Abstract:
Fitt’s Law is commonly used to model motor performance in computer pointing devices. Using Labview software, this research developed a series of omni-directional pointing task to collect, characterize and evaluate computer mouse operation based on Fitts’ Law. Using a repeated measures design fourteen children between the ages of 5-8 and their same gender biological parent (28 subjects total) performed a series of small medium and large pointing tasks, with both a standard and a child-proportional sized mouse. Results demonstrated that adults performed better than children on all three tasks across the performance parameters measured. Interestingly, both adults and children were faster and made fewer errors wit the small mouse. This indicated that a small mouse could be shared in a home environment without any compromise in performance to adults or children. During the performance of the small tasks, subjects were more proficient when using the small mouse likely due to being able to use fine finger movements to manipulate the mouse within the palm of the hand. There were significant differences in mouse button click time between adults and children (children 150 + 2ms VS. adults 103 + 1ms; p=0.002) and between mice (standard mouse 119 + 2ms VS. small mouse 136 + 2ms; p<0.0001). Based on measured mouse button click times and anthropometric differences between children and adults, not only should mice be proportional in size, but the button activation forces should also be proportional to the finger mass and strength. Systematic methods for characterizing and measuring pointing device performance was established.