“Watching the original ‘Star Wars’ movie as a mathematically inclined 11-year-old, Helen Greiner dreamed of someday creating a robot like the heroic R2-D2. After enduring plenty of lean years chasing that elusive vision as a co-founder of iRobot Corp., Greiner can now boast a product that whirs and chirps much like the character she to this day calls her ‘personal hero.’” The Globe profiles iRobot co-founder Helen Greiner, whose company boasts Roomba, Scooba, and the Packbot, a military minesweeper that, if Greiner has her druthers, won’t be breaking Asimov’s First Law anytime soon.