TapSense is a project that enhances touchscreen technology by allowing surfaces to identify the type of object being used for input. Researchers Chris Harrison, Julia Schwarz and Scott E. Hudson, at the Human-Computer Interaction Institute and Heinz College Center for the Future of Work, Carnegie Mellon University have found a means that can identify different parts of the anatomy of a human finger including the tip, pad, nail and knuckle. It utilizes sounds resulting from a finger's impact. That's not all; the same prototype can also sense different tools including foam, multiple pens types, and brushes. The system could sense who was using which pen, allowing for collaborative drawing.
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