Ergonomic keyboard design

Abstract

The design of keyboards is still characterized by that of mechanical typewriters. This paper presents a summary of a research project dealing with the ergonomic improvement of keyboards, carried out at the IAO in Stuttgart during the past five years. Extensive laboratory evaluation of experimental keyboards, where different design parameters were tested under real life conditions, have produced a relative optimum regarding ergonomic keyboard design. An accompanying investigation of user acceptance evaluated all realized parameters. In co-operation with a keyboard manufacturer, the results were used to design a marketable product, which may be seen as an important contribution to ergonomic keyboard design.     

Ergonomic aspects of aircraft keyboard design: the effects of gloves and sensory feedback on keying performance

Increasing requirements for aircraft keyboards have indicated inadequacies in ergonomic standards for airborne environments, in particular for tasks involving unskilled, discontinuous data entry, with emphasis on accuracy rather than speed. Four experiments are reported from a programme of research aimed at the development and application of methodologies for assessing factors relevant to keyboard design. Experiment 1 demonstrated that the effects of various aircrew gloves on a representative aircraft data entry task are highly situation specific. Experiment 2 showed that gloves impaired performance on a high compatibility continuous keying task, with relatively high keying rates, and that this impairment was not reduced by additional auditory feedback. Experiment 3 demonstrated that the high compatibility keying task provided a successful methodology for investigating the effects of key displacement and resistance on speed and accuracy. Experiment 4 indicated the relative contributions of reduced tactility and mobility to the effects on keying and manipulative performance caused by aircrew gloves. Together, these experiments suggest that kinaesthetic and tactile feedback associated with keying are relatively unaffected by aircrew gloves, and that restrictions on mobility caused by gloves may be more important for continuous data entry involving relatively high keying rates     

一种PC键盘的革命性设计

本文即介绍一种新型PC键盘--掌心键,可将其置于手掌中,单手五键组合操作,自带LCD显示,内置嵌入式系统,支持中英文输入法,升级容易,解决现PC键盘反手疲劳操作的问题,还解决双手按键、鼠标难以同时操作的问题.该键盘的应用,将结束当前PC键盘的单一模式的局面,同时可引导键盘多样化、个性化的发展.     

Ergonomic studies in computer-aided design

This paper describes the results of an ergonomic survey on interactive graphics workstations for computer-aided design (CAD). A work-sampling study was carried out to characterize the use of keyboard, digitizer tablet and video display. Subjective impressions of CAD software, CAD hardware and health aspects were collected by means of a questionnaire. Working methods and working postures were recorded on videotape. The two most important differences in comparison with other office terminals are: (i) dynamic working methods result in an absence of constrained postures in CAD operators and allow full-body exercise; (ii) CAD operators spend more time (46-68 per cent of working hours) viewing the video display than the average office terminal operator. Some ergonomic recommendations have been deduced for the construction of CAD terminals, as well as for the ergonomic improvement of existing workstations.     

Ergonomic principles and map design

Ergonomic principles have seldom been applied to the design of maps for use in aviation. Maps are not usually evaluated as displays of information, and the contents of maps often do not match the needs of the user. Most maps are visually so complex that it is not immediately apparent whether standard recommendations for the coding and display of information apply to them. Methods for evaluating maps have to be devised, and comparisons made between subjective and objective measures. A series of experiments has considered the content of maps in relation to the needs of the users, and has examined new methods for presenting information on maps, with a view to increasing the efficiency of map communication.     

Ergonomic studies in computer-aided design

Abstract

This paper describes the results of an ergonomic survey on interactive graphics workstations for computer-aided design (CAD). A work-sampling study was carried out to characterize the use of keyboard, digitizer tablet and video display. Subjective impressions of CAD software, CAD hardware and health aspects were collected by means of a questionnaire. Working methods and working postures were recorded on videotape. The two most important differences in comparison with other office terminals are: (i) dynamic working methods result in an absence of constrained postures in CAD operators and allow full-body exercise; (ii) CAD operators spend more time (46–68 per cent of working hours) viewing the video display than the average office terminal operator. Some ergonomic recommendations have been deduced for the construction of CAD terminals, as well as for the ergonomic improvement of existing workstations.     

Ergonomic design of large forestry machines

Since 1967, the ergonomic design of large forestry machines has been the subject of continuous study. Ergonomic guidelines have been developed and successfully introduced to the manufacturers of the machines and to the forest industries.

Manufacturers have implemented comprehensive ergonomic improvements. Operator workspace, visibility, lighting, operator's seats, mounting and alighting, cab climate, and service of machines have been improved. Noise and vibration levels have been reduced. The risk of accidents is slight. In many respects, the ergonomic standard is now good.

Increasing mechanization is posing new problems, however. Operators of forestry machinery are being afflicted by overload injuries to the neck, arms, and cervical spine. The main causes of these injuries are probably excessive periods of sitting, excessive work intensity during work in fixed, ergonomically inappropriate positions, and repetitive, short-cycle movement patterns. Ergonomic improvements in equipment design (particularly controls) and work organization are proposed in this report.     

Ergonomic design in ancient Greece.

Although the science of ergonomics did not actually emerge until the 20th century, there is evidence to suggest that ergonomic principles were in fact known and adhered to 25 centuries ago. The study reported here is a first attempt to research the ergonomics concerns of ancient Greeks, on both a conceptual and a practical level. On the former we present a collection of literature references to the concepts of usability and human-centred design. On the latter, examples of ergonomic design from a variety of fields are analysed. The fields explored here include the design of everyday utensils, the sculpture and manipulation of marble as a building material and the design of theatres. Though hardly exhaustive, these examples serve to demonstrate that the ergonomics principles, in content if not in name, actually emerged a lot earlier than is traditionally thought.     

矩阵键盘驱动电路的高阻设计

矩阵键盘是人机交互的重要设备。实际应用场景中,用户通过键盘按键产生激励信号,经过驱动电路送到扫描电路,最终传给处理器电路,从而完成人机交互。在这个过程中,驱动电路负责传递信号,驱动电路的设计决定着整个系统能否正常工作。在驱动电路中引入高阻设计后,可以避免多个按键同时按下时矩阵键盘内部电路发生短路的情况,能让整个驱动电路更加可靠。     

控制台人机界面设计初探

针对某系统控制台的功能要求,讨论了人机界面的设计过程。利用数字化技术开发应用程序,依据人机工程的基本原理,将原有的各种硬件设备集成为单机工作台。从人机交互界面的风格设计、布局分析,媒体选择、操作设计等几方面进行了初步探讨。从用户的角度出发,在满足功能需求的情况下着重实现了界面的友好性和易操作性。     

A case study in iterative keyboard design using participatory design techniques

Replacing a keyboard can be stressful for operators who take calls all day, particularly when special functions must be sacrificed. This study applied several participatory design techniques to involve over 3,000 operators in the redistribution of function keys on their replacement keyboard. Video analysis and manual data logging methods were surprisingly accurate when measured against software logs. User acceptance was excellent. In the initial cutover program, operator performance levels returned to normal very quickly, resulting in over-confidence and unrealistic expectations of post-implementation performance for the remaining call centres because the focus was on the technology rather than on the impact of technology on business benefits. As a consequence, business plan requirements for future projects have now been changed to accommodate predictions of post-implementation performance and taking into account other changes happening at the same time.     

Ergonomic design and evaluation of new surgical scissors

The purpose of this study is to design a new surgical scissors handle and determine its effectiveness with various usability indices. A new scissors handle was designed that retains the professional grip but has the shapes of the eye rings modified to fit the thumb and ring finger and finger rests for the index and little finger. The newly designed scissors and traditional scissors were compared by electromyography, subjective evaluation and task performance in experiments using cutting and peeling tasks. The newly designed scissors reduced muscle load in both hand during cutting by the closing action, and reduced the muscle load in the left hand during peeling by the opening action through active use of the right hand. In evaluation by surgeons, task performance improved in addition to the decrease in muscle load. The newly designed scissors used in this study demonstrated high usability.

Practitioner Summary: A new scissors handle was designed that has the eye rings modified to fit the thumb and ring finger. The newly designed scissors reduced muscle load and enabled active use of the right hand. In evaluation by surgeons, task performance improved in addition to the decrease in muscle load.     

Ergonomic design interventions--a case study involving portable ladders

Portable ladders are one of the most ancient tools conceived by man. They remain ubiquitous and indispensable even today. It is interesting to note that there is little difference between the makeshift portable ladders used throughout history and some still used today. The design of portable ladders seems to have simply evolved, rather than been subject to formal design process, including ergonomic criteria. An analysis of 277 fatalities associated with ladders was conducted to describe the pattern of ladder fatalities and identify and assess ergonomic design controls. All ladder fatalities analysed were found to contain multiple human, equipment (ladder) and environmental causative factors. It is hypothesized that significant gains with regard to reducing future fatalities can be achieved by applying ergonomic design principles to ladders to accommodate predictable and undesirable human behaviour. Without effective future change, the only prediction that can be made is that the pattern of ladder fatalities will simply continue.     

Ergonomic design visualization mapping- developing an assistive model for design activities

Ergonomic models and techniques are a fundamental issue in the design of comfortable and safe products and spaces. User studies, related to visualization tools are current issues in the ergonomics and design visualization literature. But researchers have begun to discover that user study is rarely straightforward, especially when drawing visualization data from interdisciplinary sources. The availability of a plethora of visualization techniques can make it difficult to determine the most appropriate technique to convey maximum possible understanding.The RT-MHV (“Real-time”– “Motion history volumes”) 3D computerized assessment model, developed by the authors, demonstrates a local risk evaluation of work-related musculoskeletal disorders (WMSDs), based on real-time and on motion history volumes. With the model, the visual display of the WMSD risk level for each body segment is defined by color-coding at points surrounding an avatar's segment, representing an actual user. The values associated with areas with an increased risk of WMSDs can be identified and iterated quickly, so as to determine the “optimal posture”. Designers can share this knowledge by recording the user's postural interactions, defined through the mapping of geometric comfort data and WMSD risk level categories.The challenge in the development process was to overcome existing “gaps” between ergonomics data and designer requirements. Further research on the RT-MHV model is recommended, principally for developing stand-alone CAD software. An aggregated statistical information database and complete body joints visualizations will be computerized in due course. 2D tabulation and statistical information relating to body joints will be made available on demand.     

Ergonomic field analysis of the software design workstation

Abstract

This research has been carried out in order to verify in the field the exigencies yielded by a particular task and report indications for the ergonomic optimization of the relevant workstation. The task under examination was software design executed by 127 subjects in different environments. The steps in which this research was carried out were as follows: analysis of the task; analysis of subjects; analysis of the workstation and environment; and observations on 24 subjects representative of the population. The observations were in order to discover the level of posture variability and establish the physical parameters to be optimized. Results show that, for the activity examined, the heaviest restrictions imposed by the hardware refer to the eye-screen distance, head movement and curvature of the trunk. Therefore, the physical parameters to be optimized are height, width and depth of the table, and height and design of the chair.     

基于图像识别的无键盘电子锁设计

锁一直是人们生活的必需品,随着社会经济和科学技术的发展,人们对锁的安全及方便性提出了更高的要求。应用ARM技术结合图像识别设计了一种电子锁,该锁通过摄像头采集密钥信息,控制器解码信息并对密钥进行验证。系统部件少,硬件依赖性低,可移植性高,易于使用,并能不断更新解锁方式。