Square-wheeled robot design will help propel MEMS, not CARS
posted Dec 5th 2005 4:30PM
You probably won't see this "breakthrough" tech at your local Beemer dealership anytime soon, but researchers from Troy, NY-based Distributed Robotics have (please excuse the pun) stumbled upon a new method of locomotion that uses a rotating weight to slowly propel a vehicle with square wheels. Now more than just the subject of Far Side cartoons, the prototype square-wheeled crawler uses a motor to horizontally drive a weight around each of the four interdependent wheels (which are slightly offset from one another), moving the vehicle forward as the wheel underneath the weight falls flat to the ground. Rather than trying to get NASCAR interested in their technology, Distributed Robotics and partner Global Composites envision a more nano-scale, MEMS-use for this system, which when scaled down could also theoretically work using hydrodynamic, magnetic, electromagnetic, or electrostatic forces instead of gravity.
[Via RPTT]
hehe. reminds me of canadian cars in south park.
boring! square wheeled vehicles have been around for a long time, you just need to drive them on a surface composed of catenaries (http://stanwagon.com/)
[insert polish joke here]
It's that same falling forward tech as used in the segway. And walking.
I still don't see how it works though, from this picture. Maybe linky has the vids.
Wry - the Segway uses forward momentum to start it's moving process, this is entirely different
Although it's neat to see how they accomplished this, I fail to see how this application in movement can be anymore efficient than round wheels.
2nd Wry - you are right about walking though. The spinning weight is akin to your arms swinging and your hips shifting weight from one foot to the other.
You can see THAT baked into the robosapien line of robots in the way they move.
Can you not see? It seems fairly obvious..
At one point in time one set of wheels(say the front)are flush to the floor whilst the back are on the point of their square wheels.
Whilst the front wheels are flat on the surface, the weight would be forwards.
As the weight swings around, the gravity would push the vehicle down on the back and put more presure on the back wheels to turn to a flat position, this would in turn make the front wheels rest on the corner of the 'wheel'.
Hope that makes sense.
It seems like good technology as it is also using gravity to move. It is much easier to make things move in a circle horizontally than conventional propulsion.
I think by now you can tell im hardly a scientist or anything.
Sorry, also there is less opposing forces on the circular motion as it is not acting against gravity, therefore will require less force itself to move.
If you look carefully, you will notice that even the wheels on the same axle are not aligned. If I had to guess, the front left wheel is flat on the surface, the front right is 22.5 degrees from flat. The rear right is 45 degrees from flat, and the rear left is 77.5 degrees from flat. The weight looks like it is turning clockwise. When the weight reaches a point just beyond the midline of the car the front right wheel will rotate forward 22.5 degrees so that it is flat on the floor. At that point the rear right will be 22.5 degrees from flat, the rear left will be 45 degrees from flat and the front left will be 77.5 degrees from flat. This pattern will repeat, each wheel turning 22.5 degrees at a time, with four of these movements for every 360 degree rotation of the weight.
....Excuse my ignorance but....
Why not use circular wheels?
They do have a history of working don't they? Why change an obviously better system?
I don't know, it just seems like a stupid thing to do.
http://www.globalcomposites.net/
video ^^
Since when were circular wheels the better system? They can't even get up stairs.
"Since when were circular wheels the better system? They can't even get up stairs."
You've obviously never seen jeeps on the trails near Moab UT.
jeeps at moab...
http://www.4x4now.com/mtmm.htm
You are correct about the 22.5 degree phase shift from wheel to wheel, click on description at www.globalcomposites.net for a pdf file. If the (4) wheels were triangular, the phase angle would be 30 degrees. If there were 3 square wheels, the phase would also be 30 degrees. 4 pentagons the phase is 18 degrees. There is a definite pattern for regular polygon wheels. Hope this helps.