不同视觉反馈对笔倾斜输入性能的影响

针对笔倾斜输入过程中存在遮挡、视角错觉和缺乏反馈等问题,分析了视觉反馈的增加对笔倾斜输入性能的影响.首先结合笔倾斜的特点设计了图形全跟踪、图形部分跟踪、图形无跟踪、数字全跟踪、数字部分跟踪和数字无跟踪6种不同的笔倾斜视觉反馈;然后通过对比实验考察了经过视觉反馈后,在直接和间接设备上完成不同角间距的目标选择任务时笔倾斜输入的性能.实验结果表明,视觉反馈可以有效地提升目标选择的速度,而跟踪机制可以有效地提高目标选择的准确度;图形反馈的速度快于数字反馈;全跟踪反馈的错误率低于部分跟踪反馈;在直接设备上完成目标选择任务速度快,但在间接设备上完成目标选择任务的准确度更高.最后给出了笔倾斜输入和视觉反馈的使用原则和建议,对笔式界面中的笔倾斜交互和视觉反馈设计具有指导意义.     

屏幕区域对笔通道输入性能的影响

针对笔通道输入在不同屏幕区域上的差异,分析了屏幕区域对笔通道输入的影响.首先设计了轨迹非受限的书写和轨迹受限的划动2种不同的笔式输入实验任务,然后在WacomCintiq21UX上展开实验并对比考察了笔通道输入在不同屏幕区域的性能.实验结果表明,以屏幕一角为极点所形成的极坐标系中,笔通道值随极径的增加而增大,笔通道值与极径之间呈幂函数关系或线性关系;各笔通道值的极值通常出现在屏幕的角落区域;对以右手为惯用手的用户来说,屏幕上侧的笔倾斜角通常大于屏幕下侧的笔倾斜角,笔的方位角随屏幕区域位置呈顺时针减小再增加的趋势;屏幕被划分的数量和屏幕上的不同区域位置均对交互性能存在显著影响;随着屏幕区域划分数量的增加,各区域之间的均值差异减小;结合划动速度、脱离错误率、偏出轨道率和偏离中线值,中部区域的综合性能优于四周区域,小尺寸区域的综合性能优于大尺寸区域,上侧区域的综合性能优于下侧区域.最后给出了面向屏幕区域的交互设计建议,为面向屏幕区域的笔通道交互提供了参考依据.     

笔方位及与笔倾斜的混合输入

针对传统笔式设备输入能力有限的问题,引入笔方位并考查其性能及其与笔倾斜的混合使用.首先设计笔方位目标选择和笔方位与笔倾斜混合目标选择2个实验;然后采用组内重复方法展开实验,考查笔方位及其与笔倾斜混合输入的性能.实验结果表明,正方向的笔方位输入优于斜方向; 30°, 60°和90°笔方位容限划分下,分别形成了6个、4个和1个速度一致区间;笔方位和笔倾斜划分越密集,用户完成目标选择任务的难度越大;当笔方位容限区间为60°且笔倾斜容限区间为20°时达到最优的划分.最后给出笔方位与笔倾斜混合使用的建议和应用场景,为基于方位和倾斜的笔式交互技术设计提供了参考依据.     

移动手持环境下触摸式目标选择技术对比

目的触摸输入方式存在"肥手指"、目标遮挡和肢体疲劳现象,会降低触摸输入的精确度。本文旨在探索在移动式触摸设备上,利用设备固有特性来解决小目标选择困难与触摸输入精确度低的具体策略,并对具体的策略进行对比。方法结合手机等移动式触摸设备所支持的倾斜和运动加速度识别功能,针对手机和平板电脑等移动式触摸输入设备,实证地考察了直接触摸法、平移放大法、倾斜法和吸引法等4种不同的目标选择技术的性能、特点和适用场景。结果通过目标选择实验对4种技术进行了对比,直接触摸法、平移放大法、倾斜法、吸引法的平均目标选择时间,错误率和主观评价分别为(86.06 ms,62.28%,1.95),(1 327.99 ms,6.93%,3.87),(1 666.11 ms,7.63%,3.46)和(1 260.34 ms,6.38%,3.74)。结论 3种改进的目标选择技术呈现出了比直接触摸法更优秀的目标选择能力。     

基于摄像机标定技术设计的3D输入设备

介绍一种基于摄像机标定技术的3D输入设备的原理,采用微软研究院的张正友提出基于移动平面模板的摄像机标定方法,分析计算机视觉函数库OpenCV中的摄像机模型;对比棋盘上的角点和其图像的对应点,利用直接线性变换以及最小二乘法来求解摄像机的内参、畸形系数;通过摄像机实时采集不同位姿的棋盘图片,运用空间解析几何,计算出棋盘的位姿.实验结果表明,把棋盘的位姿转化成3D信号输入,可用于虚拟现实系统的3D交互设备,并具有良好的稳定性和准确性,可满足3D输入设备的需求.     

移动手持触摸设备中提高目标选择精度的研究

在直接触摸设备上,利用手指直接点击/选择小目标通常会产生误操作。针对此问题,实证地研究了用户使用不同目标选择技术在移动触摸设备上的性能表现。除了传统的直接点击选择目标技术之外,本研究还设计和实现了三种改进的目标选择技术,分别为：平移放大技术、倾斜技术和吸引技术,而且通过设计实验程序并采集实验数据,评价、对比了四种目标选择技术的性能。研究结果表明三种改进的目标选择技术都比直接点击技术效果好。详细的数据分析进一步阐述了不同目标选择技术的特点和差异。基于实验结果,本研究阐明了改进的目标选择技术在实际应用中的适用场景,以及在用户界面设计中的指导意义。     

面向惯用手的笔+触控输入

针对单手情况下笔的输入能力有限、触控输入精确度低且存在手指遮挡等问题,为了发挥笔和触控各自的优势,提出面向惯用手的笔+触控输入技术.首先设计和展开目标装入实验,分析了笔和触控输入的性能特点.然后结合绘图场景,提出顺序法、交叠法和并行法3种面向惯用手的笔+触控混合输入技术,以及用作对比的按钮法参考技术,并通过实验考察了4种输入技术的性能,结果表明,笔在小目标操作的精度和速度上优于触控;相比于按钮法,交叠法在操作时间和轨迹偏移量方面分别减少了15.9%和0.2%;并行法在时间和偏移量方面分别增加了25.6%和40.5%;顺序法在操作时间方面增加了11.2%,但是在偏移量方面减少了12.8%.最后给出了各种不同混合输入技术的应用场景,对面向惯用手的笔+触控交互和用户界面设计具有指导意义.     

体电流法分析矩型芯倾斜光纤光栅的辐射场

利用VCM法(volume current method)分析了矩形芯倾斜光纤光栅的辐射场特性.数值仿真了辐射场的二维空间分布,分析了矩形芯倾斜光纤光栅对不同偏振输入光的偏振敏感性.仿真结果表明,矩形芯倾斜光纤光栅对y偏振光的辐射效率比x偏振光的高;光栅的倾斜角越小,对不同偏振输入光的偏振敏感性也越小.X偏振光和Y偏振光的峰值辐射功率差在光栅倾角为3°时为1.8%,当光栅倾角增大到15°时达到16%.而在倾斜角小于7°的情况下,X和Y偏振光的辐射功率峰值差小于5%.     

产品

ATEN CS661笔电聪明连编/鞠道霖这款看似简单的USB连线是ATEN公司最新推出的产品,支持KVM功能,可利用这样一个简单的设备同时实现对两台电脑的操作——用户无需在两台电脑的输入设备(键盘,鼠标等)上来回切换,而只需使用一台电脑即可控制第二台电脑。CS661笔电聪明连中内置了驱动及自动运行软件,无需额     

计算机输入新技术—屏幕触摸输入

美国Fluke公司MCS2452智能控制机CRT显示器上配有触摸敏成涂层,因而屏幕可以当作输入设备用,不用键盘也可完成人机对话功能。输入时只需用手指触摸一下屏幕上相应的位置即可完成有效输入。本文概述了屏幕显示系统的功能、操作及应用。     

Touch a screen or turn a knob: choosing the best device for the job

Input devices enable users to interact with systems. In two experiments, we assessed whether and how task demands and user age influenced task performance for a direct input device (touch screen) and an indirect input device (rotary encoder). In Experiment 1, 40 younger (18-28 years) and 40 middle-aged to older adults (51-65 years) performed tasks using controls such as sliders, up/down buttons, list boxes, and text boxes while using a system. The optimal input device to facilitate performance was dependent on the task being performed and the age of the user. In Experiment 2, touch screen use was assessed for 20 younger (19-23 years) and 20 older adults (51-70 years). Task demands were manipulated through button size, movement distance, direction, and type of movement. Performance was moderated by the age of the user and by task demands. Actual or potential applications of this research include guidance for the optimal selection of input devices for different user populations and task characteristics.     

Light pen use and practice minimize age and hand performance differences in pointing tasks

We contrasted performance with mouse and light pen input devices for younger, middle-aged, and older adults (N = 72) who were experienced mouse users. Participants used both preferred and nonpreferred hands to perform a menu target selection task. The light pen minimized age differences in performance relative to the mouse. Older adults were more lateralized on a handedness test than young adults and were less efficient using their nonpreferred hand. With practice, older adults improved their response time more than other age groups did. The mouse was rated as more acceptable and easier to use than the light pen across trials, despite the performance advantage of the light pen for all age groups. Usability ratings correlated moderately with performance. A benefit-cost analysis indicated that the more efficient light pen might cover its greater initial cost within 11 months for an older adult and within 23 months for a younger adult. Actual or potential applications of this research include advising older adults to persist with practice for new input devices, advising those who must switch to their non-preferred hand to select a direct positioning device, and providing a methodology for determining the potential payback interval when switching to a faster, though more expensive, input device.     

Effectiveness of hand- and foot-operated secondary input devices for word-processing tasks before and after training

Previous research has shown that, without practice, users are slower using the foot than the hand to control input devices. This study compared the performance (before and after practice) of users operating a foot-controlled secondary input device (foot mouse) with the performance of users operating a hand-controlled secondary input device (hand trackball) to complete four word-processing tasks requiring various amounts of keyboard and secondary input device use. Before practice, hand trackball performance was better on all tasks. After practice, hand trackball performance was better on all tasks except the task requiring the greatest amount of keyboard use, for which there was no significant difference between devices. For all tasks, practice improved performance with the foot mouse but not with the hand trackball. These findings suggest that, with enough practice, it may be efficient for users to use a foot input device for tasks that also require keyboard input.     

Comparison of Gaze Cursor Input Methods for Virtual Reality Devices

Virtual reality (VR) devices have recently become popular; however, research on input methods for VR devices is lacking. The main input methods of current commercial devices can be classified into two categories: manual selection using a controller and gaze selection. This study aims to derive the optimal input method and timing for VR devices by analyzing the performance of these input methods. A study is conducted in which participants wear a VR headset and select an activated input button from a 3 × 3 array on a VR device with two button sizes and two input methods. The manual selection method exhibits a shorter task completion time but a greater error number compared to the gaze selection method. For the gaze selection method, the task completion time and target search time were shortest when the gaze timing was 1 s. Further, the button size was determined to be statistically significant only when the manual selection method was used. The results of this study can be used as a reference in future VR user experience and product design.     

Input devices for web browsing: age and hand effects

The work reported in this paper examined performance on a mixed pointing and data entry task using direct and indirect positioning devices for younger, middle-aged, and older adults (n=72) who were experienced mouse users. Participants used both preferred and non-preferred hands to perform an item selection and text entry task simulating a typical web page interaction. Older adults performed more slowly than middle-aged adults who in turn performed more slowly than young adults. Performance efficiency was superior with the mouse for older adults only on the first two trial blocks. Thereafter mouse and light pen yielded equivalent performance. For other age groups, mouse and light pen were equivalent at all points of practice. Contrary to prior research revealing superior performance with a light pen for pure pointing tasks, these results suggest that older adults may initially perform worse with a light pen than a mouse for mixed tasks.     

To twist or poke? A method for identifying usability issues with the rotary controller and touch screen for control of in-vehicle information systems

In-vehicle information systems (IVIS) can be controlled by the user via direct or indirect input devices. In order to develop the next generation of usable IVIS, designers need to be able to evaluate and understand the usability issues associated with these two input types. The aim of this study was to investigate the effectiveness of a set of empirical usability evaluation methods for identifying important usability issues and distinguishing between the IVIS input devices. A number of usability issues were identified and their causal factors have been explored. These were related to the input type, the structure of the menu/tasks and hardware issues. In particular, the translation between inputs and on-screen actions and a lack of visual feedback for menu navigation resulted in lower levels of usability for the indirect device. This information will be useful in informing the design of new IVIS, with improved usability.

Statement of Relevance: This paper examines the use of empirical methods for distinguishing between direct and indirect IVIS input devices and identifying usability issues. Results have shown that the characteristics of indirect input devices produce more serious usability issues, compared with direct devices and can have a negative effect on the driver–vehicle interaction.     

Using non-keyboard input devices: interviews with users in the workplace

A study of 45 non-keyboard input device (NKID) users was undertaken at nine organisations to investigate the extent, pattern and method of NKID usage, workstation configurations, postures adopted and musculoskeletal symptoms. A number of methods were used: work activity diaries, interviews, observations and postural assessments. A range of NKID were seen including the mouse, touchscreen, joystick, trackball, and tablet and pen; however, the mouse was the most commonly used device. Use of an input device varied from 2% to 100% of the working day. Workers undertook common tasks using a variety of methods (e.g. pull down menus, icons, device buttons). Users reported problems associated with the use of some devices, e.g. poor maintenance, lack of device responsiveness. Musculoskeletal pain and discomfort (e.g. stiffness and discomfort in the hands and wrist) was reported by 45% (n=19) of mouse users and 16% (n=5) of other NKID users. Workstation configurations varied and in some cases constrained the position of the input device, resulting in users having to work with the device at some distance away from the body. Despite the existence of regulations and guidance, this paper indicates that there are still many problems related to NKID use at computer workstations.

Relevance to industry

The reliance of many software applications on NKID (e.g. mouse, trackball, touchpad, joystick, touchscreen) necessitates the investigation of their use in the workplace. Whilst the performance aspects of NKID (e.g. speed) have been well researched, the possible implications for user health have received little attention in the UK.     

A Dynamic Gesture Language and Graphical Feedback for Interaction in a 3D User Interface

In user interfaces of modern systems, users get the impression of directly interacting with application objects. In 3D based user interfaces, novel input devices, like hand and force input devices, are being introduced. They aim at providing natural ways of interaction. The use of a hand input device allows the recognition of static poses and dynamic gestures performed by a user's hand. This paper describes the use of a hand input device for interacting with a 3D graphical application. A dynamic gesture language, which allows users to teach some hand gestures, is presented. Furthermore, a user interface integrating the recognition of these gestures and providing feedback for them, is introduced. Particular attention has been spent on implementing a tool for easy specification of dynamic gestures, and on strategies for providing graphical feedback to users' interactions. To demonstrate that the introduced 3D user interface features, and the way the system presents graphical feedback, are not restricted to a hand input device, a force input device has also been integrated into the user interface.