Chair Design Research Articles

APPLICATION of MANUFACTURING SYSTEMS TO CALCULATE PRODUCTION TARGET NEEDS PRIDE CHAIR DESIGN

A process in a company or industry will never be separated from the name of the production, production is an important part of the running
 of a company or industry. This research aims to provide input to the company to be able to
 calculate the need for future production targets based on previous production data so that the company can prepare all production needs.
 Production can also be interpreted as an activity to increase the use of goods and
 benefits in fulfilling daily activities. In practice, a person or business entity that
 carries out production activities is called a producer. Producers produce goods to be sold to meet the needs of others and
 theirindividuals. Production activities, there is an activity of processing raw materials into
 semi-finished materials, and then proceeding from semi-finished materials to finished materials. Therefore, a separate focus is
 needed to determine the amount of production, output, and input that is done. One thing that
 can be done is knowing up to calculating the needs of all processes to the production target. While the focus of production activities from
 the production system to inventory is First, forecasting is important and foremost. Second,
 inventory control is very important in the production system for inventory, especially in planning the purchase and delivery of raw
 materials and components. Third, the production of large quantities of inventory
 items is more structured.

Automatic Sitting Pose Generation for Ergonomic Ratings of Chairs.

Human poses play a critical role in human-centric product design. Despite considerable researches on pose synthesis and pose-driven product design, most of them adopt the simple stick figure model that captures only skeletons rather than real body geometries and do not link human poses to the environment (e.g., chairs for sitting). This paper focuses on user-tailored ergonomic design and rating of chairs using scanned human geometries. Fully utilizing the anthropometric information of the human models, our method considers more ergonomic guidelines of chair design (such as pressure distribution and support intensity) and links the geometry of 3D chair models and human-to-chair interactions into the pose deformation constraints of the human avatars. The core of our method is a pose generation algorithm which rigs the user's successive poses through coarse- and fine-level pose deformations. We define a non-linear energy function with contact, collision, and joint limit terms, and solve it using a hill-climbing algorithm. The fitting results allow us to quantitatively evaluate the chair model in terms of various ergonomic criteria. Our method is flexible and effective and can be applied to users with varying body shapes and a wide range of chairs. Moreover, the proposed technique can be easily extended to other furniture, such as desk, bed, and cabinet. Extensive evaluations and a user study demonstrate the efficiency and advantages of the proposed virtual fitting method. Given that our method avoids tedious on-site trying, facilitates the exploration/evaluation of various chair products, and provides valuable feedback for the designers and manufacturers to deliver customized products, it is ideal for online shopping of chairs.

Application of homogenization approaches to the numerical analysis of seating made of multi-wall corrugated cardboard

Corrugated cardboard presents small geometries that make unfeasible the use of detailed three-dimensional numerical models, though homogenization approaches can be used to define equivalent homogenous plate models at a macro-mechanical scale. In this paper, we performed a finite element analysis of a well-known chair design, originally made of honeycomb cardboard, but replacing this material with single- and multiple-wall corrugated cardboard. We compared the deflections obtained under some load cases defined by he European Standards EN1728 and EN12520 for seating designs, with those obtained for another commercial chair design, originally made of heavy-duty triple-wall corrugated cardboard, finding comparable values. We also analysed optimized versions of both chairs, achieving lower deformations. In this way, we could find for each case the material settings with the better resistance-to-cost ratio, thus proving the utility of homogenization techniques on corrugated cardboard furniture design, as an aid to choose the most appropriate material settings.

Design, Analysis, and Implementation of a Four-DoF Chair Motion Mechanism

In this study, the proposed design of a motion chair with four degrees of freedom (DoF) provides the pilot with the tactile sensations required by the human body to increase the immersion of flight simulation training. The chair includes a seat pan, a back pad, and a seat height. For the development of the proposed mechanism structure, the modular design is used to achieve the required displacement and acceleration. In addition, inverse kinematics is also constructed to meet the actuation needs. The control system can achieve real-time closed-loop control using an industrial computer, a motion control card, servo motors and drivers. This enables the structure to reach destinations with the shortest motion time and completes the required T-curve motion trajectory. The displacement, velocity, and acceleration of the designed structure are analyzed using SimWise4D software to verify the performance specifications of the structure. The experimental results indicate that the four-DoF control meets requirements of displacement, velocity, and acceleration.

A Framework of Design Concept Generation Framework with Operations on Extensional Concept Space

A concept space is a graphical tool to map keywords and images of design visually onto a metric space. While it stimulates designers’ability of problem finding and ideation, there are open issues toward design concept generation. This paper proposes a framework of design concept generation with an extensional concept space (ECS). ECS is a metric space of the characteristics, i.e., function and physical attribute, each of which is a set of entities that fall under its definition. The concept distant measurement method based on word2vec with Wikipedia corpus is adopted to extract concepts from documents of design cases and to build a concept space. The framework facilitates a designer to explore a concept space that contains the text and image information with iterative operations, such as function development, and create a new design. This paper demonstrates a case study of chair design to verify the effectiveness of the proposed framework.

A.I 시대의 새로운 디자인 도구 사례 연구: 의자 디자인을 중심으로

A.I 시대의 새로운 디자인 도구 사례 연구: 의자 디자인을 중심으로

Designing a Tourism Minibus Driver Chair by Using IDEAS Framework in a Virtual Environment

Indonesia is a high tourism sector country which provides opportunities for tour and travel service business. Thereby increasing the growth rate of accidents by 3.3%, one of which was caused by buses. Hafizh 58 Jaya, a company in the field of tourism services, had many complaints against drivers about the problem of muscle disorders due to the lack of ergonomic position of the driver or the seat used which was not suitable with the user or not ergonomic. To analyse this problem, IDEAS framework was applied. This method could describe overall minibus driver movement and produce designs that were appropriate with the level of risk on small musculoskeletal disorders. By normal driving activity, the second driver had the largest PEI parameter index value, 2,186. It was categorized as medium to low-risk musculoskeletal disorders. This meant that the actual chair with normal driving activity was not optimal and not ergonomic. The final design of the redesign chair has given optimal and ergonomic results shown by highest PEI index parameter value of 1,336. This PEI index parameter was categorized at the low risk of musculoskeletal disorders.

DESIGN OF ERGONOMIC CHAIR FOR GRINDING OPERATION

One of essential production activities is grinding process. This process mainly involves the constant activity of eroding a surface to be smoother or more evenly, cutting a workpiece, creating profiles like angles and arches, sharpening a cutting tool, and finishing a final product. Meanwhile, there is no study evaluating the risk levels of workers working on grinding, and there is no unique chair specifically designed for the process. Therefore, this study aims to assess the risk levels of a grinding worker and to propose the design of an ergonomic chair that is adjustable, comfortable, durable, and keen to be used. The risk levels of the grinding workers were evaluated using REBA, while the ergonomic chair design was based on anthropometric data taken from 4 grinding workers in Bantul, Special Region of Yogyakarta, Indonesia. The researchers selected a buttock-popliteal length (seat depth), lower leg length (popliteal height) and hip breadth sitting as anthropometric measures to make a chair design for the grinding operations. After that, the existing adjustable chair designs were also considered and evaluated to get better adjustable-ergonomic chair design for the grinding operations. The results show that it is important that the stakeholders improve most of the grinding operations of the workers, especially by using an ergonomic chair design for grinding operation that is adjustable, comfortable, durable, and reliable. The chair height can be adjusted from 361-414 mm to adapt with the users, and the variation in product height aims to prevent bending on the back. Finally, the grinding chair can reduce the risk level from the high and medium level to the low-risk levels of working postures.

A Combination Design of Bag, Chair, Charger, Tables Made with Hazardous Waste Raw Materials in Tackling Environmental Pollution in the 4.0 Revolution Era

The design of bags, chairs, chargers and tables is intended for commuter workers who carry out mobility activities every day. Design works that help to support commuter worker activities use a multi-functional system. The multi-function system is indicate by the shape and features attached. This product design method uses several stages including; 1) problem identification; 2) literature study: 3) design sketches, and: 4) design. The design results are turned into chairs, tables for lesehan (sitting on the floor) and bags. In addition, the other things are the storage box to store equipments for commuter workers while doing mobility and a solar cell which functions to capture sunlight which will be converted into electrical energy for energy sources to charge cellphones. Design works can be used in accordance with their respective functions. Design works carry the principle of multifunction, easy use, strong, lightweight and flexible. It is hoped that the design for this multi-functional products can be practical in use in the development of creative industries, and can overcome environmental pollution problems. From a theoretical perspective, it can be a reference for academics and science.

The ergonomic factor application for improvement of performance office staff

Comfortable workplace, healthy and safely is the goal of implementing occupational safety and health requirements. Ergonomics is one of the factors that can affect employee productivity. Achieving harmony between labor, equipment, environment, work methods and work processes is the most important application of ergonomics. The purpose of this study is to investigate the improvement of working conditions through the application of ergonomics in the workplace. Ergonomic testing is carried out using the Rapid Upper Limb Assessment (RULA) analysis method to evaluate worker posture on work machines or operating systems and to investigate reduction in upper extremities and Ergonomic Factor Policy Identification (SHORT), which is an ergonomic evaluation method that focuses on frequency, duration, weight and posture to identify ergonomic hazards faced by everyday workers using an assessment system. The results of ergonomic application analysis are on average at a low risk level. Improvements can be made to reduce the level of risk experienced by employees in accordance with ergonomic standards, including improving the design of tables and chairs, adjusting work positions, avoiding odd work positions, stretching muscles while doing work at the computer.

Aestheticity and Durability Optimization in Industrial Chair Design

Sandalye, yaygın olarak kullanılan ve piyasada çeşit ve türü çok fazla olan bir mobilyadır. Mobilya piyasasındaki çoğu firma, sandalyeyi fabrikasyon olarak üretmektedir. Bu seri ve yığın halinde üretilen sandalyelerin büyük çoğunluğu mühendislik hesaplarına ve estetik gerekliliklere dayalı değildir. Bu nedenle çalışmanın amacı endüstriyel sandalye tasarımında estetiklik ve dayanıklılık optimizasyonu üzerinedir. Çalışmada yöntem olarak dayanıklılık analizine dayalı olarak eleman boyutları ve birleşme yerleri belirlenmiş ve bu analizin izin verdiği kısımlarda estetiklik optimizasyonu yapılmış 9 adet tasarım (çam, meşe ve Doğu kayını) sandalye örnekleri üretilmiştir. Aynı zamanda mobilya pazarlama piyasasından rastgele yöntemle belirlenmiş firmalardan 9 adet endüstriyel (çam, meşe ve Doğu kayını) sandalye temin edilmiştir. Bu sandalyelere TS EN 1728 ve TS EN 1729-2’ye uygun sağlamlık testi uygulanmıştır. Bu testlerin sonucunda, bu iki grup sandalyelere uygulanan testler ile belirlenen sandalye dayanıklılık değerleri birbirleri ile karşılaştırılmıştır. Karşılaştırma sonucu piyasadan alınan sandalyelerin sağlamlığı tasarım sandalyelerin sağlamlığından daha az olduğu belirlenmiştir. Ayrıca, endüstriyel sandalyelerde ergonomik form ve ölçülere önem verilmediği görülmüştür. Tasarım sandalyelerde bu sorunlar düzeltilerek, endüstri kurumlarına öneri olarak sunulmuştur.

School chair design and key criteria from the users’ point of view

People are becoming increasingly sedentary, including students attending the upper level of primary education. Due to school, young people spend a lot of time sitting in class and at home, which has a negative effect on their health, especially if their work environment, including school furniture, does not meet all the criteria in terms of physiological, psychological, and sociological guidelines for healthy furniture design. Chairs, as school furniture, have been designed according to standards that take into account ergonomic compliance with the body height of pupils. Slovenian classrooms are equipped with standard conventional chairs. In our student-oriented research, we were interested in whether chairs designed according to the standard are suitable for adolescents and what, if any, additional criteria must be met from the users’ point of view. The study included 192 upper level pupils (56.3 % girls and 43.7 % boys), age of 12.4 ± 1.7 years. The research is based on quantitative and qualitative methodology. The descriptive causal non-experimental method was supported by the observation method. The results of the survey show that older students (81.6 %) are of the opinion that they spend more time at school than at home. Due to prolonged sitting, older students (55.3 %) report problems more often than younger ones (28.4 %). Nearly two-thirds of younger students (63.8 %) also believe they sit more in school than at home. The results show that prolonged sitting negatively affects their health or general well-being. Differences between the responses of older and younger pupils are statistically significant both in the opinion expressed regarding the location of sitting (p = 0.010) and in the reporting of problems due to prolonged sitting (p = 0.001). There are no statistically significant differences between the sexes in both groups of older and younger pupils. Pupils sit on hard, uncomfortable, conventional chairs that are not tailored to their needs. They want to use comfortable, soft, swivel chairs with backrests and armrests. The study has shown that, in addition to comfort, school chairs must provide dynamic or active sitting. The present study confirms that static and rigidly shaped school chairs do not offer support for active and restless youth. Therefore, chair design must change to meet the physical, ergonomic, cognitive, and social needs of their users.

Finite element study of sitting configurations to reduce sacroiliac joint loads

Low back pain can be caused by prolonged sitting, originating in the sacroiliac joint (SIJ) in up to 30% of patients. The goal of this study was to develop a finite element model of the lower back and pelvis to study sitting configurations that could minimize the loads in the SIJ while sitting. The configurations were based on chair designs with geometries known to show some benefits according to literature: a 5° downward seat pan tilt and a 20° backrest recline. Both chairs were evaluated in neutral spine position with upright posture and 30° forward leaning configurations. A finite element model of the lumbar spine, pelvis and femurs was developed to compute the reaction forces at the SIJ. The intricate spinal geometry was simplified, and isotropic material properties were assumed for all components. The chair reaction forces were first computed analytically, then inputted as loads on the model. The results demonstrate that the improved sitting configuration reduced the loads in the SIJ compared to a conventional chair in both upright and forward leaning positions by 5.57 % body weight (BW) and 14.18 %BW, respectively. The proposed sitting configuration with a downward inclined seat pan and forward leaning back was shown to be an effective method to reduce SIJ loads.

Enhancement of ergonomic wearable chair with voice controlled using Raspberry pi

Ergonomics is the designing of products and systems that suit a range of people who use them. The Ergonomically designed wearable chair ensures the ability of the user to sit and stand anywhere. It provides the convenience and required posture for their workplace thereby overcoming disabilities caused due to long hours of standing and sitting. This device increases the efficiency of the user by reducing tiredness, pain in the lower back, leg and ankle region. Enhancing the wearable device with voice control will facile the operation of the system and provide automatic control over the device. The chair is wearable due to its exoskeleton-like design and portable due to its lightweight arrangement. This paper elaborately explains the design, mechanism, and application of the wearable ergonomic chair with voice automation. Future developments and challenges are also discussed in this paper.

REDESIGN OF BREASTFEEDING CHAIR FOR NURSERY ROOM

Breastfeeding chair is one of the essential facilities in the airport. This study designs the breastfeeding chair for the nursery room in Minangkabau International Airport. Quality Function Deployment (QFD) was used to investigate the customer requirements by distributing questionnaires to 100 mothers in Padang West Sumatra. Anthropometry data was also measured form those respondents. The study resulted in a design of ergonomic breastfeeding chair which was used features obtained from the voice of the customers. The design has considered the condition of the mother giving birth by normal as well as a cesarean. The design has an adjustable back seat with an angle of 95o,105o, and 110o; it has an adjustable footrest with 120o, 140o, and 180o angles. The chair has a headrest, baby support pad, a portable baby cushion, an adjustable baby bearings. The chair has also equipped with an assemble torn neck, a small drawer on the side of the chair, and a palm rest that can be used or not by adjusting the height.

A novel bamboo sheet chair and its influence on sitting comfort.

BackgroundIn today’s economy, workers spend increasingly more time in seated positions, leading to a growing scientific interest in chair design. In this study we used body pressure distribution tests to compare a novel bamboo chair with unique structural features to other commonly-used chairs. We studied the bamboo sheet chair’s physical characteristics and comfort to provide a scientific theoretical basis for common use seat design.MethodsA total of 25 (14 male and 11 female) subjects participated in the study. Subjects were divided into six groups according to their body characteristics parameters included stature, weight, shoulder breadth, hip breadth, waist width, popliteal height, buttocks-popliteal length, and buttock-abdomen depth, with three groups for males and three groups for females. Each subject was required to complete specified body pressure tests for three different experimental chairs for three minutes and subjective comfort evaluations were also administered. The pressure indexes were measured from the seat pan and backrest and calculated with MATLAB 2015b, which mainly included maximum pressure (Pm), average pressure (Pa), pressure exponent (Pe) and contact area index (PAI). Three pressure threshold limits of 0.67 kPa, 4.00 kPa and 9.33 kPa and four contact surface indexes were used in the experiment to reflect the contact area between human and chair.ResultsThe contact areas in the backrest (52.96 ± 32.94 cm2) and seat pan (307.75 ± 90.31 cm2) in the middle-to-high threshold pressure range, and the contact areas of the backrest (4.34 ± 5.95 cm2) in the high threshold pressure range of bamboo sheet chair were smaller than the corresponding indexes of the common office chair (81.430 ± 45.04 cm2, p = 0.00; 394.39 ± 98.99 cm2, p = 0.02; 13.54 ± 12.00 cm2, p = 0.00, respectively). The pressure index (2.68 ± 0.88 kPa), maximum pressure (6.66 ± 2.05 kPa), and average pressure (2.42 ± 0.59 kPa) values of the bamboo sheet chair backrest were also found to be lower than those of the office chair (4.32 ± 1.62 kPa, p = 0.00; 10.50 ± 3.88 kPa, p = 0.00; 3.43 ± 0.97 kPa, p = 0.00, respectively). The average pressure on the seat pan was greater than 4 kPa for all subjects, while the average pressure on the seat pan was greater than 9.33 kPa for male subjects with a body mass index (BMI) of 27.48.DiscussionThe bamboo sheet chair’s contact areas within the middle-to-high and high-pressure threshold ranges of the backrest and seat pan were smaller than those of the office chair, indicating that the bamboo sheet chair is effective at relieving pressure. Human body characteristics must be considered in the design of seat functional size. Buttocks-popliteal length, weight, body mass index, body shape and weight distribution, all have important effects on the distribution of body pressure at the human-chair interface.

Ergonomic risk analysis of lecture chairs at the engineering faculty, Hasanuddin University

Uncomfortable college chairs will cause health problems such as low back pain, etc. In addition to health problems will also affect student productivity and enthusiasm for learning. This study will identify the risk of ergonomics from lecture chairs at the Faculty of Engineering UNHAS and also identify and provide recommendations for examples of lecture chairs that should be used. This research will use several ergonomics methods such as REBA and nordic body map. Nordic body maps are used to identify parts of the body that feel pain when sitting in a college chair, while the REBA method is used to identify ergonomic risks when sitting in a college chair. The results of identification using the Nordic Body Map method found that several parts of the student’s body were aching like the neck, back, waist, buttocks. The next research method is the Rapid Upper Limb Assessment, the identification results obtained all students get a RULA 7 value which indicates changes in body posture or work facilities as soon as possible. The end of this study is the design of ergonomic lecture chairs in accordance with the wishes of students

An ergonomic comparison of three different patient transport chairs in a simulated hospital environment

The purpose of this study was to compare caregiver muscle activation and joint angles between two ergonomic transport chairs designed to mitigate discomfort and safety risks associated with patient transport, the Stryker® Prime TC and the Staxi® Medical Chair, and a depot wheelchair. Twenty-three caregivers completed level walking and ramped tasks with each device and an 84 kg manikin. Surface electromyography for the upper extremities and back muscles and motion data were collected. The Staxi showed a statistical trend for higher wrist extensor and flexor carpi ulnaris activity compared to the Stryker chair (p ≤ 0.078) and greater wrist flexion than the Stryker and depot chairs (p ≤ 0.004). The depot chair showed greater peak trunk flexion than the Stryker chair (p = 0.004). Overall results suggest that ergonomic chair design may improve joint positioning of the trunk and elbows when operating patient transport chairs over level and ramped surfaces.

Design and evaluation of an ergonomic chair for near-ground welding based on muscle activity and usability.

Work-related musculoskeletal disorders (WMSDs) are one of the major problems in industrial societies. Awkward postures in theworkplace are considered as a main reasons for these disorders. Therefore, the study and investigation of postures to improve them (in the workplace) have a significant role in appropriate intervention. This study aimed to design an ergonomic chair for near-ground welding operations and evaluate its impact on the electromyography (EMG) activity of a select group of lower limb muscles. The EMG activity of lower limb muscles was measured in eight postures consisting of three postures identified via observing welders at work, and five on-chair postures suggested for chair use during welding. The usability of the designed chair was evaluated through the use of the System Usability Scale (SUS). The results showed that the suggested on-chair postures had significantly lower mean muscle activity compared with the identified postures (p < 0.001). Among the identified postures, kneeling posture had the lowest mean muscle activity (p < 0.01), still significantly higher than the mean activity of the on-chair postures (p < 0.001). Applying a 15° slope to the seat pad led to a decrease in muscle activity and an increase in usability score. The usability score of the chair was acceptable in all postures except KCC-90 posture. Using a suitable chair or support for different work postures can prevent detrimental muscle activities during work and the development of musculoskeletal disorders caused by intense muscle activity due to awkward postures.

Design and Implementation of Sign Language Interpretation System and Wireless Enabled Wheel Chair

Design and Implementation of Sign Language Interpretation System and Wireless Enabled Wheel Chair