Design and evaluation of dynamic text-editing methods using foot pedals

The objective of this study was to design and evaluate new dynamic text-editingmethods (chatting, instant messenger) using a foot pedal control. A first experiment was to assess whether the foot-based method enhanced editing performance compared to conventional mouse use and to identify which type of foot control is most convenient for users. Five prototype methods including four new methods (two pedals or one pedal, 0 order or 1st order control), and one mouse method were developed and tested by performing a task requiring changing text sizes, dynamically. Results revealedmethods involving 1st order pedal control to be comparable to the conventional method in task completion time, accuracy and subjective workload. Among the four foot control prototypes, two pedalswith 1st order controlwas superior to inperformance. A second experiment was conducted to test another prototype foot-based method for controlling font face, size, and color through feature selection with the left pedal and level selection with the right pedal. Textediting performancewas compared to conventionalmouse-based editing. Results showed the foot pedals to degrade performance in terms of task completion time. However, the prototype interface has the advantage of making certain system functionality accessible to special populations thatmight not otherwise be able to use dynamic text-editing applications. Subjective comments demonstrated the foot pedal methods to be considered useful, time efficient and to reduce workload. It was observed that skilled users might perceive some relief from cumbersome mouse handling behaviors during typing. Although the foot pedal control was not revealed to significantly increase text-editing performance over conventional mousing, the use of foot pedals may be considered in computing operations, including dynamic text-editing tasks, as an alternative or additional input method, particularly for special populations. Relevance to industry: The development and evaluation of foot control interactionmethods for text editingmay provide useful insight for human-computer system designers considering the use of additional input devices or ways to support user expressions of emotion in text. The foot control approach may also be useful in interaction design for special populations (with functional limitations of the upper limbs) in terms of accessibility. 2008 Elsevier Ltd. All rights reserved.