Last year has been presented the manual wheelchair that climbs steps and stairs, for which we received a maker of merit 2018 and an international patent (on google " W.I.P.O. Andrea belli ") this year will be presented a prototype of an electrical 4wd wheel chair capable also of climbing steps and stairs.
This wheelchair is smaller than the previous version ( 85 x 50 cm max) and it is possible to enter it in the elevators and it can be folded and put in a car.
This prototype is entirely built with wood, nuts and bolts, 3d printed parts and it is equipped with two windscreen motors at my home.
If this prototype was made of steel or alluminium it would be cheaper and it would solve the problem of climbing steps and stairs.