www.servomagazine.com/index.php?/magazine/article/october2010_GeerHead
GEERHEAD
During a recent semester, students in the Conducting Robots course constructed three robots. Chris Ault,
associate professor of Interactive Multimedia; Dr. Teresa
Nakra, associate professor of Music; Dr. Andrea Salgian,
assistant professor of Computer Science; and Dr. Jennifer
Wang, associate professor of Mechanical Engineering
taught the class. Seventeen students took the course and
made up three teams of roboticists.
Requirements included that the robots use both
visualization and mechanical motion to communicate cues
and instructions on tempo, dynamics, and articulation to
the orchestra.
There has been little attempt by roboticists to date to
create robots to conduct orchestras. A couple exceptions
were Honda’s ASIMO robot conducting the Detroit
Symphony in 2008, and Honda’s QRIO that conducted the
Tokyo Philharmonic Orchestra for 90 seconds in March ‘04.
However, the robot’s pre-coded activity did not include true
interaction with the musicians in the orchestra.
The TCNJ students were provided with the input from
MIDI files. This and visual analysis helped to give the robots
more human-like gestures. The robots were able to convey
more information than ASIMO.
ACRE Robot
The ACRE or Automated Conducting Robot Experience
robot is a human size robot. The team built it with an
upper frame and a lower frame to simulate the human
torso and legs, respectively. The upper frame consists of
three plates used to accommodate a laptop, a monitor
(to simulate the conductor's face), and other necessary
equipment. The arms were connected to the top plate, or
shoulder plate. The team made the frame of aluminum
6061 for its strength, rigidity, and ease of use.
Since the robot's right arm keeps the tempo, its
movement is on a fixed path that can be achieved with only
three degrees of freedom: two in the shoulder joint and
one in the elbow joint. There is a gripper at the end of the
right arm for a hand.
The left arm has two degrees of freedom (more can be
added) and is used to indicate cueing and volume control
to the orchestra.
Each arm motor is a Hitec HSR-5990TG servo motor.
The team selected this motor because it provided enough
torque to enable the necessary arm capabilities given the
arm’s weight and other factors. The gripper is a Lynxmotion
Little Grip servo motor.
An Arduino Duemilanove was used for the arm’s motor
controller. The team chose it for its open source platform
which made it easy for team members to select and write
code for the necessary functions. The Arduino was
programmed in Processing — a programming language that
is an extension of the Java language.
The lower body is a rectangular frame design with four
ACRE
At the recent performance of the TCNJ robot
builds, the ACRE robot led a portion of music from West
Side Story (written by Leonard Bernstein). The goal of
this robotic project is to imbue the necessary traits of a
human conductor so that it leads an orchestra through
a given piece of music. The robot’s aesthetics bridge the
gap between the human and robotic worlds, combining
human and robotic features, according to the
roboticists at TCNJ.
The robot proffers visible, physical cues from which
the orchestra takes its lead. According to the students,
this robot’s functions and communication modes
include:
- A right arm that conducts the beat pattern.
Resources
The College of New Jersey
www.tcnj.edu
Videos of the robotic conductors
http://creativeit.immtcnj.com/video
Grant aids Conducting Robots Course
www.tcnj.edu/~pa/news/2009/creativeitgrant.htm
SERVO 10.2010 11