Robotics has been rapidly advancing on many new fronts, so it might be easy to forget that there’s still plenty of room for innovation at the most fundamental level of robotics: the hardware. Joohyung Kim’s KIMLAB group, though, has it very much in mind. They have been generating one hardware innovation after another, ranging from a plug-and-play robotic arm, to a backpack robot that provides the wearer with extra arms, to a giant humanoid robot, to a wheel-shaped robot, among others. 

Robotic arms have been available for decades, but they’ve always suffered from a major drawback: they had to be bolted down to tables, or otherwise firmly affixed to heavy structures. Since Kim, who is an associate professor in Electrical & Computer Engineering and the Coordinated Science Laboratory, joined the U. of I. in 2020, one of his top goals has been to create a lightweight, plug-and-play robotic arm that can be easily moved throughout a home to assist with daily-living tasks.

Thus, one of his top current projects is developing “MOMO,” the Mobile Object Manipulation Operator. As shown in videos of prototypes on Kim’s YouTube channel, such an arm could be easily and quickly clamped down to a countertop or table edge so that the arm can, for example, fill a nearby dishwasher or prepare coffee. He’s also attached one of his MOMO arms to a mobile restaurant serving robot the group purchased, so that the arm can move wherever it’s needed without being carried.

One element of the MOMO arm and hand is an innovative 3D-printed “skin” that does double-duty as both a sensor and a way to give the robot a gentler touch.

Kim is fulfilling a lifelong ambition to make better humanlike robots. “That’s kind of my childhood dream, from five years old,” he said. Before coming to the U. of I., he spent years designing robots for Disney. But his robotics hardware, however delightful it might seem to observers, is no longer just for entertainment. 

He says that as his research advanced, he found himself becoming more and more interested in nature and people, and “not just the mechanisms,” as he put it. It gave him a new sense of purpose: “I want to use this robotics technology to help people in daily life,” he said. “That’s my research direction.”

Another major KIMLAB project is the development of a giant humanoid robot. Like robotic arms, bipedal robots have been around for years, but they too have struggled with limitations. In particular, the bigger a robot is, the bigger and heavier the actuators that enable its movement. With traditional bipedal robot design, the actuators have been placed inside or close to the joints they move. Thus, larger robots have had difficulty with locomotion simply because their limbs were weighed down by their own actuators.

Kim’s group solved that problem through optimizations that included a novel way of distributing the robot’s mass. Instead of placing actuators at the leg joints they move, the team located the actuators above the legs, such that the resulting lightweight legs can be controlled at a distance via a linkage mechanism. Through such design modifications, the group has already created a gigantic pair of robotic legs that are 1.84 meters (about 6 feet) tall and weigh only 29.05 kilograms (about 64 pounds)—offering a dramatic improvement over earlier humanoid robots.

Another remarkable KIMLAB creation is the Ringbot, a robot that’s essentially a single rolling wheel with two highly dexterous legs that it can use to steady itself or tip itself upright if it falls over. Yet another is a backpack robot with up to four detachable arms, so that the wearer resembles the Marvel Comics character Doctor Octopus. 

However, “It’s not just a Doctor Octopus,” Kim stresses. For one thing, the backpack robot is currently too heavy to be practical—at least on Earth. At zero gravity, it’s a different story: in outer space, the robot would become weightless, and would easily support astronauts’ work. 

“For now, there is no use, so people think, OK, that’s for a movie or something,” laughs Kim. “But I have plans!”