Study On Adaptive Design For The Key Size Of Soft Keyboard On Large Touch Screen

As an input device, soft keyboard plays a very important role in thehuman-machine interaction. How to improve the usability of soft keyboard based onthe individual differences, has become the focus of the researchers, The present studyinvestigated how to adopted the adaptive technology to design the size of softkeyboard on large touch screen in order to get better usability.This study explored the relationship between the key size and the inputefficiency through an experiment. Based on the results, we designed a soft keyboardwhose key size can be adaptive, and compared it with the fixed-size and custom-sizesoft keyboard, from the aspects of user satisfaction and performance of input.The study is divided into three parts:The first part of the study is include Expt.1. It explored the effect of key size onperformance of input, in order to get the data to design the soft keyboard withadaptive key size.The second part of the study is include Expt.2and Expt.3. And this part is toevaluate the usability of the adaptive keyboard, by comparing it with the fixed-sizeand custom-size soft keyboard, with the indexes of performance and user satisfaction.The second part of the study is include Expt.4and Expt.5. And this part of studytestified whether the adaptive soft keyboard was more advantageous than the othertwo types of soft keyboards in the time-limited situation, using the same methods withExpt.2.Results show that:(1) Compared with the fixed-size soft keyboard, the adaptive keyboard is notbetter in both the performance of input and user satisfaction. Compared with thecustom-size keyboard, the custom-size keyboard is better in the user satisfaction, butnot in the performance.(2) There is individual effect when comparing adaptive soft keyboard and the fixed-size soft keyboard. The users showed advantage in using the adaptive keyboard,whose final adaptive key sizes are different with the fixed key size. Otherwise there’sno significant difference in the performance between the adaptive and custom-sizekeyboards.(3) In the time-limited situation, the adaptive keyboard is better than thefixed-size keyboard. But there is no difference between adaptive keyboard andcustom-size keyboard.The present study explored the adaptive design for the key size of soft keyboardon large touch screen. The findings of the study have important theoretical andpractical significance for better personalized design and improvement of inputperformance of soft keyboard.