Turning model ?

[walker1]

Not quite sure where to post this.

If one has a scooter (two wheels) with a known overall length, wheel base and width, how do one calculate / plot the path it takes during a sharp 90 degree turn?

Or in other words:
Can I roll it into this holding area without having to lift it to get around that corner ?

Is there a simple math model for this ?

A link would be welcome, but so far I have found none. Maybe because I asked Google the wrong questions

 

[NormPeterson]

Sounds a little like half of an Ackermann construction. Assume that the front and rear wheels are purely rolling along the circumference of the same circle and that you aren't leaning the thing over at all. Then plot the inner and outer "tracks" of scooter width about the center of the circle to determine the required path width.

Norm

 

[walker1]

But the thing is, that the front wheel (turned 45 degrees) will follow a much wider turn, than the rear.

I have tried to simulate it in exel but my result was an ever increasing spiral. (Which I do not believe to be correct!)

We are more into the (fun ?) math here, as I do not think I can roll the thing in there without lifting it around one specifically tight corner.

Oops. Just came to think about one thing.
The two circles must be linked, and the difference in radius must be 0.707 times the wheel base at 45 degrees.
Now I only have to find one radius, then I can start plotting. But how to find it?

 

[NormPeterson]

Make that two circles with the same center. Front wheel circle radius is the hypotenuse of a right triangle whose opposite side is the wheelbase and angle is the same as the steer angle. Rear wheel circle radius is the adjacent side.

Or you could lean, steer, and stomp on the rear brake only as you approach the storage area and skid the back end around a bit (remembering my coaster-brake bicycle days).

Norm

 

[walker1]

That is exaecly what I just found out myself

Things are at times so simple, if you only get the right idea to begin with!

 

[walker1]

Now the sad part is, that my turning radius will be way too wide, as I expected.

But we will see, when the time comes. Now I know, what to expect.