h a l f b a k e r y
Poof of concept

idea: add, search, annotate, link, view, overview, recent, by name, random

meta:

account: browse anonymously, or get an account and write.

 user: pass:
register,

 Before you can vote, you need to register. Please log in or create an account.

# Rabbit Racer

Wheel movement propulsion
 (+3, -2) [vote for, against]

To better understand this concept, do the following: Stand a hand on the desktop on its four fingertips. Move the two middle fingers forward. Shift the hand’s weight to those fingers and then slide the outer fingers forward, past and ahead of the inner fingers. Shift the weight to the outer fingers and slide the inner fingers forward. Repeat. The finger exercise is similar to a racing rabbit’s paw movement and is the heart of this vehicle propulsion idea.

Replace the middle fingers with a pair of wheels on a short axle and the outer fingers with wheels on a long axle. The axles can slide in tracks – think linear motor - in a central, horizontal rail so that the wheel-pairs can move towards and past each other and change places (the wide wheel-pair’s axle is above and outside the other’s axle). See the schematic link for better comprehension.

In forward motion the wheels are ratcheted to only roll forward, so the front pair of wheels is motionless while the vehicle-bearing rail is pulling itself forward and the rear wheels roll forward twice as fast. When the wheel-pairs have changed places, the linear motor pulls the axles back towards the center, as the vehicle continues its forward progress.

Thus the wheels aren’t pulling by turning but by standing still on the surface in phases (when not coasting). I know that by having the wheels pass each other, I complicate the axle construction and make the vehicle instable at the instant when all four wheels are in line, but I couldn’t resist it.

 — FarmerJohn, Jan 07 2004

schematic http://www.geocitie....html?1073469123858
The size of the wheels and undercarriage are exaggerated for clarity [FarmerJohn, Oct 04 2004, last modified Oct 05 2004]

Bizarro +
 — k_sra, Jan 07 2004

me thinks that, in motion, this would look a lot like someone just learning how to use the clutch...
 — rbl, Jan 07 2004

I thought this would be Dog inside the track, rabbits outside
 — theircompetitor, Jan 07 2004

You've been watching too many editions of "Robot Wars"!
 — dobtabulous, Jan 07 2004

Volkswagon already produced a "Rabbit". Perhaps Hare Racer? I got nothin' ...
 — Letsbuildafort, Jan 07 2004

Good luck on those tight turns. Any up-and-down motion in this concept, like with the hand example? That lends itself to unfortunate model names which I won't go into here. Top speed would be pretty low; since one set of wheels has to be at rest relative to road in order to apply thrust. Hell on bearings. Ugh. UB Fished.
 — elhigh, Jun 13 2005

 The balancing thing would be a critical problem, I suggest arranging the four wheels into a diamond shaped arrangement, one wheel at the front, one at the back, and two wheels on an axle in the middle of the chassis.

Sliding the axles forward and back again so quickly would require HUGE bursts of energy to obtain a decent speed.
 — BJS, Jun 18 2006

The description of this idea reinforces my impression that [FarmerJohn] was actually a cartoon character.
 — methinksnot, Jun 19 2006

Yeah, but he sure came up with some really cool clocks.
 — NotTheSharpestSpoon, Jun 19 2006

 [annotate]

back: main index