Despite many changes over the years, the world isn’t really wheelchair friendly. There are still curbs and steps and other obstacles that need to be surmounted. A team of Japanese engineers have been developing a wheelchair that has greater capabilities to deal with these impediments to mobility.
“The robot has five sensors on its feet, to see if there’s anything nearby,” explains Chiba professor Shuro Nakajima. “It can also see how far it is from a step.”
The five sensors work together to evaluate the terrain. The user only has to adjust the direction using a joystick; the robot does the rest. Using its five axes and four wheels, it automatically adjusts wheel height, smoothly and mechanically elevating up and over just as it reaches a step.
The process might look a little slow and cumbersome, but if you watch the sliding seat and the angling of the wheels, you’ll see the whole apparatus works together to not only overcome the obstacle, but do so with minimum disturbance to the individual who remains fairly level and stable at all times. That means that when the chair comes up against slanted ramps or downward steps, it is constantly and smoothly readjusting the seat level to ensure the user does not get thrown around. It can even step straight over an obstacle while keeping the seat level and elevated.
One of the advantages of the current design is that the appendages can function as either legs or wheels, whichever is the most appropriate for manoeuvring the immediate terrain. The team is working on speeding up the the process and decreasing the chair’s bulk to improve its usability.