C-Sak: Chinese Scanning Ambiguous Keyboard For Parkinson'S Disease Patients

Text based communication via computing devices has become an important aspect of human life. Keyboard is a standard device to input text and requires many key presses to enter a single pinyin based Chinese character. Patients with motor impairment such as those suffering from Parkinson's disease (PD) need specialized text input systems. Chinese being a non-alphabetic language is based on a large number of characters, therefore designing an efficient and error free Chinese text entry system with reduced number of keys is quite challenging. This paper presents a novel Chinese Scanning Ambiguous Keyboard (C-SAK) model for Pinyin based Chinese text entry system which requires a minimum input signal, one key, for the input interaction. Based on the analysis of Pinyin, an optimized pinyin model is implemented. The resulting system is a combination of high efficiency, accuracy, and easy learn-ability into C-SAK. The model being simple and efficient maintains a balance between efficiency and ambiguity and minimizes physical fatigue for motor impaired patients. Experiments using C-SAK conducted with native Chinese speakers suffering from Parkinson's disease show a 1.5 times faster Mandarin input rate and 20% less error rate as compared to traditional QWERTY application. Access to an alternate Chinese input system is socially impactful as it allows millions of PD patients and elders with motor impairment to input text effectively.