The Application of Surface Electromyography in the Assessment of Ergonomic Risk Factors Associated with Manual Lifting Tasks

Summary: The purpose of this study was to evaluate the ergonomic risk factors associated with manual lifting tasks using surface electromyography (EMG). 13 volunteers lifted loads of 6 and 13 kg at two speeds and at two horizontal distances in 3 different postures and three boxes of different sizes, from floor to knuckle height, performing 72 lifting tasks. For each lift, the surface electromyography signals from the erector spinae muscles, bilaterally at T_~10 and L_3, was recorded. The ergonomic risk factors associated with manual lifting tasks were evaluated by comparing the average amplitude of EMG signals from the erector spinae muscles. The EMG average amplitude for lifting the load of 13 kg was 14.3 % greater than that for lifting the load of 6 kg (t=-10.93, P<0.01). The EMG average amplitude at the site of L_3 was 10.3 % greater than that at the site of T_~10 (t=-7.98, P<0.01). The EMG average amplitude when performing “fast” lift was 5.9 %greater than the “slow” lift (t=-4.63, P<0.01). The posture of lifting affected the EMG average amplitude. It was lowest with semi-squat posture and greatest with squat posture (F=27.76, P<0.01). The result of multiple stepwise regression analysis showed that the loads of lifting, the size of box, horizontal distance, posture of lifting, the site of the spine subjected to force, lifting speed were the factors affecting the EMG average amplitude. The most significant factor was the loads of lifting, followed by the site of the spine subjected to force and the lifting speed in terms of risk. The ergonomic risk factors associated with manual lifting tasks includes the loads, posture, lifting speed, horizontal distance, the site of the spine subjected to force etc. The results of signal amplitude of EMG from the erector spinae muscles showed that semi-squat posture is the best posture for lifting tasks.

Household Drill Innovative Design under the Guidance of Ergonomics

The household drill is named 90 Degree, designed by Industrial Design Pilot Program Center(Hereinafter referred to as IDPPC) of Luxun Academy of Fine Arts(Hereinafter referred to as LAFA), which is the only national pilot program center in Chinese industrial design field. 90 Degree is designed for home environment, it helps inexperience users, such as women and the elderly, complete the operation easily, and it makes sure that safe operation and assistance users solve the precise punching, location, storage trash and other operations. According to research among users who can understand or manipulate a drill, the designers find problems of users from the user central perspective, and then they integrate product innovative design methods to propose solutions. When the designers intend to design 90 Degree, they attempt using the user behavior record and analysis system, and start ergonomics study in subjects by double hands operation analysis, using gesture analysis, details of work analysis, time and motion study, etc; meanwhile taking advantages of user experience analysis, behavior intention analysis to do user subjective perceptual evaluation. The functions, structure, shape, color, material, details of 90 Degree should be consistent with the standard of usability evaluation. There are two characteristics in 90 Degree, the first one is a transparent cover installed in front of the drill, which can collect the dust, rubbish when drilling and keep the work environment clean. So it is applicable for households. When the transparent cover of the drill is removed, it also can be used as a normal hand drill; the second one is the shape of 90 Degree makes it and the operating surface fitting together, thus enhancing the stability in operation, so it is best for inexperienced users. When 90 Degree contacts with the operating surface, it can emit the laser ray which helps the user to punch accurately, and make array punch more easily. After obtaining the data, charts, creating Shadow observation by the designers, they make a comprehensive evaluation on research results; verification advantages of 90 Degree meet the requirement of usability, reducing operating failure rate; and increasing safety factors. 90 Degree, in 2011, wined German Red Dot Design Award, which had become a representative excellent design example to resolve several drilling difficulties. The designers introduce ergonomics theory into design practice, and use scientific program and methods to evaluate the products which is useful to the development and promotion of products.

From Usability to Pleasure: A Case Study of Difference in Users’ Preference

For past decades, research of designing “pleasure” into products in the academic community has produced a multitude of evaluation models and frameworks. These models address the critical issues of pleasurable product design leading to emotional design. This study is intended to explore the change from the need of “usability” for the product design to the need of “pleasure” for the user experience. The questionnaires were used to obtain data from 343 subjects. The four keyboard designs were adopted in the experiment to study the difference and the change from “usability” to “pleasure” of users” preference. The results show that the need for pleasure is higher than usability, as well as attractive things also transmit the feel of work better. Besides, preference is related to gender, age, major, and educational background. Results presented herein provide designers with a valuable reference for examining the way how to design “pleasure” into product and the interactive experience of users in the design process.

Statistical Models for Web Pages Usability

The usability of an interface is a fundamental issue to elucidate. Many researchers argued that many usability results and recommendations lack empirical and experimental data. In this research, the usability of the web pages is evaluated using several carefully selected statistical models. Universities web pages are chosen as subjects for this work for ease of comparison and ease of collecting data. A series of experiments has been conducted to investigate into the usability and design of the universities web pages. Prototype web pages have been developed according to the structured methodologies of web pages design and usability. Universities web pages were evaluated together with the prototype web pages using a questionnaire which was designed according to the Human Computer Interactions (HCI) heuristics. Nine (users) respondents’ variables and 14 web pages variables (items) were studied. Stringent statistical analysis was adopted to extract the required information to form the data acquired, and augmented interpretation of the statistical results was followed. The results showed that the analysis of variance (ANOVA) procedure showed there were significant differences among the universities web pages regarding most of the 23 items studied. Duncan Multiple Range Test (DMRT) showed that the prototype usability performed significantly better regarding most of the items. The correlation analysis showed significant positive and negative correlations between many items. The regression analysis revealed that the most significant factors (items) that contributed to the best model of the universities web pages design and usability were: multimedia in the web pages, the web pages icons (alone) organisation and design, and graphics attractiveness. The results showed some of the limitations of some heuristics used in conventional interface systems design and proposed some additional heuristics in web pages design and usability.

基于人体工学的手动轮椅助力装置研究

针对我国失能、半失能老人使用非电动轮椅推行费力的现状,综合考虑使用者功能需求、使用环境与可行技术支撑三方面的要素,从动力系统可靠性理论计算、人体工学设计以及智能控制设计等方面开展研究,研发一款新型助力装置。该装置通过基于人体工学的集成优化设计实现了轻量化(≤5 kg)、小型化(390 mm×130 mm×140 mm)结构设计要求;创新地采用基于单手操作的快速挂接结构,实现了面向市面大部分手动轮椅的高适配要求和5 s内快速装卸的易操作要求;基于使用环境的动力学分析与设计实现了室内外行进20 km的续航里程要求;通过手环控制器和摇杆控制器的多元控制方式开发,实现了不同驱动人员对助力装置启停控制和速度控制的简易化操作要求。

基于网络评论文本分析的人机工学鼠标用户体验研究

探究人机工程学鼠标实际用户体验情况,分析其中的影响因素,梳理用户体验与可用性等方面关系。通过用户研究制作用户画像,将现有的鼠标以传统操作方式和新式人机操作方式为标准进行分类,共分出5种形式,总计10款被试产品进行研究。爬取现有人机工学鼠标相关商品网络评论,对评论文本及用户情绪进行分析。通过句意分析把握用户体验,并对评论进行语素提取,试图确定产品对用户体验的影响要素。最后,通过可用性测试与用户访谈对分析结果准确性进行验证与补充。得到产品网络评论文本分析结果与情绪分析数据,进而归纳用户实际体验。文本分析法与网络民族志的结合使设计师可以进一步挖掘用户信息,以用户为中心,对产品进行分析和评价,该方法对产品设计与优化均具有较强参考价值。

驾驶舱照明可用性综合评估方法及应用

驾驶舱复杂外部光环境易对飞行员造成视觉疲劳、行为、生理及情绪等不利影响。通过自动调光照明系统提高驾驶舒适性,保证飞行安全是提高驾驶舱人机工效水平的重要手段。本文提出一种典型外部光环境下驾驶舱照明系统的可用性综合评估方法。从有效性、效率、满意度三个维度对四种器件参数设置方案进行评估,采用层次分析法对显示器、指示灯、导光板、泛光灯四种自动调光器件重要性权重进行计算,得到驾驶舱可用性综合评分。本文提出的方法可以实现对驾驶舱自动调光照明系统的可用性定量评价,为飞机驾驶舱可用性系统优化设计提供依据。

基于舱外航天服手套基础性工效评价的人体力学指标优选研究

目的探索科学而实用的舱外航天服手套基础性工效评价的人体力学优选指标。方法从人体力学的力量、疲劳、感知觉、活动范围和灵活性5项指标(28项测定指标)对13名青年大学生(6女7男)进行了裸手与戴手套(舱外航天手套模拟件)的手动作业工效研究,并结合人体知识运用统计学方法对5项指标的测试指标进行了优选处理。结果可用握力代表力量,以主观疲劳与行为下降代表疲劳,以内收/外展、弯曲/伸展与旋转代表活动范围,形状感知代表感知觉,拧螺母打结代表灵活性。结论本文结果可为舱外航天手套的评价和性能改善提供基础性资料,具有一定实际意义和应用价值。

急性轻、中度低压缺氧对手动作业工效的影响

目的探讨急性轻、中度低压缺氧对手动作业工效的影响。方法利用低压舱模拟高空缺氧环境,设计4种客观工效项目(插钉板、拧螺母、形状感知和握力包括疲劳和耐力)和1种主观感觉项目(问卷),观察9名被试者在5种模拟高度(3500、4000、4500、5000、5500m)缺氧暴露(25±5)min手动作业工效的变化。结果与地面(50m,北京地区实际海拔高度)对照组相比,插钉板、拧螺母完成时间绩效在5种模拟高度均显著降低(P<0.01),在5000、5500m高度缺氧反应进一步加剧(P<0.001)。但在4500m高度时,绩效降低水平反低于4000m;形状感知反应时、反应时绩效和感知综合(反应时间与正确率综合)绩效在5种模拟高度均发生显著变化(P<0.01);握力绩效仅在4000、5500m显著降低(P<0.05),疲劳绩效在5种模拟高度均未发生显著改变,耐力绩效(最大握力和疲劳综合绩效)在5000、5500m高度显著降低(P<0.05);主观测试项目在5种模拟高度均发生了显著变化,且随高度增加,主观感觉分值也相应增加。结论急性轻、中度低压缺氧对手动作业工效产生显著的负面影响。插钉板、拧螺母、形状感知和主观问卷调查4种工效测试项目对缺氧比较敏感,在5种模拟高度其工效均显著降低;耐力绩效对缺氧不敏感,仅在5000、5500m模拟高度显著降低。

航天器人控交会对接系统工效学要求与评价技术研究及实践

从人-系统整合的角度分析提出了工效学要求指标体系,通过试验研究确定了工效学要求,基于小样本理论和可靠性试验方法建立了复杂人控回路工效学评价方法。对人控交会对接系统工程设计开展了系统级评价试验,重点评估了航天器显控系统与人的能力匹配性;结合神舟八号与天空一号自动对接过程中下传的电视图像分析确定了人控交会对接适宜的光照环境;通过神舟九号和神舟十号载人航天飞行任务中人控交会对接试验,验证了工效学要求的合理性和工效学评价结果的正确性。最后提出了我国空间站任务阶段航天器人控交会对接系统工效学研究的重点。

食品生产包装作业的人机工程学分析

目的对食品生产包装作业进行基于人机工程学的分析和改进。方法采用计算机辅助人机交互评估系统软件SIMMIE,对食品生产包装作业的捏合动作和包装动作进行生物力学分析,并根据力学结果对工作环境进行结构改进。结果改进后人体受力明显减少。结论基于人机工程学的研究方法为轻体力作业工作环境设计提供了一定的依据和规范。

基于工效评价的手动作业活动范围研究

目的探索完善而合理的手动作业活动范围评价指标及最大主动活动范围。方法根据手的活动机理和手动操作特点,提出了较为全面的手动作业活动范围评价指标,并通过26名青年大学生(12女14男)对16项测定指标进行了测试。结果得到拇指、其余4指及手腕3部分的最大主动活动范围。结论本文结果可为舱外航天手套工效学设计提供基础。

输液泵工效学设计研究

医疗器械在现代社会中已得到了广泛的应用。在发生的医疗事故中,医疗器械本身设计缺陷和使用者的使用错误占据了一定比例。工效学作为提高医疗器械质量的重要手段之一,可以大大降低医疗事故的发生率。本文从医疗器械工效学设计的相关的标准出发,提出了改进的工效学设计车轮模型和可用性模型,并将这两种模型应用到输液泵的设计过程中,实验结果表明按照工效学设计的医疗器械更为高效。

电脑指向设备易用性测试方法研究

随着图形界面(GUI)在视屏作业中的大量使用,电脑用户已经很大程度上依赖于指向(Pointing)设备(比如鼠标)进行控制和操作。本项研究尝试研发电脑指向设备易用性测试方法,以更好的从工效学角度研究办公室视屏作业中的指向活动。指向设备易用性测试方法设计包括:标准化的指向测试;一系列能够准确描述指向的参数;用户满意度问卷。为了验证本测试方法,对具有代表性的笔记本电脑外接鼠标和内置触摸板进行了实验性的易用性测试。20名实验对象使用这两种设备完成了标准化的指向测试和满意度问卷。实验数据分析表明本指向设备易用性测试方法准确、有效。

手动抓握结构的人机适配性实验研究

目的通过实验研究,确定手工搬运重物时手动抓握结构的工效学设计要求和测评方法。方法通过用户使用习惯调研和人机交互行为分析,提炼出抓握结构的工效学设计和测评指标,应用目标用户进行典型结构样件的实际使用体验测试,并辅以虚拟仿真的方法对实验结果进行验证。结果获得满足手工搬运者搬运安全性和舒适性要求的抓握结构形状尺寸及位置的工效学设计要求。结论为手动抓握结构的工效学设计及评价提供参考。

美国NIOSH手工提举方程在中国的验证研究

目的总结国家标准GB/T31002.1的验证性实验研究过程,以指导国家标准的推广与应用。方法采用心理物理学法获取健康青年人不同提举高度、频率与水平距离下的最大可接受质量(Maximum acceptable weight of lift,MAWL),并分析MAWL与NIOSH手工提举方程质量推荐限值(RWL)间的差异。结果MAWL随三提举参数的增大呈显著降低趋势,多数RWL高于中国青年人的手工提举重物能力。结论国内青年人群应用NIOSH手工提举方程时,可通过调整提举高度系数与降低负荷常量予以修正。

家用手电钻设计创新中人因工程价值的导入

研究背景本设计研究就来源于鲁迅美术学院工业设计实验研究中心,它是中国工业设计领域唯一所国家级实验中心。在实验中心设计人员研究产品创新的方法,将人体功效学理论导入到产品设计实践之中。同时实验中心拥有三维快速打印设备、数控加工中心、平面雕刻设备等仪器,可以帮助设计人员使用不同的材料制作概念产品的实验模型。这些实验模型用于测试产品是否符合人体功效学的要求。因此,设计人员在进行各项设计创新时会在实验中心进行各项人机工效学实验。实践创新家用手电钻是针对居家使用环境,为没有使用电钻经验的使用者,如妇女、老人也能轻松自如地完成各项操作而设计的,确保操作安全并辅助使用者解决精确打孔、定位、收纳杂屑等操作。通过对了解或熟练操作手电钻的用户调研,发现以用户为中心的使用问题,并综合产品创新性设计方法提出解决方案。本文试图通过使用者行为记录与分析系统,对适用的受试者人群进行双手操作分析、使用姿态分析、细节工作分析、时间与动作研究等人因工程研究;同时通过用户体验分析、行为意向分析等方式进行使用者主观感性评估。信息来源家用手电钻的使用功能、组成结构、形态造型、色彩、材质、细节等因素符合易用性评估标准。家用手电钻有两个设计特点,第一个是电钻前端的透明罩,可以收集打孔产生的灰尘、垃圾,保持工作环境清洁;第二个是电钻前端的形状使电钻与打孔面完全贴合,可以增强打孔稳定性。所以这款手电钻非常适合于无使用经验者,电钻在使用时可在打孔面上投射辅助线,帮助用户进行精确打孔和阵列打孔。研究结果经测评得到的数据、图表,并自创了重影叠加方法对研究成果进行综合评估,验证了家用手电钻所具有的优势符合易用性使用需求,减少了操作失误率,增加了使用安全性因素。结论这款家用手电钻被命名为"90 Degree",在2011年获得德国红点概念设计奖,成为了具有代表性的解决多种手电钻使用困难的优秀设计范例。将人因工程理论导入设计实践,用科学的测评程序与方法来评估产品所具有的价值,而这一过程有利于产品的深入研发和推广。

台湾地区与工作相关之肌肉骨骼损伤调研与管控

肌肉骨骼损伤是普遍的职业安全与健康问题。自上个世纪90年代以来台湾劳动与职业安全卫生研究所与人因工程领域科研人员即持续投入职场肌肉骨骼损伤方面的调研,这些调研包括以问卷来分析各类产业劳工肌肉骨骼损伤症状之比例、种类、身体部位、及严重性之流行病学调查、以现场观察与纪录之现场人因性风险评估、及实验性人工物料处理活动研究。台湾已公告实施的「职业安全卫生法」则将肌肉骨骼损伤问题的分析与管控列为对企业之强制性要求。职场肌肉骨骼损伤风险评估工具的持续开发与改善、相关教材的编撰、及专业人才的培训是未来发展的重点。

人因工程学在工业设计中的应用研究

文章从人机交互及可用性应用、生理工效学应用、虚拟现实及人机界面应用等三个方面,分析了人因工程学在工业设计中的应用。

几款空调产品使用说明书工效学测评研究

使用说明书被称作家用电器产品的"软质量",它直接影响着消费者产品的购买和安全使用。本文以家用空调使用说明书为例,从工效学角度对几款空调使用说明书进行可用性评测,着重对说明书在使用过程中存在的工效学问题进行了研究和分析,并提出了相应的解决方案,研究结果为今后提升空调产品使用说明书的用户体验水平提供了重要参考和指导。