WalkNet: Your Posting: @ Fred Hawkins

nomad

WalkNet: Your Posting: @ Fred Hawkins

hi,
excuse my late question:
you wrote:

<<
A leg's motion probably
can be modeled as repeating wave function. I would try to use Bezier curves to define those
waves. They are simple to adjust, even dynamically -- little steps, big steps, fast steps,
slow steps -- merely by adjusting the end and control points and the rate at
which you evaluate your progress along the wave. Then a simple translation of
the curve to a servor control value. Three servors on a leg suggests three curves,
four legs suggests
merely four different evaluation points along the same set of waves.
>>

i am verry interesting on your work!
i am looking for such things....
have you some tips for this waves, (or better, some code-snippets)??
thank's for your help
regards
nomad

Fred Hawkins

Aw shucks. I was just offering an alternative.

But you did provoke me to go downstairs, fire up the Atari 1020 ST, determine that neither the Syquest removable hard disk nor the mouse works. But I did find a 3 1/2 floppy that did contain a June 1992 article I wrote about Bezier curves which I entertained sending to Dr. Dobbs when it was still a fun read. It probably reflects the sum of my actual knowledge. So I printed it on the Epson LQ 800 (24 pin head with the last known ribbon in the world with the last known box of microperfed continuous feed paper.
Had to relearn how to feed the paper too. Computers were tougher then.)

I might be able to get it off the floppy but probably I will need to type it all.

Let me re-read what I had to say about B.curves back when I was smart[noparse][[/noparse]er].

Fred

nomad

hi Fred
thanks for your answer,
in the old day i have a commandore C64 its was great....
at the time, i am looking in the web, for some c-code for bcurves.
in the next few days i write some c-code and hope thats running.
thanks and regards
nomad

Fred Hawkins

nomad said...
hi Fred
thanks for your answer,
in the old day i have a commandore C64 its was great....
at the time, i am looking in the web, for some c-code for bcurves.
in the next few days i write some c-code and hope thats running.
thanks and regards
nomad

Here's the text. Cautionary note, it's not a complete article but it does do some heavy lifting before bogging down. What is not there is my conclusions about Bezier curves aka spline curves. Understand it's just an engineered curve -- a way to weight the influence of the control points upon a line that goes·between two endpoints. In my article, I was mostly concerned with getting a curve on a screen or into a printer.

There's nothing to prevent you from making up your own matrix that does the weighting and tailoring both the matrix and "curve" that defines your motion problem to suit your device.

If you do get interested in these curves, try to do the 'under the hood' graphs on your own to·SEE how the parts of the matrix change from one end of the curve to other.

Fred

Post Edited (Fred Hawkins) : 7/19/2007 6:21:01 PM GMT

RinksCustoms

I don't go that far back, but i do remember Overclocking a few 386 IBM machines in electronics engineering class - translated, messin with the jumpers, got it running WAY faster than it was designed to, played the fastest QDOS games around for a whole five minutes until the proccessors caught fire, lol What?! We were 17..

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
E³ = Thought

http://folding.stanford.edu/·- Donating some CPU/GPU downtime just might lead to a cure for cancer! The average PC while browsing the internet typically uses less than 30% of it's potential, why not donate a portion of the rest for cancer resaerch?

nomad

hi
@ fred:
thanks for the text. its hopeful.
thanks for your help

@RinksCustoms:
yeah
you know instead of 5 1/3 floppy -> audio-tapes as disks?

regards
nomad