An AI table server in Korea is easing coronavirus concerns at a restaurant, Reuters reported. Diners can order through a touchscreen on their table and the robot brings their food to them shortly after. Robots use many sensors to do jobs.
A recent Reuters article told the story of an inventive way for restaurants to stay open during the coronavirus pandemic. “‘Aglio Kim,’ a trolley-like robot which uses artificial intelligence (AI), is delivering food to customers at a restaurant in Seoul, in order to minimize human contact and maintain social distancing,” the article said.
“Shortly after customers order through a touchscreen on the table, the 1.25-meter-tall robot, developed by South Korean telecoms company KT Corp, brings the food and uses its visual SLAM (simultaneous localization and mapping) capabilities to avoid obstacles and navigate around customers. The robot can deliver food to up to four tables at once, KT’s AI Platform Business Team leader Lee Young-jin told Reuters.”
Whether working in a restaurant, hospital, hotel, or other business location, mobile AI robots use any number of sensors to gauge their whereabouts and distance from objects.
“Potentiometer” Is a Real Word?
It can help to get a clear definition of what a sensor is in terms of robotics.
“A sensor is any device or mechanism that registers something happening in the world and converts that event into a signal that can be transmitted to other parts of the robot,” said Dr. John Long, Professor of Biology and a Professor of Cognitive Science on the John Guy Vassar Chair of Natural History at Vassar College.
“Sensors respond to many different kinds of events—everything from changes in light to the presence of dangerous gases. In this day and age of electronic systems, sensors convert their response into a common currency: an electrical signal that the robot’s computer can read.”
Dr. Long mentioned sensors that detect changes in light. Those are called photoresistors. Meanwhile, a potentiometer is a variable resistor that can be used to signal a rotational position. Potentiometers are used as part of a feedback system to help a servomotor maintain precise control of its motion.
Other Kinds of Sensors
Photoresistors and potentiometers serve their purposes well, but what about other types of sensors in robotics?
“An accelerometer […] can convert mechanical vibrations caused by acceleration into an electrical signal,” Dr. Long said. “They actually work by having tiny microelectromechanical accelerometers, things that are common in our smartphones and in our robots. They work by converting the deflections of tiny cantilevered beams with a mass at the end into a change in electrical voltage.”
Microphones also play a part in robotics. Dr. Long said that microphones take sound pressure waves and convert them into electricity. He said they do this by vibrating an internal membrane that’s in the microphone, which then causes a small internal magnet to oscillate and induce a change in an electromagnetic field.
Finally, some robots use digital compasses.
“A digital compass is a tiny magnetometer that is sensitive to the Earth’s magnetic dipole and converts that field that wraps the whole Earth into an orientation relative to magnetic north,” Dr. Long said. Robots with digital compasses can actually navigate using compasses.
KT Corp, who makes the table-serving robot, is planning to roll out a new model next year that uses voice recognition technology.
Dr. John Long contributed to this article. Dr. Long is a Professor of Biology and a Professor of Cognitive Science on the John Guy Vassar Chair of Natural History at Vassar College. He also serves as the Director of Vassar’s Interdisciplinary Robotics Research Laboratory, which he helped found in 2003. Professor Long received his PhD in Zoology from Duke University.