Wheelchair that can climb steps

Wheelchair that can climb steps

Japanese researchers have developed a robotic wheelchair with legs that can climb steps and negotiate obstacles like walking over a ditch.

Engineers at the Chiba Institute of Technology in Narashino have developed the prototype of a robot wheelchair that can make a variety of movements using four-wheel drive and five axes of motion.

Like any other wheelchair, it rolls along on its wheels but, if a step or ditch gets in the way, the wheels transform into legs to carry the user over, the Daily Mail reported.

The user controls the device by means of a joystick and its robot brain automatically assesses the surrounding terrain and moves appropriately, even adjusting itself to keep ensure the seat remains level. Sensors on the feet of the wheelchair detect if there are any obstacles nearby, researcher Professor Nakajima was quoted by the paper as telling DigInfo.tv.

Using its sensors in combination it can assess the size of an obstacle and how to negotiate it. Even if the sensors fail to detect an obstacle in advance and the wheels touch it, the torque can be automatically varied as a backup.

“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,” Nakajima said.

As well as its ability to negotiate uneven ground, the wheelchair can also line up its wheels and extend stabilisers either side, allowing it to turn in a circle. This makes it easy to reverse even in narrow spaces.

Researchers decided to stick with the conventional wheeled design for their chair, since wheels are the most efficient way of getting around on paved surfaces.
With the prototype ready, they now hope to conduct further tests to perfect their invention.

“For now, we’re presenting this system and form as a concept, and the motion has mostly been worked out. So, we’re at the stage where we can show this robot to the world,” said Nakajima.

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