Seating System Research Articles

차량 시트 가진 및 작동 내구 BSR 시험법 연구

자동차에서 발생하는 BSR 소음은 감성품질로써 최근에 크게 대두되고 있다. 본 논문에서는 차량 시트에서 발생하는 BSR 소음에 대하여 두 가지의 시험법을 적용하였다. 첫째, sine sweep 가진 BSR 시험법을 이용하여 저주파 가진으로 인해 발생하는 고주파의 BSR 소음을 정량적으로 분석할 수 있음을 확인하였다. 둘째, 작동 시 주요 부위 가속도를 계측하는 작동 BSR 시험법을 이용하여 시트의 여러 조절 장치 중 하이트 조절 장치의 작동 BSR 소음원을 분석 할 수 있었다. 이때 내구시험을 통해 소음원을 발생시켰으며 그에 상응하는 BSR 소음이 한 사이클 당 총 14회 발생하고 있음을 확인하였다. 본 논문에서 제시된 두 가지의 시험법은 시트의 BSR 소음을 보다 효과적으로 분석할 수 있다. 【BSR noise from automobiles is largely issued in recent as an emotional quality. This study describes the two test methods for determining BSR noise occurred in automotive seat system. First, the sine sweep test is found to be an effective excitation method for determining BSR noise with high frequency. Second, BSR operation test is introduced in such a way that BSR noise during operation of seat height system is measured by several accelerometer at each 800 cycles until 6400 cycles. The periodic noise signal is captured during one cycle after many cycles of operation. Two test method presented in this paper can be analyzed more efficiently BSR noise of the seat.】

Adaptive control of an active seat for occupant vibration reduction

The harmful effects on human performance and health caused by unwanted vibration from vehicle seats are of increasing concern. This paper presents an active seat system to reduce the vibration level transmitted to the seat pan and the occupants’ body under low frequency periodic excitation. Firstly, the detail of the mechanical structure is given and the active seat dynamics without external load are characterized by vibration transmissibility and frequency responses under different excitation forces. Owing the nonlinear and time-varying behaviour of the proposed system, a Filtered-x least-mean-square (FXLMS) adaptive control algorithm with on-line Fast-block LMS (FBLMS) identification process is employed to manage the system operation for high vibration cancellation performance. The effectiveness of the active seat system is assessed through real-time experimental tests using different excitation profiles. The system identification results show that an accurate estimation of the secondary path is achieved by using the FBLMS on-line technique. Substantial reduction is found for cancelling periodic vibration containing single and multiple frequencies. Additionally, the robustness and stability of the control system are validated through transient switching frequency tests.

Adaptive seating systems in children with severe cerebral palsy across International Classification of Functioning, Disability and Health for Children and Youth version domains: a systematic review.

The aim of this study was to systematically review the effect of adaptive seating systems (AdSSs) in young people less than 19years of age with severe cerebral palsy (CP), with particular focus on child-related outcomes across all components of the functioning and disability domains of the International Classification of Functioning, Disability, and Health for Children and Youth version (ICF-CY). Literature searches of studies published from 1975 to October 2014 were performed. Methodological quality and the risk of bias were analysed using Sackett's level of evidence, the American Academy for Cerebral Palsy and Developmental Medicine guidelines, and Mallen criteria for observational studies. Nine studies fulfilled the selection criteria. All studies had level IV evidence and were of moderate methodological quality. The results focused on the effects of AdSSs on postural control and on upper extremity function and on additional child-related outcomes. The results suggested that AdSSs that include trunk and hip support devices may improve postural control outcomes, and that special-purpose AdSSs may improve self-care and play behaviour at home. Because of a low level of evidence and the moderate methodological quality of the studies available, no robust conclusions can be drawn. Nevertheless, the data suggest that AdSSs may be able to improve activity and participation at home among children with severe CP. More studies of high methodological quality addressing the effect of AdSSs on activity and participation are urgently needed. Suggestions for future research are provided.

A new landing impact attenuation seat in manned spacecraft biologically-inspired by felids

When manned spacecraft comes back to the earth, it relies on the impact attenuation seat to protect astronauts from injuries during landing phase. Hence, the seat needs to transfer impact load, as small as possible, to the crew. However, there is little room left for traditional seat to improve further. Herein, a new seat system biologically-inspired by felids’ landing is proposed. Firstly, a series of experiments was carried out on cats and tigers, in which they were trained to jump down voluntarily from different heights. Based on the ground reaction forces combined with kinematics, the experiment indicated that felids’ landing after self-initial jump was a multi-step impact attenuation process and the new seat was inspired by this. Then the construction and work process of new seat were redesigned to realize the multi-step impact attenuation. The dynamic response of traditional and new seat is analyzed under the identical conditions and the results show that the new concept seat can significantly weaken the occupant overload in two directions compared with that of traditional seat. As a consequence, the risk of injury evaluated for spinal and head is also lowered, meaning a higher level of protection which is especially beneficial to the debilitated astronaut.

Two Seating Systems' Effects on an Adolescent With Cerebral Palsy and Severe Scoliosis.

To compare physiological functioning, communication switch activation, and response accuracy in a 19-year-old young man with quadriplegic cerebral palsy and neurological scoliosis using 2 seating systems within the school setting. Prospective single-subject alternating treatment design with 2 conditions: baseline phase with standard planar inserts (A1), custom-molded back with original seat (B), and return to baseline (A2). Measures included oxygen saturation (SaO2), heart rate (HR), respiration rate (RR), body temperature (BT), processing time to activate switches, and response accuracy. SaO2 levels increased from "distressed" to "normal"; variability decreased. HR, RR, and BT fluctuations decreased with the custom-molded back. Processing time decreased with increased variability, affected by subject's motivation; accuracy improved slightly. Reported social approachability and student-initiated communication increased. SaO2 increased and HR, RR, and BT fluctuations decreased with a custom-molded back. Graphing data may help determine seating effect with complex clients.

Timeaxis Design of Health Monitoring Seat System Using M Method and SysML

This paper describes the design of Health Monitoring Seat System, a safety device that prevents health related traffic accidents. The current system can only prevent drowsy driving, and cannot consider individual differences. Therefore, the purpose of this study is to design a new system that optimizes to an individual, and provides functions that work towards the driver's health condition. To realize this system, the Timeaxis Design, a concept incorporating the viewpoint of time into the theory and methodology of design, is introduced. The perspective of Timeaxis Design, enables the design of a system undergoing several development stages necessary for realizing this system. The system undergoes three development stages: STAGE I (existing technologies), STAGE II (developing technologies), and STAGE III (conceptual technologies). In order to design the system, the driver's physical and psychological health conditions must be put into concern. Therefore, the M Method and SysML is used in the designing process. The M Method is a design method that can describe the relationship of the physical and psychological element of a human. The SysML is a graphical modeling language that visualizes the development process of a system. As a result, three subsystems: “Data analysis system”, “Monitoring system”, and “Seat system” that construct this system are proposed. Furthermore, by considering the Timeaxis Design, the road map for the technological development of this system is derived.

Pediatric seating system

Pediatric seating system

1205 体調モニタシートシステムラインアップのタイムアクシスデザイン(OS13-2 タイムアクシスデザイン,OS13 タイムアクシスデザイン)

1205 体調モニタシートシステムラインアップのタイムアクシスデザイン(OS13-2 タイムアクシスデザイン,OS13 タイムアクシスデザイン)

2314 M Methodを用いた体調モニタシートシステムのデザイン(OS14 デザイン科学)

2314 M Methodを用いた体調モニタシートシステムのデザイン(OS14 デザイン科学)

Preface

Preface

A comparison of flat and ramped, contoured cushions as adaptive seating interventions for children with neurological disorders

This study is a part of an ongoing effort to address the lack of rigorous, scientific evidence to inform the prescription of adaptive seating interventions for children with neurological disorders. The aim is to investigate one aspect of the seat – the cushion, at the same time as developing a battery of tests which are objective, easy to implement and reliable with which adaptive seating interventions can be measured. Method: A total of 35 school-aged children with neurological disorders were assessed in a bespoke adaptive seating system to compare the use of a flat and a ramped, contoured cushion. The measures used were an accelerometer to measure stability, two actigraphs to measure activity, a pressure mapping system to measure weight distribution, goniometry to measure posture and activities to measure functional ability. Results: The results generally support the use of ramped, contoured cushions over flat cushions. The accelerometer and pressure mapping system show particular promise in future research. The actigraphs were unreliable, although other models may prove more suitable. The goniometry produced the best results, although it was the least reliable to implement and the seated functional activities need further work. Interpretation: The methodology showed in a number of ways that ramped contoured cushions were more effective than flat seat cushions for a heterogeneous population of children. Accelerometry and pressure mapping showed particular promise for advancing research and practice in the area of adaptive seating, with further work required in other areas. In particular, it is recommended that future efforts pursue the use of more reliable electronic measurement.

The influence of active seating on car passengers' perceived comfort and activity levels

New technologies have led to an increasingly sedentary lifestyle. Sedentary behaviour is characterised by physical inactivity and is associated with several health risks. This excessive sitting does not only take place in the office or at home, but also during daily commute. Therefore, BMW AG developed an active seating system for the back seat of a car, consisting of sensors in the back rest that register upper body movements of the passenger, with which the passenger controls a game. This study evaluated three different aspects of active seating compared to other tasks (reading, working on laptop, and gaming on tablet). First, discomfort and comfort perception were measured in a 30-minute driving test. Discomfort was very low for all activities and participants felt significantly more challenged, more fit and more refreshed during active seating. Second, heart rate was measured, indicating a light intensity, but nevertheless non-sedentary, activity. Third, average and variability in activity of six postural muscles was measured by electromyography (EMG), showing a higher muscle activity and higher muscle variability for active seating compared to other activities. Active seating might stimulate movements, thereby increasing comfort and well-being.

The Design of Driver’s Seat Vibration System of the Road Roller Based on MATLAB

This project mainly studies the structure composition and the working principle of the seat vibration system of the roller . On this basis, dynamic equations are obtained according to the stress analysis of the simplified system of the seat vibration system of the roller, and then with the simulink module of MATLAB software, a simulation model is established as to the driver's seat system.Through the model simulation, the roller’s vibration of the the driver seat system is analysed,then based on the analysis, the optimization design can be done. Finally, through the research of this topic, the ride comfort of roller is been improved.

Development of a modularized seating system to actively manage interface pressure.

Pressure ulcers can be a fatal complication. Many immobile wheelchair users face this threat. Current passive and active cushions do reduce the incidence of pressure ulcers and they have different merits. We proposed an active approach to combine their advantages which is based on the concept that the interface pressure can be changed with different supporting shapes. The purpose of this paper is to verify the proposed approach. With practical applications in mind, we have developed a modular system whose support surface is composed by height-adjustable support elements. Each four-element module was self-contained and composed of force sensors, position sensors, linear actuators, signal conditioners, driving circuits, and signal processors. The modules could be chained and assembled together easily to form different-sized support surfaces. Each support element took up a 3 cm × 3 cm supporting area. The displacement resolution was less than 0.1 mm and the force sensor error was less than 1% in the 2000 g range. Each support element of the system could provide 49 N pushing force (408 mmHg over the 3 cm × 3 cm area) at a speed of 2.36 mm/s. Several verification tests were performed to assess the whole system's feasibility. Further improvements and clinical applications were discussed. In conclusion, this modularized system is capable of actively managing interface pressure in real time.

A design for the priority seating system on Taiwan buses

A design for the priority seating system on Taiwan buses

Assessment of the Accuracy of Certain Reduced Order Models used in the Prediction of Occupant Injury during Under-Body Blast Events

It is of considerable interest to developers of military vehicles, in early phases of the concept design process as well as in Analysis of Alternatives (AoA) phase, to quickly predict occupant injury risk due to under-body blast loading. The most common occupant injuries in these extremely short duration events arise out of the very high vertical acceleration of vehicle due to its close proximity to hot high pressure gases from the blast. In a prior study [16], an extensive parametric study was conducted in a systematic manner so as to create look-up tables or automated software tools that decisionmakers can use to quickly estimate the different injury responses for both stroking and non-stroking seat systems in terms of a suitable blast load parameter. The primary objective of this paper is to quantitatively evaluate the accuracy of using such a tool in lieu of building a detailed model for simulation and occupant injury assessment. Language: en

스마트워크센터 환경에서 협업을 위한 좌석 추천 시스템 개발

VMS SolutionsWith the development of Information Communication Technology and a way of solving problems such as productivity improvement, advanced working attitude, greenhouse gas reduction, low birth rate, aged problem, etc., the need of smart work is increasing. Getting out of legacy working types that are limited in time and space, the flexible seat system at a smart work center that supports the smart working environment is proposed. However, the seat choice based on employee’s emotional judgement may cause the decline of forming cooperative space and mutual communication because of the scattered seat arrangement between employees. This paper proposed a seat recommendation method for the mutual cooperation at a smart work center. The method is based on a work similarity of employees. A prototype system also implemented to show the feasibility.

Pilot study of strap-based custom wheelchair seating system in persons with spinal cord injury.

Custom wheelchair seats can be used to help prevent pressure ulcers in individuals with spinal cord injury. In this study, a strap-based system was evaluated in three Veterans with spinal cord injury. Interface pressure distributions were measured after transfers, wheeling, and pressure relief maneuvers and after fittings by three different therapists. We found that pressure distribution measures were not generally affected after transfers and wheeling using the strap-based wheelchair and that pressure relief maneuvers were able to be performed. Additionally, all therapists were able to customize the wheelchair seat to clinically acceptable levels in 4 to 40 min for the three subjects. Future studies can test the long-term effects of using the strap-based wheelchair seat and identifying individuals that would most benefit from a rapidly customizable wheelchair seat.

Analysis and Optimization of Cushion Seat Supporting Members

Seat structures play a major role in the car passive safety. Due to their adjustment function mechanisms are generally involved in the seat failure mode. With the current evolution of automotive techniques, one of major automotive industry priorities is to decrease the product mass, design quicker and more efficient vehicles, emphasizing on travelling greater distances in short interval of time. For this comfort with safety of passengers is very important, thus the design of the seating system is very important. At the same time, seat rails have to fulfill high quality criteria, there are very strict requirements regarding strength and crash worthiness as the seat rail is regarded as a safety component it transfers forces from the driver / passenger to the car floor structure in case of a crash and they have to provide individual length adjustments possible. Amongst many parts, the seat tracks (upper and lower tracks) carry most of the load on seat structure considering human load. The aim of this project is to optimize an automotive seat track by reducing track thickness and its cost subjecting to static analysis. The adopted design has thickness of seat track as 1.5mm; scope of the present work involves Finite Element Modeling of Seat track assembly using HYPERMESH R 10. Pre-processing steps such as updating of element type, material properties, application of loads and Boundary condition is performed using HYPERMESH. The element type considered for the analysis is SHELL. Processing is carried using ANSYS. The results in the form of stress and displacement are extracted using HYPER VIEW.

The Study on Sitting Pressure of Modular Seating System about Seat Wedge Height Applied to Cerebral Palsy

The Study on Sitting Pressure of Modular Seating System about Seat Wedge Height Applied to Cerebral Palsy