"Who is Bram Stoker?" Those three words demonstrated the amazing potential of Artificial Intelligence. It was the answer to a final question in a particularly memorable 2011 episode of Jeopardy!. The three competitors were former champions Brad Rutter and Ken Jennings, and Watson, a super computer developed by IBM. By answering the final question correctly, Watson became the first computer to beat a human on the famous quiz show.
"In a way, Watson winning Jeopardy! seemed unfair to people," says Jeehwan Kim, the Class '47 Career Development Professor and a faculty member of the MIT departments of Mechanical Engineering and Materials Science and Engineering. "At the time, Watson was connected to a super computer the size of a room while the human brain is just a few pounds. But the ability to replicate a human brain's ability to learn is incredibly difficult."
Kim specializes in machine learning, which relies on algorithms to teach computers how to learn like a human brain. "Machine learning is cognitive computing," he explains. "Your computer recognizes things without you telling the computer what it's looking at."
Machine learning is one example of Artificial Intelligence in practice. While the phrase "machine learning" often conjures up science fiction typified in shows like "Westworld" or "Battlestar Galactica," smart systems and devices are already pervasive in the fabric of our daily lives. Computers and phones use face recognition to unlock. Systems sense and adjust the temperature in our homes. Devices answer questions or play our favorite music on demand. Nearly every major car company has entered the race to develop a safe self-driving car.
For any of these products to work, the software and hardware both have to work in perfect synchrony. Cameras, tactile sensors, radar, and light detection all need to function properly to feed information back to computers. Algorithms need to be designed so these machines can process these sensory data and make decisions based on the highest probability of success.
Kim and the much of the faculty at MIT's Department of Mechanical Engineering are creating new software that connects with hardware to create intelligent devices. Rather than building the sentient robots romanticized in popular culture, these researchers are working on projects that improve everyday life and make humans safer, more efficient, and better informed.
Jeehwan Kim holds up sheet of paper. If he and his team are successful, one day the power of a super computer like IBM's Watson will be shrunk down to the size of one sheet of paper. "We are trying to build an actual physical neural network on a letter paper size," explains Kim.
To date, most neural networks have been software-based and made using the conventional method known as the Von Neumann computing method. Kim however has been using neuromorphic computing methods.
"Neuromorphic computer means portable AI," says Kim. "So, you build artificial neurons and synapses on a small-scale wafer." The result is a so-called 'brain-on-a-chip.'
Rather than compute information from binary signaling, Kim's neural network processes information like an analog device. Signals act like artificial neurons and move across thousands of arrays to particular cross points, which function like synapses. With thousands of arrays connected, vast amounts of information could be processed at once. For the first time, a portable piece of equipment could mimic the processing power of the brain.
"The key with this method is you really need to control the artificial synapses well. When you're talking about thousands of cross points, this poses challenges," says Kim.
According to Kim, the design and materials that have been used to make these artificial synapses thus far have been less than ideal. The amorphous materials used in neuromorphic chips make it incredibly difficult to control the ions once voltage is applied.
