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.

Objective Fat finger, target occlusion, and physical fatigue often reduce the precision of touch input, and these factors might degrade mobile handheld touch conditions. This study aims to identify strategies by which to improve the accessibility of small target selection and touch input precision. Moreover, this work empirically investigates and compares the performances of these strategies. Method The tilt and movement acceleration detection function of mobile touch devices is used to explore the performance, characteristics, and suitable usage of four kinds of target selection techniques, namely, direct touch, shift & zoom, tilt, and attraction. Direct touch is a baseline technique used only for comparison. The other three are techniques proposed to improve target selection. Result The subjects used the longest time to select the target and to produce brief finger movement displacement. However, few selection errors were committed with the tilt technique. Shift & zoom was ranked as the most favored technique according to user evaluations. Attraction technique exhibited least selection errors and shortest selection time. The subjects committed the highest number of selection errors with direct touch technique. The targets located in the northwest or southwest corners of the screen are likely to be successfully selected. The following are the average selection time, error rate, and subjective evaluation of the four target selection techniques: 86.06 ms, 62.28%, and 1.95; 1 327.99 ms, 6.93%, and 3.87; 1 666.11 ms, 7.63%, and 3.46; and 1 260.34 ms, 6.38%, and 3.74. Conclusion The three improved target selection techniques outperform direct touch. Each method presents individual characteristics and discrepancies. This study presents guidelines for touch interaction design on mobile devices in target selection.