Tittiranonda P, Rempel D, Armstrong T, Burastero S
Interdisciplinary Ergonomics Program, Lawrence Livermore National Laboratory, University of California 94550, USA.
Am Ind Hyg Assoc J. 1999 May-Jun;60(3):340-8. doi: 10.1080/00028899908984451.
This study presents an evaluation of an adjustable keyboard based on subjective preference and wrist joint motion during typing. Thirty-five computer users used the adjustable split design keyboard for 7-14 days during their usual work and were instructed to adjust the keyboard to the opening angle they preferred. At the end of this period, three-dimensional motion analysis was performed to compare the distribution of wrist joint angles while subjects typed on a conventional keyboard and the adjustable keyboard adjusted to the subject's preferred angle. The mean preferred opening angle was 14 degrees +/- 10. The mean ulnar deviation of the subjects who selected the opening angles between 21 and 28 degrees (n = 12) decreased from 18 degrees +/- 5 on the flat to 14 degrees +/- 5 on the adjustable (p < 0.05), while those who selected 0 to 10 degrees (n = 6) and 11 to 20 degrees (n = 17) split angles showed no significant differences in ulnar deviation. Mean wrist extension on the adjustable keyboard was 17 degrees +/- 5 and was significantly less than the 24 degrees +/- 5 observed on the conventional keyboard and most likely due to the presence of palm support. On average, subjects reported that the adjustable keyboard was more comfortable (0.5 +/- 0.5) (worse = -1, same = 0, better, = 1) in comparison with the conventional keyboard.
本研究基于打字过程中的主观偏好和腕关节运动对一款可调节键盘进行了评估。35名计算机用户在日常工作中使用这款可调节分体式设计键盘7至14天，并被要求将键盘调节至他们喜欢的打开角度。在这段时间结束时，进行了三维运动分析，以比较受试者在传统键盘上打字以及在调节至受试者偏好角度的可调节键盘上打字时腕关节角度的分布情况。平均偏好打开角度为14度±10度。选择打开角度在21度至28度之间的受试者（n = 12）的平均尺骨偏斜度从平面时的18度±5度降至可调节键盘上的14度±5度（p < 0.05），而选择0度至10度（n = 6）和11度至20度（n = 17）分体角度的受试者在尺骨偏斜度上没有显著差异。可调节键盘上的平均腕关节伸展角度为17度±5度，明显小于在传统键盘上观察到的24度±5度，这很可能是由于有手掌支撑。平均而言，与传统键盘相比，受试者报告称可调节键盘更舒适（0.5±0.5）（较差 = -1，相同 = 0，较好 = 1）。
