Servo - September 2010

GEERHEAD

translating the notes into instrumentation by the robot’s hands.

The team would have to use an inexpensive web cam and a common laptop instead of the costly, high frame rate camera and high speed controller device used by NI. The students were concerned the camera might not be fast enough to pick up all the notes and that the laptop might not be fast enough to process the vision task and control the robot’s fingers (guitar actuators).

Fortunately, Team Titanium was able to use NI’s LabVIEW industrial control software which helped the team in producing their FIRST competition robots. The software includes video and vision tools and libraries, but would that be enough to create sufficient programming to recognize all the notes and outgoing signals for each note?

The web camera mounted in front of the TV where the notes are displayed.

A Glimmer of Hope

off: a Guitar Hero playing machine,” says Jeff Spatz, head coach of the high school Team Titanium.

The NI system used an industrial machine vision camera, a high speed controller, and a complex pneumatics system to play the plastic guitar as part of the famous video game. The NI robot used the camera to read the notes rolling off the TV screen so the robot could play them — and play them quite well.

Building a robot better than that of NI posed several problems. Cost was a factor, since the high school robotics team operated on a very limited budget. During the first stage of development, the team focused on duplicating the robot’s real-time vision task: seeing, transmitting, and Within a few short hours of tinkering, the team’s software writer had a program running. The web cam was watching the TV screen, the game was running, and the program was flashing lights on the LabVIEW interface in tandem with the notes on the screen. “We did not know if the results were good enough to play the game well, but it was clearly good enough that we knew the vision task was within reach,” remarked Spatz.