Re: [CAD_CAM_EDM_DRO] Re: Open (i think) design for a parallel robot (reprap may be interested)

From a Machinists view and knowing basically what is required for general machining. The Stewart platform, although clever and innovative would have to be built on a massive scale to even be adequate for modest machining including plastics. The key is mass and close tolerance and even resistance in the ways can add to the stability.

From a programming standpoint it would be a challenge. It would be an absolute production and choreography just to move the table two inches and keep it in a straight line and on the same plane radially, square to the spindle etc. Folks have enough trouble getting their cartesian machines to even cut a round circle without backlash etc., can only imagine the issues that would be involved with six actuators attempting to position a table aloft.

These designs are fun to discuss, but the reality is they are way out of the loop for the home shop. Hotwiring styrofoam possibly, but not even machining plastics.

Just my opinion, Ron

Graham Stabler <eexgs@...> wrote:
--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Dennis Schmitz"
<denschmitz@...> wrote:

>In any case, this also appears to be compatible with the
> goals of the reprap project. It seems that this design would be
>simpler to build than a cartesian positioner, and since reprap

doesn't >require the rigidity of a mill, this might be a more
versitile design.

No way, a hexapod is a can of worms. Software, calibration, joint
accuracy, singularities etc etc

Plus you need 6 motor drivers and motors and you don't even need
6-axis control.

A triaglide perhaps but not hexapod. Especially an unproven virtual
design (as far as I can tell)

Graham






[Non-text portions of this message have been removed]