Once students have learned the basics about using a standard analog straight edge, this rolling digital ruler could certainly aid in accelerating their mathematics practices. Lee Hwa-yeon and Park Chan-ju have developed an idea for a compact measuring tool that is portable and computerized for the convenience of youngsters and working adults alike.
With a length less than that of an A4 sheet of paper, the Smart Rolling Ruler would surprisingly be able to measure infinite distances. A system of conveyor-belt-like wheels enables the gadget to crawl along consistently, displaying a live virtual scroll of passing unit markings. This touchscreen keeps reading ranges and can record your results. The rolling digital ruler can then be used as a calculator with a built-in unit converter.