A comparative study of gestural, keyboard, and mouse interfaces

This paper presents results from three experiments which compared gestural, keyboard, and mouse/keyboard interfaces to a spreadsheet program. This is the first quantitative comparison of these types of interfaces known to the author. The gestural interface employed gestures (hand-drawn marks such as carets or brackets) for commands, and handwriting as input techniques. In one configuration, the input/output hardware consisted of a transparent digitizing tablet mounted on top of an LCD which allowed the user to interact with the program by writing on the tablet with a stylus. The experiments found that participants were faster with the gestural interface than with the keyboard or mouse/keyboard interface. In addition, subjects tended to prefer the gestural interface over the keyboard interface. Inexperienced mouse users also tended to prefer the gestural interface over the mouse/keyboard interface, although experienced mouse users preferred the mouse. The main difficulties with the gestural interface had to do with poor display legibility and problems with the stylus. The benefits of the gestural interface are explained in terms of the fewer number of steps required to carry out an operation, the greater ease of remembering gestural commands, and the ability to focus on a single surface for input and output.     

Design and evaluation of small,linear QWERTY keyboards

Miniature keyboard design is motivated by the need for smaller mobile devices with maximum user display area. Thus, this study developed four miniature keyboard designs which varied from conventional keyboard design in terms of their configuration and layout. The purpose of this study was to evaluate the input speed, accuracy, comfort, likability and learnability of four miniature keyboards. Sixteen fast typists and 16 slow typists were recruited to use these four miniature keyboards. The results showed that the rectangular-shaped keycaps of 3 letters with separated keycaps of numerals obtained the best proficiency speed, highest comfort and greatest user acceptance among the four keyboards. Moreover, the keyboards with square-shaped keycaps had better input accuracy compared to rectangular-shaped keycaps. Finally, the proposed keyboards were smaller than current keyboards, and the performance for all of the small keyboards was worse than that of the conventional keyboard.     

A study of the usability of handwriting recognition for text entry by children

This paper describes a pilot study that investigated the usability of handwriting recognition for text entry in a free writing activity. The study was carried out with eighteen children aged 7 and 8; each used three different writing methods to construct short pieces of text. The methods used were; pencil and paper, the QWERTY keyboard at a computer, and a pen and graphics tablet. Where the pen and graphics tablet was used, the handwritten text was recognised by the software and presented back to the children as ASCII text. Measures of user satisfaction, quantity of text produced, and quality of writing produced, were taken. In addition, for the handwritten work, the recognition process was evaluated by comparing what the child wrote with the resulting ASCII text. The results show that the children that took part in the study generally produced lengthier texts at the graphics tablet than at the QWERTY keyboard but that the non-technical solution, the pencil and paper was, in this instance, the overall best method for composing writing. To further the debate on the possibilities for digital ink and tablet technologies, key usability problems with the handwriting recognition interface are identified and classified, and solutions to these usability problems, in the form of design guidelines for both recognition-based and pen-based computer writing interfaces, are presented. Additionally, some reflections on how studies of text input and free writing composition can be evaluated are offered.     

Evaluation of text input mechanisms for wearable computers

This paper reports on an experiment investigating the functionality and usability of novel input devices on a wearable computer for text entry tasks. Over a 3-week period, 12 subjects used three different input devices to create and save short textual messages. The virtual keyboard, forearm keyboard, and Kordic keypad input devices were assessed for their efficiency and usability in simple text-entry tasks. Results collected included the textual data created by the subjects, the duration of activities, the survey data and observations made by supervisors. The results indicated that the forearm keyboard is the best performer for accurate and efficient text entry while other devices may benefit from more work on designing specialist graphical user interfaces (GUIs) for the wearable computer.     

Effect of horizontal position of the computer keyboard on upper extremity posture and muscular load during computer work

The distance of the keyboard from the edge of a work surface has been associated with hand and arm pain; however, the variation in postural and muscular effects with the horizontal position have not been explicitly explored in previous studies. It was hypothesized that the wrist approaches more of a neutral posture as the keyboard distance from the edge of table increases. In a laboratory setting, 20 adults completed computer tasks using four workstation configurations: with the keyboard at the edge of the work surface (NEAR), 8 cm from the edge and 15 cm from the edge, the latter condition also with a pad that raised the work surface proximal to the keyboard (FWP). Electrogoniometers and an electromagnetic motion analysis system measured wrist and upper arm postures and surface electromyography measured muscle activity of two forearm and two shoulder muscles. Wrist ulnar deviation decreased by 50% (4 degrees ) as the keyboard position moved away from the user. Without a pad, wrist extension increased by 20% (4 degrees ) as the keyboard moved away but when the pad was added, wrist extension did not differ from that in the NEAR configuration. Median values of wrist extensor muscle activity decreased by 4% maximum voluntary contraction for the farthest position with a pad (FWP). The upper arm followed suit: flexion increased while abduction and internal rotation decreased as the keyboard was positioned further away from the edge of the table. In order to achieve neutral postures of the upper extremity, the keyboard position in the horizontal plane has an important role and needs to be considered within the context of workstation designs and interventions.     

Effect of horizontal position of the computer keyboard on upper extremity posture and muscular load during computer work

The distance of the keyboard from the edge of a work surface has been associated with hand and arm pain; however, the variation in postural and muscular effects with the horizontal position have not been explicitly explored in previous studies. It was hypothesized that the wrist approaches more of a neutral posture as the keyboard distance from the edge of table increases. In a laboratory setting, 20 adults completed computer tasks using four workstation configurations: with the keyboard at the edge of the work surface (NEAR), 8 cm from the edge and 15 cm from the edge, the latter condition also with a pad that raised the work surface proximal to the keyboard (FWP). Electrogoniometers and an electromagnetic motion analysis system measured wrist and upper arm postures and surface electromyography measured muscle activity of two forearm and two shoulder muscles. Wrist ulnar deviation decreased by 50% (4°) as the keyboard position moved away from the user. Without a pad, wrist extension increased by 20% (4°) as the keyboard moved away but when the pad was added, wrist extension did not differ from that in the NEAR configuration. Median values of wrist extensor muscle activity decreased by 4% maximum voluntary contraction for the farthest position with a pad (FWP). The upper arm followed suit: flexion increased while abduction and internal rotation decreased as the keyboard was positioned further away from the edge of the table. In order to achieve neutral postures of the upper extremity, the keyboard position in the horizontal plane has an important role and needs to be considered within the context of workstation designs and interventions.     

The MOD Keyboard

A special plug-in cartridge for the VIC-20 converts it into a dynamic keyboard emulator that enables a handicapped user to control a second, unmodified computer.     

User errors on scanning keyboards: Empirical study, model and design principles

Scanning keyboards are used as augmentative communication aids by persons with severe speech and motion impairments. Literature reports two approaches for the design of scanning keyboards; design based on the experience and intuition of designers and user model based design methods. None of these approaches, however, considers user errors in the design process, potentially limiting the practical usefulness of the designs. We have performed experiments in order to study user errors on scanning keyboards. We have found that two types of errors affect performance of scanning keyboard users significantly, namely (a) timing error that occurs when a user fails to select a key at the appropriate time and (b) selection error that occurs when the user selects a wrong key. These errors have been found to increase users’ text entry time by as high as 65% and 35%, respectively. Based on empirical observations, we have developed a state transition model of user behavior during user–keyboard interaction. The model comprises of four states, each of which represents the physical and cognitive state of the user at particular instant of the interaction. The transitions are caused by users’ physical, cognitive and perceptual activities. We have found that the errors could be explained as caused due to the problems in making the transitions properly. In addition to explaining errors, the model has helped us to predict distribution of error probabilities with respect to the distance between keys. We have used the model predicted error distributions to develop principles for scanning keyboard design that aim to reduce user errors. The principles state that the frequently used key pairs should be placed apart by a minimum distance, which has been obtained from the error distributions, in order to reduce errors. The method and results of the study, the user model and the design principles are presented in this paper.     

智能人机界面Agent的用户模型及其构建方法

智能Agent是计算机领域中自适应人机界面需要研究的关键问题之一。文章论述了智能Agent的定义、功能和组成。给出了用户模型的结构框图,探讨了用户模型及其构建方法,并通过实例介绍了几个典型的智能Agent系统。     

芯片模拟仿真方法——5.组合模拟仿真软件设计实例

本讲介绍如何用Pascal语言在PC机上模拟MCS-51单片机的指令系统,用PC机的存储器和文件系统模拟单片机的硬件环境,再借助于PC机的键盘和显示器构成一个方便用户调试程序的交互面、多窗口及菜单选择的开发环境。     

On the implications of user variability in open systems An overview of the little we know and of the lot we have to find out

As the use of computers increases, the cost of educating computer users rises. Therefore the need for extensive education of users should be avoided as much as possible. Instead computer systems should be adapted to the requirements and characteristics of computer users. Hereby the need to identify user characteristics arises. The less computer educated the users, the more their requirements of the systems will differ. Where user characteristics are difficult to change, it will be worthwhile to attend to user differences in the design of systems. The implications of user differences may vary depending upon the type of task to be performed. The present paper presents an analysis of different user characteristics and their possible interactions with different task requirements. Hereby some recommendations regarding the need to educate users or adapt systems to the user were derived.     

三维视景仿真系统中仿真过程管理的研究

三维视景仿真系统的仿真过程管理一直是计算机图形学领域的热点之一。三维视景仿真系统的研究主要集中在虚拟环境的真实性方面,仿真过程管理的研究还没有被很好地解决。文中按照功能将三维虚拟视景仿真系统分为七个模块：数据输入、键盘输入、配置文件、消息映射、场景控制、仿真环境显示、数据记录;又从用户角度划分出三个模块：输入模块、处理模块和输出模块。同时,文中提出了配置文件和三维模型XML描述两种关键方法,分别用来存储仿真环境相关数据和简化模型调用方式,提高了虚拟仿真系统的通用性。此方法在三维视景仿真系统的开发过程中成功地进行了应用。     

An evaluation of stylus-based text entry methods on handheld devices studied in different user mobility states

Effective text entry on handheld devices remains an important user input problem. On a personal digital assistant (PDA), text entry methods traditionally support stylus-based input performed by the user’s dominant hand. In this paper, we present the design of a two-handed software keyboard for a PDA which specifically takes advantage of the thumb in the non-dominant hand. We compare our chorded keyboard design to other stylus-based text entry methods in an evaluation that studies user input in different user mobility states. Our study shows that users type fastest using the mini-qwerty keyboard, and most accurately using our two-handed keyboard. We also discover a difference in input performance with the mini-qwerty keyboard between stationary and mobile states. As a user walks, text input speed decreases while error rates and mental workload increases; however, these metrics remain relatively stable in our two-handed technique despite user mobility.     

POLYPLOT—an interactive modular program in basic for plotting graphs

POLYPLOT is an interactive program in BASIC, with a modular structure, for plotting x-y graphs on a conventional printer. The options offered by POLYPLOT are: input of data from keyboard or disk file: single parameter or combination of parameters assigned to each axis; log plots: best-fit line and polynomial curve fitting; program scaling or user scaling of the axes; replotting of a data set, excluding samples, either individually or in groups. POLYPLOT may be used to create a large number of different programs because each option is contained in program modules which may be merged into a central program framework as required. The options operate independently so that programs containing any combination of options may be created.     

A display package for CAD of control systems

A multi-access computer system has been installed at the Control Systems Centre of the University of Manchester Institute of Science and Technology. The application of this computer to research into the computer aided design of industrial control systems involved the connection of two keyboard display terminals to the system. The ARDS storage tube displays chosen had the advantages of being teletypewriter compatible and not requiring the connection of a satellite computer A graphics package for the entry and structuring of data derived from the stability analysis of control systems was required as soon as possible after the installation was commissioned. The initial package enabled data to be entered by program and then selected and plotted by keyboard requests. Translation, scaling, alteration of the method of plotting (with points or vectors) and the selection of different items for the display were all carried out by keyboard interaction For long term CAD work a more extensive graphics package was required, the specification was determined following feedback from users of the initial package. It provided additional facilities for graphic interaction, alphanumeric annotation of the displays, specialized drawing and data entry functions and the storing of any pictures built up by the user, as well as a more linked data structure. The structure and facilities of this package are described.     

On the implications of user variability in open systems An overview of the little we know and of the lot we have to find out

Abstract

As the use of computers increases, the cost of educating computer users rises. Therefore the need for extensive education of users should be avoided as much as possible. Instead computer systems should be adapted to the requirements and characteristics of computer users. Hereby the need to identify user characteristics arises. The less computer educated the users, the more their requirements of the systems will differ. Where user characteristics are difficult to change, it will be worthwhile to attend to user differences in the design of systems. The implications of user differences may vary depending upon the type of task to be performed. The present paper presents an analysis of different user characteristics and their possible interactions with different task requirements. Hereby some recommendations regarding the need to educate users or adapt systems to the user were derived.     

Dietary intake recorder based upon a single-board microcomputer

A food recording electronic device to simplify the collection of dietary data is described. The need for a subject to maintain a quantitative account of food intake, and for a dietitian to subsequently code this record prior to computer analysis, are both eliminated using this approach. In combination with an electronic kitchen balance, the recorder, which is based upon a single-board computer (SBC) and special keyboard, enables the weight, food type and time of consumption of each food to be recorded automatically in response to simple key entry. The resident program, transparent to the user, allows data from surveys lasting up to three weeks to be stored for subsequent serial downloading to a host computer.     

基于单片机的简易电子琴的设计与实现

电子琴是现代电子科技与音乐结合的产物,是一种新型的键盘乐器。它在现代音乐扮演重要的角色,单片机具有强大的控制功能和灵活的编程实现特性,它已经溶入现代人们的生活中,成为不可替代的一部分。该文的主要内容是用8253芯片为核心控制元件,设计一个简易电子琴。通过按动STAR ES598PCI单板机的G6区的1~7号键,使用单板机上的8255A芯片进行音调的选择,由8253芯片控制产生不同频率的方波,输出到单板机上D1区的蜂鸣器,使其对应于G6区的1~7号键由低到高发出1~7的音阶,并由8255A芯片控制8253芯片的工作状态,使其能够控制蜂鸣器的发声与否,从而实现简易电子琴的演奏功能。同时,也可以通过事先设置好的“乐谱”回放一段音乐,实现简易电子琴的回放功能以及对用户演奏过的一段音乐进行重放功能。用户可以通过DOS界面下的菜单对电子琴的回放和重放或是演奏功能进行选择。     

The Reactive Keyboard: a predictive typing aid

The Reactive Keyboard, a device that accelerates typewritten communication with a computer system by predicting what the user is going to type next is described. The version described is designed for entering free text and runs on any Apple Macintosh computer with at least 1 MB of memory (though 2 MB is preferred). It makes full use of the Macintosh mouse-and-window environment to give users convenient control over display and acceptance of predictions, and it requires no physical keyboard. The interface increases the speed and ease of communicating with a computer, especially for physically disabled people