Good Thinking

Scalevo wheelchair uses retractable tracks to climb stairs

Scalevo wheelchair uses retrac...
The Scalevo wheelchair at its first public demo
The Scalevo wheelchair at its first public demo
View 3 Images
Upon reaching a flight of stairs, the Scalevo's twin rubber tracks descend from its undercarriage to carry it over them
1/3
Upon reaching a flight of stairs, the Scalevo's twin rubber tracks descend from its undercarriage to carry it over them
A rendering of the planned finished product
2/3
A rendering of the planned finished product
The Scalevo wheelchair at its first public demo
3/3
The Scalevo wheelchair at its first public demo

We've seen tracked wheelchairs before, that are able to take on steep or uneven terrain. For regular surfaces, however, wheels make more sense. That's why a group of students from ETH Zurich and the Zurich University of the Arts are creating the Scalevo electric wheelchair, which features wheels for cruising and tracks for climbing stairs.

When on smooth ground, the Scalevo balances Segway-style on its two wheels – this setup aids in agility, allowing it to make sharp turns. Upon reaching a flight of stairs, however, its twin rubber tracks descend from its undercarriage to carry it over them. In order to keep the user level while this is happening, a set of pistons tilt the chair back relative to the tracks, compensating for the slant of the stairs.

The mechanical and electrical engineering students now have a working prototype and are planning to use it next year in the Cybathlon, an ETH-sponsored race for disabled athletes using assistive devices. There's no word on whether or not they plan on commercializing the technology.

The wheelchair can be seen in use, in the video below. Although it climbs stairs pretty slowly right now, the team hopes to ultimately attain a speed of one step per second.

Source: Scalevo via DamnGeeky


6154

3 comments
Roger Garrett
Dozens of stair-climbing wheelchairs have been designed over the years. None have ever made it to market.
Daishi
This is cool. Another method of doing this can be seen in this hand truck here: https://www.youtube.com/watch?v=0PpNLD3TrdE A company called sterraclimb makes an electric 6 wheeled hand truck that is similar and someone did a kickstarter called "UpCart" last year using a similar design. Another possability to do this with a 4 wheeled vehicle is something like the Outrunner robot: http://www.gizmag.com/outrunner-running-robot/31999/ It's purpose is to be a fast legged robot but a similar "legs as wheels" design could also likely be used to climb stairs cheaply. You could even build them to be retractable so it operates as a regular wheel most of the time. These guys explored a similar concept to Outrunner: https://www.youtube.com/watch?v=hBFf0pZjY94 Tracked robots with flippers like iRobots packbot can also climb. There are a couple of other tracked stair climbing bots here (https://www.youtube.com/watch?v=dgJ1nHu-hOo) and here (https://www.youtube.com/watch?v=bCEglW9e5EQ) The flippers on the iRobot packbot are useful for getting the right position on the first step and after that the tracks just drive up. There are a handful of other methods too really.
Dave Weinstein
It's cool that companies are working on this, but it seems like it's a step backwards. Deka Research was doing this more elegantly over a decade ago (http://www.dekaresearch.com/ibot.shtml), and in fact it was covered by Gizmag then! http://www.gizmag.com/go/4380/ It's a shame that iBot was never able to reduce the manufacturing cost enough to make it a mainstream product. It was, however, a shipping product that DID make it to market, and I have a friend that actually has one (and has used it to climb stairs).