Flying over obstacles that life can hurl your way is an enviable ability of superheroes, extra-terrestrials, and now—IIT's rolling and flying robot.
Assistant Professor Matthew Spenko and doctoral student Arash Kalantari of IIT Armour College of Engineering developed the 'bot, known as the hybrid terrestrial and aerial quadrotor (HyTAQ), as part of a United States Navy Office of Naval Research project. The goal of the project was to create a micro aerial vehicle capable of perching and moving on vertical surfaces composed of various types of materials, such as drywall, brick, or glass. The HyTAQ's capabilities on land and air coupled with its low weight make the robot one cool intermediary step toward that end.
"Creating multi-functionality in robots is difficult without adding lots of different actuators [motors] to the system," says Spenko from his Main Campus office, a heap of robot innards on the floor in front of his desk. "I tasked Arash with creating locomotion in multiple domains without adding more actuators, which would be a big problem for both flying and controlling such a complex system. The type of actuators needed for flying are very different from those used for ground locomotion. In flying, you need high-speed actuators for generating lots of thrust; on the ground, you need low-speed and high-torque actuators."
Kalantari tackled the problem in two parts. He first designed an aerial 'bot with four rotors, hence the quadrotor, and came up with a system that allows the robot to move on the ground using the same four actuators it uses for flying. Kalantari's first prototype was a walking quadrotor aerial vehicle, which won him the Boca Bearings 2012 Innovation Competition for the month of June.
After working out some efficiency issues with that system, Kalantari came up with the idea of floating the quadrotor in the middle of a crash-proof polycarbonate/carbon-fiber cylindrical cage on a pair of revolute joints, using the propulsion from the actuators to roll across the ground. Except for some of the electronics, Kalantari fabricated nearly every part of the HyTAQ in Spenko's Robotics Laboratory.
"The beauty of all this is that Arash's solution is really elegant," Spenko says. "The robot's a ground vehicle where obstacle-negotiation becomes a moot point. You can just fly it right over the problem, which is a big issue with ground robots. And it's an aerial vehicle that solves one of the biggest problems of aerial systems, especially quadrotors—that they are highly inefficient."
In the first phase of testing, the HyTAQ flew continuously for five minutes and traveled 600 meters in that time. On a smooth linoleum floor, the 'bot traveled for 27 minutes and covered 2,400 meters. The HyTAQ is outfitted with a camera, powered by a lithium-ion battery, and operates by remote control.