**3. Experimental Investigation**

We have adopted a triangulation based method [33] by covering multiple approaches to address a research question, which offers an appropriate and reliable assessment. Based on our preliminary study for tactile-color cross-modular association, an improved solution has been proposed in the preceding section. The tactile perception large-scale prototype was developed which can produce dynamic results based on reference color. User experiments for design, methodology, and cross-modular association have been performed to evaluate usability and workload assessment, while qualitative feedback is also recorded for the proposed method and exploratory procedure.
