Kim’s ‘stickybot’ can climb on glass

Stanford University student Kim Sang-bae became instantly famous due to a lizard-like robot he invented. After video images of “Stickybot” crawling against a window were shown on YouTube, a video Web site, an article about Mr. Kim and the robot was published in last month’s issue of Forbes magazine. Time magazine picked the robot as one of the 44 Best Inventions of the Year in its Nov. 13 issue. The robot will also feature in a special PBS program next year.
Mr. Kim is currently pursuing a doctoral degree at Stanford University.
“I got my inspiration from lizards that can stick to the wall and move slowly,” Mr. Kim said.
The robot’s “foot” consists of fine fibers, or polymer pads with synthetic setae. The end of the fibers are slanted to face only a single direction. When the end of the fibers are placed on a window and pulled down, they create a strong friction, allowing them to adhere to the window. However, if the robot is pulled in the opposite direction, it can be detached easily.
“The Biomimetics Dexterous Manipulation Laboratory at Stanford, to which I belong, has been developing a wall-climbing robot. It succeeded in developing a robot that can climb a rough space, but failed in developing one that could climb a smooth surface. So I thought I would develop a lightweight robot that can climb a window,” he said.
Other academics have taken heed of the stickybot because it opened the door to a new theory of “directional adhesive.”
According to Mr. Kim, it was already known through research on geckos, a type of lizard, that there exists a chemical compound that adheres in one direction but can be easily detached in another.
Two years ago, Mr. Kim became interested in the field after reading a thesis by a famous biologist at Lewis & Clark College. Later he was wondering what makes a lizard cling to vertical surfaces. He watched a video of a lizard climbing a wall more than 30 times, he said.
Mr. Kim was born in 1975 and graduated from Yonsei University with a bachelor’s degree in engineering. He said he developed a hobby of making things when he was young. He assembled a remote controlled toy car and produced plastic prototypes. He always represented his school in science contests and rubber band-powered plane competitions. His brother, who is now studying toward a doctoral degree at Purdue University, also gave him inspiration.
Mr. Kim’s father died in a car accident two months after he was born and his mother raised her two sons alone.
“My mother never tried to interfere with our lives or pressure us to pursue her dreams. She always said to do what we liked to do,” Mr. Kim said.
Mr. Kim has completed filing an application for patents for his robot. He already has four patents on a rescue robot he developed last year.
In the future, he wants to teach, he said. “But ultimately, I want to invent something that is of practical use. For example, I want to produce a flying robot. The current observer airplanes or helicopters need to always stay in the air. But if they can stick to a branch of a tree or a wall, they can serve their purpose much longer. I am also interested in robots that can walk but also run on wheels. Those robots can run on wheels when a road is good but they can walk on rough surfaces,” Mr. Kim said.
He added, “The current education system teaches how to solve problems and asks students to follow a method. Most things in the world already have solutions, but the rest are new and need to be solved with different methods. Thus my motto is ‘there is no right answer but a right direction.’”

by Shim Jae-woo , Nam Jeong-ho