Projecting a robot’s intentions

A new spin on virtual reality helps engineers read robots’ minds

In a darkened, hangar-like space inside MIT’s Building 41, a small, Roomba-like robot is trying to make up its mind.

Standing in its path is an obstacle — a human pedestrian who’s pacing back and forth. To get to the other side of the room, the robot has to first determine where the pedestrian is, then choose the optimal route to avoid a close encounter.

As the robot considers its options, its “thoughts” are projected on the ground: A large pink dot appears to follow the pedestrian — a symbol of the robot’s perception of the pedestrian’s position in space. Lines, each representing a possible route for the robot to take, radiate across the room in meandering patterns and colors, with a green line signifying the optimal route. The lines and dots shift and adjust as the pedestrian and the robot move.

This new visualization system combines ceiling-mounted projectors with motion-capture technology and animation software to project a robot’s intentions in real time. The researchers have dubbed the system “measurable virtual reality (MVR) — a spin on conventional virtual reality that’s designed to visualize a robot’s “perceptions and understanding of the world,” says Ali-akbar Agha-mohammadi, a postdoc in MIT’s Aerospace Controls Lab.

“Normally, a robot may make some decision, but you can’t quite tell what’s going on in its mind — why it’s choosing a particular path,” Agha-mohammadi says. “But if you can see the robot’s plan projected on the ground, you can connect what it perceives with what it does to make sense of its actions.”

Agha-mohammadi says the system may help speed up the development of self-driving cars, package-delivering drones, and other autonomous, route-planning vehicles.

“As designers, when we can compare the robot’s perceptions with how it acts, we can find bugs in our code much faster,” Agha-mohammadi says. “For example, if we fly a quadrotor, and see something go wrong in its mind, we can terminate the code before it hits the wall, or breaks.”

The system was developed by Shayegan Omidshafiei, a graduate student, and Agha-mohammadi. They and their colleagues, including Jonathan How, a professor of aeronautics and astronautics, will present details of the visualization system at the American Institute of Aeronautics and Astronautics’ SciTech conference in January.

Seeing into the mind of a robot

The researchers initially conceived of the visualization system in response to feedback from visitors to their lab. During demonstrations of robotic missions, it was often difficult for people to understand why robots chose certain actions.

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