Gesture-Controlled Robotic Arm for Agricultural Harvesting Using a Data Glove with Bending Sensor and OptiTrack Systems.

This paper presents a gesture-controlled robotic arm system designed for agricultural harvesting, utilizing a data glove equipped with bending sensors and OptiTrack systems. The system aims to address the challenges of labor-intensive fruit harvesting by providing a user-friendly and efficient solution. The data glove captures hand gestures and movements using bending sensors and reflective markers, while the OptiTrack system ensures high-precision spatial tracking. Machine learning algorithms, specifically a CNN+BiLSTM model, are employed to accurately recognize hand gestures and control the robotic arm. Experimental results demonstrate the system's high precision in replicating hand movements, with a Euclidean Distance of 0.0131 m and a Root Mean Square Error (RMSE) of 0.0095 m, in addition to robust gesture recognition accuracy, with an overall accuracy of 96.43%. This hybrid approach combines the adaptability and speed of semi-automated systems with the precision and usability of fully automated systems, offering a promising solution for sustainable and labor-efficient agricultural practices.

Proposal for a new statistical procedure for the ergonomic design of furniture: implications of a protocol developed from measurements of a young population.

The current approach to the ergonomic design of furniture often relies on a gender-based segmentation, assuming that it yields homogeneous groups. However, this assumption has proved to be inconsistent in various contexts, particularly in regions characterized by ethnic diversity and economic inequalities, leading to diverse anthropometric characteristics. Considering gender alone fails to encompass this heterogeneity. The proposed approach introduces an 'anthropometric segmentation' methodology in which the population is clustered based on a wide range of anthropometric dimensions. Additionally, kernel density estimation is used when normality is not fulfilled. This step is critical, as it informs furniture dimensions by using selected percentiles from these density functions. The proposed approach is applied to a dataset of university students in Peru, a country marked by significant heterogeneity within its male and female populations. Ultimately, our methodology promises to improve the ergonomic design of furniture by accounting for a broader spectrum of anthropometric diversity.

Designing an adjustable ergonomic laptop desk and its evaluating by RULA and NERPA methods.

BACKGROUND: Using a computer may lead to pain in wrists, neck, and back. In addition, adopting various body postures like sitting cross-legged, semi-fowler's position, and putting the laptop on the leg may lead to the development of persistent and irreversible discomfort. OBJECTIVE: The purpose of this research is to design and build an adjustable ergonomic laptop desk based on the anthropometric characteristics of students in the age range of 20 to 30 years and to evaluate its efficiency using RULA and NERPA methods. METHODS: This cross-sectional study conducted on 108 students, in which an adjustable and portable ergonomic desk designed and built based on 10 anthropometric dimensions of students and the length and width of 10 different laptop models. Two assessment methods, RULA and NERPA, were used. Wilcoxon statistic test and SPSS version 26 software used for data analysis. RESULTS: The dimensions of the desk were calculated in three positions, and the desk was made with the ability to adjust height, width and tilt, each with two degrees of freedom. The statistical analysis comparing score of RULA and NERPA in two situations without using a desk and using an ergonomic laptop desk had a significant difference (P-value <  0.001). Comparison of RULA and NERPA scores showed that NERPA evaluated the low ergonomic risk level better than RULA method. CONCLUSIONS: Due to the ability to adjust the designed desk, the changes in RULA and NERPA score in all three modes, it indicates the effectiveness of the table in improving the body posture of users when using a laptop.

A systematic review of camera monitor system display layout designs: Integration of existing knowledge.

Despite the growing interest in mirrorless vehicles equipped with a camera monitor system (CMS), the human factors research findings on CMS display layout design have not been synthesized yet, hindering the application of the knowledge and the identification of future research directions. In an effort to address the 'lack of integration of the existing knowledge', this literature review addresses the following research questions: 1) what CMS display layout designs have been considered/developed by academic researchers and by automakers, respectively?; 2) among possible CMS display layout design alternatives, which ones have not yet been examined through human factors evaluation studies?; and 3) how do the existing human factors studies on the evaluation of different CMS display layout designs vary in the specifics of research? This review provides significant implications for the ergonomic design of CMS display layouts, including some potential design opportunities and future research directions.

Using a quantitative assessment of propulsion biomechanics in wheelchair racing to guide the design of personalized gloves: a case study.

This study with a T-52 class wheelchair racing athlete aimed to combine quantitative biomechanical measurements to the athlete's perception to design and test different prototypes of a new kind of rigid gloves. Three personalized rigid gloves with various, fixed wrist extension angles were prototyped and tested on a treadmill in a biomechanics laboratory. The prototype with 45° wrist extension was the athlete's favourite as it reduced his perception of effort. Biomechanical assessment and user-experience data indicated that his favourite prototype increased wrist stability throughout the propulsion cycle while maintaining a very similar propulsion technique to the athlete's prior soft gloves. Moreover, the inclusion of an innovative attachment system on the new gloves allowed the athlete to put his gloves on by himself, eliminating the need for external assistance and thus significantly increasing his autonomy. This multidisciplinary approach helped to prototype and develop a new rigid personalized gloves concept and is clearly a promising avenue to tailor adaptive sports equipment to an athlete's needs.

Design of Innovative Clothing for Pressure Injury Prevention: End-User Evaluation in a Mixed-Methods Study.

The global relevance of pressure injury (PI) prevention technologies arise from their impact on the quality of life of people with limited mobility and the costs associated with treating these preventable injuries. The purpose of this mixed methods study is to evaluate the design of a prototype integrating Smart Health Textiles for PI prevention based on feedback from specialist nurses who care for individuals who are prone to or have PIs. This is a mixed methods study. A structured questionnaire was conducted as part of an evaluation of a prototype garment for the prevention of PIs. This questionnaire was applied during the evaluation of the prototype and afterwards focus group discussions were held with experts. Descriptive statistics techniques were used to analyze the data and thematic and integrated content analysis was conducted through concomitant triangulation. Nineteen nurses took part, aged 30 to 39 years (52.6%) and with 12.31 ± 8.96 years of experience. Participants showed that the prototype required more manipulation and physical effort, which interfered its usefulness, in addition to presenting difficulties with the openings and the material of the closure system, which interfered with the ease of use and learning. Overall satisfaction with the product was moderate, with some areas for improvement found, such as satisfaction, recommendations to colleagues, and pleasantness of use. It is concluded that areas for improvement have been found in all dimensions, including in the design of openings and the choice of materials. These findings supply significant insights for improving clothing to meet the needs of healthcare professionals and patients.

Applying the quick exposure check in the workstation design process, physical and virtual prototype assessment.

BACKGROUND: The Quick Exposure Check (QEC) assesses four major body parts and engages users in assessing some physical interactions relevant to design in task analysis. OBJECTIVE: In this paper, we investigated the application of QEC as the ergonomic intervention to detect pre-production ergonomic design faults in the apple sorting machine by applying physical and virtual prototyping for three different tasks analysis divided into two phases (Task 1: Apple harvesting and preparation for sorting; Task 2: Sorting control and separation of waste fruits; Task 3: Transfer of separated apples). METHOD: First, the QEC questionnaire was administered while Iranian participants interacted with the machine to detect abnormal posture. Second, we redesigned a concept of the machine and assessed it with QEC by a focus group. RESULTS: Before design, the high pressure in Task 1 is on the back (dynamic), shoulder/arm, and very high pressure in Task 2, and in Task 3 on the back (static), arm/shoulder/neck, making an uncomfortable situation for posture. After redesign, we observed decreased pressures on the back/shoulder/arm in Task 1 from high to medium, in Task 3 from very high to low, and also in Task 2, this was detectable decreasing from very high pressures on the back/shoulder/arm and the high pressures on the neck to medium. CONCLUSION: Prototyping with QEC demonstrated that accurate redesigning of the machine with concentration on shifting from static tasks to dynamic or conversely, and ease of access by adjusting dimensions according to anthropometry and auxiliary products, could reduce musculoskeletal disorders.

Development of a Hip Joint Socket by Finite-Element-Based Analysis for Mechanical Assessment.

This article evaluates a hip joint socket design by finite element method (FEM). The study was based on the needs and characteristics of a patient with an oncological amputation; however, the solution and the presented method may be generalized for patients with similar conditions. The research aimed to solve a generalized problem, taking a typical case from the study area as a reference. Data were collected on the use of the current improving prosthesis-specifically in interaction with its socket-to obtain information on the new approach design: this step constituted the work's starting point, where the problems to be solved in conventional designs were revealed. Currently, the development of this type of support does not consider the functionality and comfort of the patient. Research has reported that 58% of patients with sockets have rejected their use, because they do not fit comfortably and functionally; therefore, patients' low acceptance or rejection of the use of the prosthesis socket has been documented. In this study, different designs were evaluated, based on the FEM as scientific support for the results obtained, for the development of a new ergonomic fit with a 60% increase in patient compliance, that had correct gait performance when correcting postures, improved fit-user interaction, and that presented an esthetic fit that met the usability factor. The validation of the results was carried out through the physical construction of the prototype. The research showed how the finite element method improved the design, analyzing the structural behavioral, and that it could reduce cost and time instead of generating several prototypes.

Design and ergonomic evaluation of a new adapted endoscope holder to reduce muscle pressure and discomfort during endoscopy.

BACKGROUND: Laparoscopic surgeons who regularly perform endoscopy are more likely to develop musculoskeletal disorders than other internal medicine specialists, a difference that attributed to repetitive movements, poor postures, and sub-optimal equipment design. OBJECTIVE: This study aimed to design, build, and evaluate an endoscope holder for reducing the static load applied by the weight of the endoscope, in order to reduce musculoskeletal disorders risk factors in the surgeon's hand, shoulder and back issues regions. METHODS: A new endoscope holder was designed according to ergonomic design principles. The designed holder was evaluated by surface electromyography (sEMG) and discomfort assessment including 15 laparoscopic surgeons. The results were analyzed with centrality statistics and compared with the independent t-test using SPSS version 22. RESULTS: The evaluation of the new endoscope holder shows a statistical significant decrease in the average electrical activity of biceps brachii, triceps brachii, lateral deltoid, T9 Thoracic erector spinae, L4 Lumbar erector spinae, and external oblique after using the holder (p < 0.05). CONCLUSION: The results shows that using the new endoscope holder is associated with a lower level of discomfort, as well as a lower induced muscle activity. The results also highlight the need to upgrade the holder to offer rotability in all directions (perpendicular to the ground) which will be included in the next design.

Study of The Impact of Users' Features on Dimensional Allowances Resulting from the Use of Personal Protective Equipment.

Up-to-date anthropometric data on the human population are needed for designing safe and ergonomically efficient workplaces. An important determinant of safety and ergonomic comfort at work is knowledge of the value of dimensional allowances (DAs) when using personal protective equipment (PPE) as the dimensions and space occupied by workers increase. This is particularly important in environments characterized by spatial constraints. However, it is not well known to what extent the aforementioned DAs are affected by the users' features. The anthropometric dimensions of 200 people (151 males and 49 females) were obtained from 3D scans, and these became the basis for calculating DAs when using PPE kits normally worn by rescue and technical workers. DAs were determined for the entire body shape of a person wearing three types of PPE kits designed for firefighters, mine rescuers, and welders. In the study, maximum and mean values of height, width, and circumference DAs were obtained. In addition, percentage dimensional increments (DIs) were calculated. A three-dimensional analysis of the human body with and without PPE, involving a 3D scanning methodology, was applied to address the research question. Test results clearly indicate that the values of DAs do not depend on the anthropometric features of users, such as sex, age, and body height percentile-they remain constant for a given type of PPE. The presented data are useful for designing PPE products as well as work tools and infrastructure, including machinery, devices, workstations, means of transport, interiors, and building equipment. The results of the presented study indicate that dimensional allowances play a significant role in interactions between persons wearing PPE and their work environments. The obtained results (DAs and percentage DIs) are included in a new anthropometric atlas of human measures developed by the CIOP-PIB in 2023.

3D Hand Scanning Methodology for Determining Protective Glove Dimensional Allowances.

There are two types of dimensional allowance (inner and external) related to two distinct areas of occupational health and safety: those being a measure of fit of personal protective equipment (PPE) and those determining the safe and comfortable human interaction with tools and machines, e.g., the latter ones result from wearing PPE increasing the dimensions of the human body and generating limitations in the work environment. In this paper, they are taken to mean the difference between the dimensions of a bare and gloved hand (including glove construction and materials). Dimensional allowances are important in designing the work environment, e.g., machine control panels and tools. The absolute and relative maximum values of dimensional allowances determined in this study for a hand in a firefighter's protective glove for the main anthropometric data are: 16.90 mm (5.90%) for length, 12.00 mm (13.77%) for width, and 15.70 mm (7.96%) for circumference. The obtained results are useful for designers, and especially for designing keys on control panels and LCD touch displays and monitors integrated with machines.

Ergonomic Design and Assessment of an Adjustable Laptop Stand Used in the Typing Task.

Background: Laptops are ubiquitous tools in today's society; however, their prolonged use often leads to discomfort and musculoskeletal disorders due to their nonergonomic design. This study aimed to evaluate the effectiveness of an innovative adjustable laptop stand in enhancing comfort and productivity during typing tasks. Methods: A 2-phase experimental design was employed. Phase 1 involved the development of a novel laptop stand considering ergonomic principles and expert recommendations. In Phase 2, a total of 25 office workers-13 men and 12 women-participated in 3 randomized sessions of a 2-hour typing task. They used the newly designed stand, adjusted their laptop height using conventional methods, or completed the task without any height adjustment (control). The Local Subjective Discomfort Questionnaire (LPD), the Rapid Upper Limb Assessment (RULA), and speed and error rates were used to measure postural risk, subjective discomfort, and typing performance, respectively, during each session. SPSS Version 26 (IBM) was used for the analysis, and P ˂ 0.05 was considered statistically significant. Results: The RULA scores were significantly lower with the newly designed stand compared with the other conditions. When using the stand, perceived discomfort in specific regions significantly decreased (P < 0.05). Moreover, the number of typing errors significantly reduced with the stand (P < 0.05), while no significant difference was observed in typing speed (P = 0.371). Conclusion: The novel adjustable laptop stand significantly reduced discomfort and improved typing accuracy during typing tasks, suggesting its potential to enhance user comfort and productivity. However, further longitudinal studies are needed to assess the long-term effects of this intervention.

Analysis of the auricles and auricular shape types for ear-related wearables: A study of mainland Chinese sample aged 15-79.

BACKGROUND: Comprehension of the complex shape of the auricle and how it differs in terms of factors such as sex, age, and side have become an imperative aspect of the fabrication and service delivery of products that are natural, functional, and healthy for users. OBJECTIVE: This study was aimed at providing a clear understanding of the anthropometric characteristics based on age, sex, size, and side and shape type of the auricles of mainland Chinese samples. METHODS: Casting and 3D scanning were employed to obtain eighteen auricular measurement variables from 1120 subjects (aged 15-79). Examination of sex-related and bilateral differences were conducted. Furthermore, factor analysis was employed to establish the factors associated with the variations in auricular shape. Also, hierarchical cluster analysis was performed to classify the auricular shapes of individuals. RESULTS: The auricular inclination angle, conchal depth and tragal height did not exhibit any specific trend across the age groups. No significant bilateral difference was observed in both genders. The auricular shapes were classified into five types according to six major factors. CONCLUSIONS: It was observed that measurement variables of the Chinese auricles changed continuously with age, with most of the linear variables exhibiting a steady increase. The apparent strong association between the auricular types and age groups indicate that a person's auricular shape may change with age.

Child restraint headrest and belt routing design features and their association with child passenger behavior and restraint misuse.

OBJECTIVES: Ergonomic design of child restraint systems (CRS) may facilitate optimal travel behavior and crash protection of child passengers during motor vehicle trips. However there have been few studies examining the relationship between CRS design and child passenger travel behavior. The aim of this study was to examine whether associations between CRS design features and child passenger behavior exist during real-world, everyday vehicle trips. METHODS: Video from a naturalistic driving study (NDS) was analyzed in this study. Families drove an instrumented study vehicle for approximately two weeks with at least one child aged between one and eight years traveling in their own forward-facing (FF) CRS or belt positioning booster (BPB). Video for one child passenger was randomly selected from each trip for analysis. Video was coded for five-second epochs at nine time points (5%, 17%, 25%, 30%, 50%, 53%, 75%, 89% and 95% of trip length). Two types of child passenger travel behaviors were identified by manual review of the video and audio recordings: (i) optimal/suboptimal head position and (ii) correct/incorrect use of the internal harness/shoulder belt. Video screenshots were used to characterize CRS design features. Random effects logistic regression models were used to examine the associations between specific CRS design features and the travel behaviors of interest, whilst accounting for clustering of data by child and trip. RESULTS: Suboptimal head position was associated with the absence of a height adjustable headrest and a narrow headrest wing width in FFCRS. Incorrect harness use in a FFCRS was associated with the absence of an adjustable headrest, in addition to headrest features such as wing width and depth. In BPBs, a reduction in suboptimal head position was associated with the absence of a sash belt guide, however no restraint design features were associated with incorrect shoulder belt use. CONCLUSIONS: Some CRS design features may influence undesirable child passenger travel behavior. These early findings support enhanced and user-centric CRS design as a likely important mechanism to improve child passenger safety.

Ergonomic Rationalization Sequence of Digital Lighting Design in the Working Environment.

This paper describes the creation of a rationalization sequence for working with simulation models, and its subsequent verification in the redesigning of lighting in cooperation with digital enterprise tools. The rationalization sequence consists of 11 sequences, whose accuracy is subsequently verified on a practical example of the redesign of an assembly room of a production hall in the simulation tool Dialux Evo. In conjunction with the proposed procedure, a redesign of the assembly workplace located in the production hall for daylighting, artificial, and mixed lighting was created. The conclusion of the paper provides an overview of the benefits gained from the application of the work environment rationalization procedure.

Tibia Nailing Using Modular Stand: A Technical Note.

Interlocking nailing is a well-established procedure for managing unstable tibial shaft fractures. Closed reduction and internal fixation of the tibial shaft fractures require ease of intraoperative positioning, maneuvering, and biplane imaging. We describe the use of an innovative modular tibia-nailing stand, which greatly enhances the ergonomics of the tibia nailing procedure.

Anthropometric perspective to classroom furniture ergonomics and the need for standards in Nigerian schools.

BACKGROUND: Classroom furniture designs have been implicated in musculoskeletal disorders among school age persons due to high level mismatches between the furniture dimensions and users' anthropometrics. OBJECTIVE: The objective of the study was to analyze classroom furniture ergonomics at selected primary, secondary and tertiary educational institutions in Nigeria and to understand if there are noticeable patterns in the match/mismatch. METHOD: Anthropometric measures relevant to furniture design were obtained from primary and secondary school children as well as from university undergraduates. The dimensions of classroom furniture available to the participants were also taken and an assessment of the suitability of the furniture was completed. RESULT: The ergonomic evaluation of the classroom furniture available to the study participants revealed enormous discrepancies between the furniture dimensions and the anthropometric measures of the users. In addition, a pattern was observed in the way the matches/mismatches occurred. The furniture dimensions that matched majority of the users tend to match across the three categories and those that did not match majority of the students, also followed the same pattern. CONCLUSION: The study presents remarkably high levels of mismatches between classroom furniture and users' anthropometrics and therefore calls for a review of the policies for classroom furniture design in Nigeria, if at all any policy exists.

Procedure for Determining Dimensional Allowances for PPE Using 3D Scanning Methods.

The article describes the importance of dimensional allowances, which are a consequence of the use of personal protective equipment (PPE) for work safety. The method of 3D scanning was proposed for determining the dimensional allowances which has been preliminary validated. Two geometric solids (a cylinder and a cuboid) were used to approximate the minimum space around the person using PPE. The solids are a simplified representation of the silhouette of a human subject performing activities in a confined work environment. They also correspond to the typical shapes of access openings and confined spaces, reflecting the real working conditions of welders, firefighters, mine rescuers, and other rescue teams. A detailed analysis of dimensional allowances for a full welding PPE set is provided. Based on the adopted parameters: the dimensions of the body, the base area and the volume, the differences in the dimensions of the body of a person dressed in underwear and in PPE were compared. The results of the presented studies indicate a significant role of dimensional allowances in interactions between persons wearing PPE and the work environment. The results are planned to be implemented in a new anthropometric atlas of human's measures used for ergonomic design.

Design and ergonomic assessment of a passive head/neck supporting exoskeleton for overhead work use.

Overhead work is an important risk factor associated with musculoskeletal disorders of the neck and shoulder region. This study aimed to propose and evaluate a passive head/neck supporting exoskeleton (HNSE) as a potential ergonomic intervention for overhead work applications. Fourteen male participants were asked to perform a simulated overhead task of fastening/unfastening nut in 4 randomized sessions, characterized by two variables: neck extension angle (40% and 80% of neck maximum range of motion) and exoskeleton condition (wearing and not wearing the HNSE). Using the HNSE, significantly alleviated perceived discomfort in the neck (p-value = 0.009), right shoulder (p-value = 0.05) and left shoulder (p-value = 0.02) and reduced electromyographic activity of the right (p-value = 0.005) and left (p-value = 0.01) sternocleidomastoid muscles. However, utilizing the exoskeleton caused a remarkable increase in right (p-value = 0.04) and left (p-value = 0.05) trapezius electromyographic activities. Performance was not significantly affected by the HNSE. Although the HNSE had promising effects with respect to discomfort and muscular activity in the static overhead task, future work is still needed to investigate its effect on performance and to provide support for the generalizability of study results.