R2-D2’s broken beamformer: A galactically consequential homework exercise

Abstract

Identify the Imperial spy, assist the Rebellion, and save a galaxy far, far away! In “Acoustical Measurement Methods,” a Brigham Young University physics course typically taken by seniors and new graduate students, the semester’s culminating topic is beamforming. Students write their own delay-and-sum (DAS) beamformers for a uniform line array and test them experimentally by finding the direction of a loudspeaker. The topic of their technical memorandum, however, is a homework-style exercise in which they use their validated DAS codes to help R2-D2 locate the Imperial spy in the Mos Eisley cantina. With the spy’s inquiry about the Rebel base masked by a cacophony of sounds coming from different directions, and with its real-time processor on the fritz, the dependable droid needs help processing its phased-array signals to separate the sources and locate the spy. Though this exercise doesn’t follow the Star Wars® canon in the least and certain dimensional constraints are temporarily cast aside in the DAS problem creation, students do not seem to care. They engage deeply in the problem and generally produce their best-written technical memorandum of the semester in pursuit of intergalactic (though still academic) valor and fame. “Help me, [acoustics student], you're my only hope!”