website is currently used in various types of institutions including educational institutions such as Qodratullah Islamic Boarding School. Currently the Qodratullah Islamic Boarding School website is the backbone in the dissemination of information about Islamic boarding schools to the guardians of students, alumni, prospective students and the wider community. Considering the importance of the website for the Qodratullah Islamic Boarding School, it is necessary to evaluate whether the information provided, and the existing website have a useful value for the user or not. For this reason, in this study an evaluation was conducted to see the user's perspective on the website. The evaluation process is carried out with a system usability scale with ten instruments as evaluation statements. Evaluation results show that the Qodratullah Islamic Boarding School website gets a final score of 88. A value of 88 means that the Qodratullah Islamic Boarding School website gets an adjective rating that excellence, grade scale belongs to group B and the level of acceptability is acceptable

scholarly journals Caffeine improves biochemical and specific performance after judo training: a double-blind crossover study in a real judo training situation

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Kelvin Euton Oliveira Carmo ◽  
Diego Ignácio Valenzuela Pérez ◽  
Charles Nardelli Valido ◽  
Jymmys Lopes dos Santos ◽  
Bianca Miarka ◽  
...  
Keyword(s):  
Heart Rate ◽  
Uric Acid ◽  
Body Mass ◽  
Perceived Exertion ◽  
Rating Of Perceived Exertion ◽  
Power Performance ◽  
Double Blind ◽  
Biochemical Effect ◽  
Plasma Uric Acid ◽  
Hemodynamic Variables

Abstract Background Nutritional ergogenic aids are foods or nutrients that can improve physical performance. Among these foods with ergogenic properties, caffeine has shown that it can increase the fat catabolism, strength, and improve the cognition and time reaction of an athlete, therefore, it is hoped that it can improve the performance of judokas. This study through a double-blind crossover (supplement X placebo) protocol, investigated the effects caffeine supplementation (single capsule containing 5 mg/kg body mass intake 60 min before the session) on biochemical, anthropometrical, physical, subjective and hemodynamic variables measured before, during and after two typical judo trainingcxs sessions (120-min: 40-min of gymnastics; 40-min of specific technics and; 40-min of judo combat). Methods 8 high-level athletes (21.4 ± 2.0 years; 83.6 ± 15.2 kg; 1.8 ± 0.1 m; 17.9 ± 7.0 Fat%) were evaluated before and after each training for body mass, hydration, upper and lower limb power, performance in the special judo fitness test (SJFT), free fatty acids (FFA) in plasma, uric acid, glucose, lactate, heart rate, and pain. In addition, heart rate, FFA in plasma, uric acid, glucose, lactate, rating of perceived exertion and pain were assessed during the training. Results At 120 min, supplementation resulted in a higher concentration of plasma FFA (1.5 ± 0.5 vs. 1.0 ± 0.3 mmol/L; p = 0.047) and lactate (4.9 ± 1.8 vs. 3.0 ± 1.2 mmol/L; p = 0.047), and a lower concentration of uric acid (5.4 ± 0.9 vs. 7.0 ± 1.5 mg/dL; p = 0.04). Supplementation also resulted in performance maintenance (fatigue index) in the SJFT (Δ0.3 ± 2.0 vs Δ1.7 ± 2.5, for caffeine and placebo respectively, p = 0.046). No adverse effects were observed. Conclusion Based on the applied dose, intake time, and sample of this study, we can conclude that caffeine produces an ergogenic biochemical effect, and improves performance in judo athletes.

scholarly journals Effects of Congested Fixture on Men’s Volleyball Load Demands: Interactions with Sets Played

2021 ◽  
Vol 6 (2) ◽  
pp. 53
Author(s):  
Ricardo Lima ◽  
Henrique de Oliveira Castro ◽  
José Afonso ◽  
Gustavo De Conti Teixeira Costa ◽  
Sérgio Matos ◽  
...  
Keyword(s):  
Body Mass ◽  
Research Design ◽  
External Load ◽  
Significant Interaction ◽  
Perceived Exertion ◽  
Jump Height ◽  
Internal Load ◽  
Mixed Anova ◽  
Notational Analysis ◽  
Competitive Games

The purpose of this study was to compare the external load, internal load, and technical efficacy between the first and the second matches (M1 and M2) occurring in congested fixtures (two matches in two days) using the number of sets as a moderating factor. An observational analytic research design was adopted. Data from official volleyball matches were collected during the first competitive period of the championship, comprising 14 competitive games within 10 weeks. Ten male elite volleyball athletes (age: 21.7 ± 4.19 years of age; experience: 6.2 ± 3.8 years; body mass: 85.7 ± 8.69 kg; height: 192.4 ± 6.25 cm; BMI: 23.1 ± 1.40 kg/m2) participated in this study. Players were monitored for external load (number of jumps and height of jumps) and internal load (using the rate of perceived exertion—RPE). Additionally, notational analysis collected information about attack efficacy and receptions made during matches. The mixed ANOVA revealed no significant interaction between time (M1 vs. M2) and number of sets for number of jumps per minute (p = 0.235; ηp2 = 0.114), mean jump height (p = 0.076; ηp2 = 0.193), RPE (p = 0.261; ηp2 = 0.106), attack efficacy (p = 0.346; ηp2 = 0.085), Positive reception (p = 0.980; ηp2 = 0.002) and Perfect reception (p = 0.762; ηp2 = 0.022). In conclusion, congested fixtures do not seem to affect the performance of volleyball players negatively.

scholarly journals Comparison of the validity, perceived usefulness and usability of I-MeDeSA and TEMAS, two tools to evaluate alert system usability: a study protocol

BMJ Open ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. e050448
Author(s):  
Romaric Marcilly ◽  
Wu Yi Zheng ◽  
Regis Beuscart ◽  
Melissa T Baysari
Keyword(s):  
Human Factors ◽  
Convergent Validity ◽  
Perceived Usefulness ◽  
Decision Makers ◽  
Free Text ◽  
Alert System ◽  
System Usability Scale ◽  
System Usability ◽  
Ethical Approval ◽  
Alerting Systems

IntroductionResearch has shown that improvements to the usability of medication alert systems are needed. For designers and decisions-makers to assess usability of their alert systems, two paper-based tools are currently available: the instrument for evaluating human-factors principles in medication-related decision support alerts (I-MeDeSA) and the tool for evaluating medication alerting systems (TEMAS). This study aims to compare the validity, usability and usefulness of both tools to identify their strengths and limitations and assist designers and decision-makers in making an informed decision about which tool is most suitable for assessing their current or prospective system.Methods and analysisFirst, TEMAS and I-MeDeSA will be translated into French. This translation will be validated by three experts in human factors. Then, in 12 French hospitals with a medication alert system in place, staff with expertise in the system will evaluate their alert system using the two tools successively. After the use of each tool, participants will be asked to fill in the System Usability Scale (SUS) and complete a survey on the understandability and perceived usefulness of each tool. Following the completion of both assessments, participants will be asked to nominate their preferred tool and relay their opinions on the tools. The design philosophy of TEMAS and I-MeDeSA differs on the calculation of a score, impacting the way the comparison between the tools can be performed. Convergent validity will be evaluated by matching the items of the two tools with respect to the usability dimensions they assess. SUS scores and answers to the survey will be statistically compared for I-MeDeSA and TEMAS to identify differences. Free-text responses in surveys will be analysed using an inductive approach.Ethics and disseminationEthical approval is not required in France for a study of this nature. The results will be published in a peer-reviewed journal.

The Relation of the Perceptions of Aesthetics and Usability

2020 ◽  
Vol 64 (1) ◽  
pp. 1876-1880
Author(s):  
Dahlia Alharoon ◽  
Douglas J. Gillan
Keyword(s):  
Product Design ◽  
Research Study ◽  
System Usability Scale ◽  
System Usability ◽  
Perceived Usability

Aesthetics and usability both play critical roles in product design. But how might measurement of these two conceptually-different features of products interfere with one another? The current research study examines the effect of differences in aesthetics on perceived usability. Participants completed three tasks on a simulated website with a low usability interface. One group of participants used an interface with high aesthetics, whereas a second group interacted with an interface with poor aesthetics. Both groups rated the usability and aesthetics of the interface after completing the tasks. The aesthetics manipulation was effective in that the high aesthetics group provided higher ratings on two aesthetics scales than did the low aesthetics group; however, differences in aesthetics had no significant effect on usability as measured by the System Usability Scale (SUS). These findings support the idea that users make independent judgments of usability and aesthetics.

scholarly journals Increasing Usability of Homecare Applications for Older Adults: A Case Study

Designs ◽  
2019 ◽  
Vol 3 (2) ◽  
pp. 23 ◽  
Author(s):  
Christos Panagopoulos ◽  
Andreas Menychtas ◽  
Panayiotis Tsanakas ◽  
Ilias Maglogiannis
Keyword(s):  
Emergency Response ◽  
Independent Living ◽  
The Elderly ◽  
Usability Assessment ◽  
Technological Advances ◽  
System Usability Scale ◽  
System Usability ◽  
Practical Guidelines ◽  
Depth Interviews

As the world’s population is ageing, the field dealing with technology adoption by seniors has made headway in the scientific community. Recent technological advances have enabled the development of intelligent homecare systems that support seniors’ independent living and allow monitoring of their health status. However, despite the amount of research to understand the requirements of systems designed for the elderly, there are still unresolved usability issues that often prevent seniors from enjoying the benefits that modern ICT technologies may offer. This work presents a usability assessment of “HeartAround”, an integrated homecare solution incorporating communication functionalities, as well as health monitoring and emergency response features. An assessment with the system usability scale (SUS) method, along with in-depth interviews and qualitative analysis, has provided valuable insights for designing homecare systems for seniors, and validated some effective practical guidelines.

scholarly journals Body mass index as a measure of body fatness: age- and sex-specific prediction formulas

1991 ◽  
Vol 65 (2) ◽  
pp. 105-114 ◽  
Author(s):  
Paul Deurenberg ◽  
Jan A. Weststrate ◽  
Jaap C. Seidell
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Body Fat ◽  
Prediction Error ◽  
Bioelectrical Impedance ◽  
Skinfold Thickness ◽  
Fat Percentage ◽  
Wide Range ◽  
The Relationship ◽  
Age And Sex

In 1229 subjects, 521 males and 708 females, with a wide range in body mass index (BMI; 13.9–40.9 kg/m2), and an age range of 7–83 years, body composition was determined by densitometry and anthropometry. The relationship between densitometrically-determined body fat percentage (BF%) and BMI, taking age and sex (males =1, females = 0) into account, was analysed. For children aged 15 years and younger, the relationship differed from that in adults, due to the height-related increase in BMI in children. In children the BF% could be predicted by the formula BF% = 1.51xBMI–0.70xage–3.6xsex+1.4 (R2 0.38, SE of estimate (see) 4.4% BF%). In adults the prediction formula was: BF% = 1.20xBMI+0.23xage−10.8xsex–5.4 (R2 0.79, see = 4.1% BF%). Internal and external cross-validation of the prediction formulas showed that they gave valid estimates of body fat in males and females at all ages. In obese subjects however, the prediction formulas slightly overestimated the BF%. The prediction error is comparable to the prediction error obtained with other methods of estimating BF%, such as skinfold thickness measurements or bioelectrical impedance.

Evaluasi Usability pada Aplikasi Mobile ACC.ONE menggunakan System Usability Scale (SUS) dan Usability Testing

2021 ◽  
Vol 7 (1) ◽  
pp. 1-10
Author(s):  
Veni Manik ◽  
Clara Hetty Primasari ◽  
Yohanes Priadi Wibisono ◽  
Aloysius Bagas Pradipta Irianto
Keyword(s):  
Usability Testing ◽  
Low Grade ◽  
Percentile Rank ◽  
System Usability Scale ◽  
System Usability ◽  
Grade Scale

Perusahaan pembiayaan kendaraan mobil saat ini semakin banyak dan berkembang begitu pesat. Setiap perusahaan berusaha untuk menarik perhatian pelanggan dengan berbagai cara, terutama peningkatan teknologi untuk mendukung dan memudahkan proses kegiatan pembiayaan mobil. Perusahaan Astra Credit Company memanfaatkan teknologi dengan menyediakan aplikasi mobile acc.one yang dapat digunakan oleh pelanggan untuk membantu segala kegiatan proses pembiayaan mobil di Perusahaan ACC. Namun aplikasi ini terdapat beberapa masalah yang dapat diketahui dari ulasan pengguna di play store seperti aplikasi tiba-tiba error, aplikasi tidak dapat dibuka, fitur tidak berfungsi dengan semestinya, dll. Sehingga dilakukan pengujian aplikasi untuk mengetahui tingkat usability aplikasi dengan menggunakan metode system usability scale dan usability testing untuk mengetahui pengalaman pengguna. Hasil yang diperoleh tingkat usability aplikasi dengan tingkat kemudahan sebesar 73,33% yang masuk dalam kategori buruk, tingkat kecepatan pengguna sebesar 0,0467 goals/sec yang termasuk kategori normal, tingkat kesalahan pengguna sebesar 0,1230 total defect yang masuk dalam kategori kecil, dan tingkat kepuasan pengguna menggunakan kuesioner SUS memperoleh rerata SUS sebesar 54,45945946 yang artinya tingkat kepuasan pengguna rendah terhadap aplikasi berdasarkan penentuan nilai SUS yaitu Acceptability atau tingkat penerimaan penggunaan masuk dalam kategori marginal low, Grade Scale atau tingkat grade skala masuk dalam kategori F dan Adjective Rating masuk dalam kategori OK. Selain itu, pada SUS skor percentile rank masuk kedalam grade D.

Sign in / Sign up

Export Citation Format

Share Document