振動環境下指標輸入設備比較與 Fitts' Law Model之建立

Fitts' Law Model and Comparison of Pointing Devices in Vibration Environment

劉祺諾(Chi-No Liu)

指導教授 ： 林久翔

中原大學/工學院/工業工程研究所/博士(2008年)

https://doi.org/10.6840/CYCU.2008.00046

摘要

本研究使用史都華平臺產生六自由度(6 degree of freedom)之振動環境，將電腦工作站與10位26~31歲之受測者置於振動環境下，操作滑鼠、軌跡球及觸控螢幕等不同之指標性輸入設備，進行Fitts' law task，探討各輸入裝置之移動時間、錯誤率、點擊落點位置的分佈等特性，並進一步探討各輸入設備於振動環境下合理之目標大小設計、生產率及Fitts' law model，分析出適合於振動環境使用之輸入裝置。
結果得知，隨著振動環境的增加，造成輸入設備的生產率皆降低，滑鼠的Fitts' law model為MT=389+123log2D+212log21/W +578av,comfort，其特性為隨著振動環境之增加，點擊落點位置之分佈範圍變大及點擊錯誤率增加的現象，因點擊落點位置較觸控螢幕及軌跡球更接近目標中心且分佈較為集中，有效目標寬度增加的有限，雖然移動時間較觸控螢幕略長，但振動環境下生產率最佳；觸控螢幕的Fitts' law model為MT=335+119log2D+275log21/W +427av,comfort+42sinθ，其特性為移動時間較短，靜態環境下生產率最佳，隨著移動角度的增加，移動時間跟著增加、隨著振動環境的增加，點擊落點位置離目標中心最遠且分佈範圍的增加較滑鼠及軌跡球更為明顯，因此點擊錯誤率明顯的增加，造成有效目標也明顯增加，振動環境下生產率低於滑鼠，顯示出觸控螢幕較無法抵抗振動之環境；軌跡球的Fitts' law model為MT=1031+44D+611[(1/W)-1]-147av,comfort，其特性為隨著振動環境的增加，點擊錯誤率較滑鼠及軌跡球為低、隨著振動環境的增加，點擊落點位置之分佈範圍增加不如滑鼠及軌跡球明顯，造成有效目標寬度的增加較不明顯，顯示軌跡球較能抵抗振動之環境，但因受到移動時間較長的影響，造成不論何種環境下生產率皆最差。

關鍵字

throughput ； 振動環境 ； 輸入裝置 ； Fitts' law task

並列摘要

In this study, the Steward platform was used to produce a vibration environment of 6 degrees of freedom. The workstation and 10 subjects 26~31 years of age were in the vibration environment to operate different pointing devices including a touch screen, a mouse, and a track ball. The subjects were requested to perform the Fitts' law task for identifying the characteristics of movement time, error rate, and end-point variation. The target size, throughput and Fitts' law model were analyzed for each pointing device in this study to find out the pointing devices that were most suitable for operation in the vibration environment.
As the results showed, the throughput of each pointing device decreased with increase of vibration. The Fitts' law model of the mouse was MT=389+123log2D+212log21/W +578av,comfort. The distribution of the end points and the clicking error rate increased with the increase of the vibration. The end points were closer to the target center and distributed more centrally than the touch screen and track ball. The effective target width increased to a limited extent. Though the movement time is longer than the touch screen, the throughput is higher in the vibration environment. The Fitts' law model of the touch screen is Fitts' law model was MT=335+119log2D+275log21/W +427av,comfort+42sinθ. It had a shorter movement time and a better throughput in a static environment. The movement time increased with the increase of the movement angle and vibration. The position of the end points was farthest away from the target center and their distribution increased more significantly than the mouse and trackball. As a result, both the clicking error rate and the effective target width increased to a significant extent and, thus, the throughput was lower than the mouse, indicating that the touch screen was less capable of resisting the vibration environment. The Fitts' law model of the track ball was MT=1031+44D+611[(1/W)-1]-147av,comfort. With increase of the vibration, the clicking error rate decreased to be lower than the clicking error rate of the mouse and the touch screen. Though the distribution of the end points increased with the increase of the vibration, it did not increase as significantly as the mouse and touch screen, resulting in an insignificant increase of the effective target width. It indicates that the track ball was more capable of resisting the vibration environment but had the worse throughput due to long movement time.

並列關鍵字

vibration environment ； Fitts' law task ； throughput ； pointing device

參考文獻

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