To those who might think it a tad frivolous, this is serious hardware and software, potentially with lifesaving capabilities. For example, Penn engineers have previously programmed similar robots to dart into a building and capture images, creating a virtual 3-D map that could be beamed to emergency personnel.
The flying 'bots have even been used in lab-scale construction projects, assembling a simple scaffold of girders and beams. That one caught the attention of Comedy Central's Stephen Colbert, who proclaimed ominously that the machines would "enslave" the human race.
Playing musical instruments, on the other hand, was more just for demonstration purposes. But what a sense of tempo.
It all began last week when Vijay Kumar, a faculty member at Penn's General Robotics, Automation, Sensing and Perception (GRASP) Lab, learned that he was a late addition to the schedule at the TED conference.
The conference, held each year in California, has become a magnet for technophiles and creative thinkers, this year drawing speakers from the worlds of physics, neuroscience, climatology, and music, among others.
Kumar asked lab members Daniel Mellinger and Alex Kushleyev to come up with something cool to accompany his talk, and they tossed around the idea of having the robots play music.
The team enlisted the help of Kurtis Sensenig, a video producer at Penn, and the group then narrowed the choices down to the themes from Star Wars, Rocky, and the Bond movies. The spy won.
"It has a pretty simple note structure and is pretty repetitive," Sensenig said.
In addition to the standard garage-band instruments of keyboard, drums, and electric guitar, the group created its own: the couch guitar.
This was made from the frame of an old couch, strung with guitar strings placed in order of the melody so the robots could simply glide in one direction to play the song rather than going back and forth.
"It was actually sitting in the lab for over six months," Kushleyev said of the wooden frame. "I was about to get rid of it."
Then came a last-minute marathon of programming, rewiring, and filming over the weekend - more than 40 hours all told, with one 20-hour stretch from 10 a.m. Saturday until 6 a.m. Sunday.
The robots played the keyboard by alighting on stiff pieces of cardboard attached to the keys. The engineers rewired the keyboard to space out the necessary notes, so that the robot musicians would not bump into each other.
The couch guitar was played by having robots drag a rod across the strings. Another robot moved up and down, repeatedly dropping a hex nut on the cymbals.
Previously, engineers at Penn had customized quadrotors that were built by a manufacturer. Mellinger and Kushleyev now make their own, through a company they started called KMel Robotics. They are no longer students at Penn, but they retain visiting appointments with the lab.
Alas, their mechanical musicians are not available to play gigs.
But if the sound of the couch guitar catches on, can bar mitzvahs be far behind?
Watch a swarm of Penn's flying robots play and dance to the James Bond theme at
Contact Tom Avril at 215-854-2430 or firstname.lastname@example.org.