Servo - October 2008

by David Geer

Contact the author at geercom@alltel.net

Robot250 Features BigBots

Robotic Artwork that Interacts and Responds

Robot250 is a city-wide extravaganza of large scale interactive robot art projects, workshops,

festivities, events, and film held July 11-27 in Pittsburgh, PA. Sponsored by Carnegie Mellon

University, the University of Pittsburgh, and a number of local community groups like the

Heinz Endowments, the program features BigBots interactive robot displays with artistic themes.

You’re No. 1 ... Really!

Ian Ingram, BigBot curator and creator of the “You’re No. 1” robotic foam hand and finger interpretation atop the Andy Warhol Museum spoke about the BigBots, beginning with his own work (at my request).

The nearly seven yards of Pittsburgh black and yellow foam hand and index finger spread the love by reaching out to visitors to say they were no. 1. The hand moved, positioned itself, and pointed at various visitor outposts miles away and throughout the city using dual-axis hydraulics. One axis was a hydraulic motor and one was a hydraulic actuator.

The hydraulics gave the hand two degrees of freedom (DOF) of

movement. The first DOF held the hand straight up and twisted it around while the second moved it downward to point it at the outposts or to wave at people. All the action was automated by a small microcontroller, though the original plan was to have kiosks at the outposts with remote triggers to activate the hand and point it in the specific direction of the kiosk that triggered the response.

The robotic hand made use of sensing and a limiting switch — a gross encoder — which told the robot when to stop and start its movements. The hand was fitted with a camera that lined up in varying positions equal to a straight line to the different outposts.

The PIC microcontroller was

brought to life using software created in C programming. The software looks for limit switch hits, making plans for movement between where the hand is and where it needs to go to perform the pointing and waving, according to Ingram.

The robot uses a motor to pump fluid to create pressure to activate and manipulate the hydraulics. The hydraulic valves use solenoids and are pushed by external signals from the microcontroller. The structure of the hand is steel weldments with polyurethane foam similar to the hands that people take to sports games.

The “You’re No. 1” BigBots robotic installation by Ian Ingram is a 20-foot tall robotic black and yellow foam hand and finger like the ones worn by fans of Pittsburgh’s most famous sports team. The maneuvering hydraulic hand appeared on the roof of the Andy Warhol Museum in Pittsburgh as part of the Robot250 Festival, which ran July 11-27, 2008. Ingram, BigBot curator, senior research associate, and artist-in-residence at Carnegie Mellon University, built the big hand, which pointed at passers-by around the city.

Semi-autonomous Percussive Devices Communicate Like Crickets

The Crickets installation uses a number of interconnected robotic sculptures to imitate the action and reaction of group communication among packs of animals such as dogs or insects. The robots are equipped with wooden knockers controlled by solenoids to tap out their noises.