Researchers at Chiba Institute of Technology, lead by Shuro Nakajima, have unveiled an innovative robotic wheelchair capable of climbing stairs. Simply put, this robot uses its four-wheel drive design to make a variety of movements. That's right, all the user needs to do is tell it which direction to go, using a joystick, and the robot automatically assesses the surrounding terrain and moves appropriately. Continue reading for a video and more information.
"The robot has sensors on its feet, to see if there's anything nearby. It can also see how far it is from a step. It actually has various sensors, and it uses them in combination, to assess how big a step is. Even if the sensors are in error, and the wheels touch an obstacle, the wheel torque can vary, so the robot can use that as back-up, too. In this way, the robot can detect the road surface reliably."
"If a sensor detects a step, the robot calculates whether it can lift that leg. It can't raise its wheels right away, so the steering system at the rear makes preparatory motions to gain stability. When the wheels can be raised stably, the robot lifts its legs."
[Sources 1 | 2]