Designing robust multimodal systems for diverse users and environments.

Multimodal interfaces are being developed that permit our highly skilled and coordinated communicative behavior to control system interactions in a more transparent and flexible interface experience than ever before. The presence of modality choice per se is an important feature and design issue for multimodal interfaces. As applications become more complex, a single modality does not permit varied users to interact effectively across different tasks and environments (Oviatt et al., 2000). While individual input modalities are well suited in some situations, they may be less ideal or even inappropriate in others. However, a flexible multimodal interface offers people the freedom to use a combination of modalities, or to switch to a better-suited modality, depending on the specifics of their abilities and preference, the task at hand, or the usage conditions.