Wire based stewart platform

[JBV]

This would be interesting to try!

A stewart platform hanging from the celing with wires instead of actuators. When not in use you would raise it and free the space below!

The uses could be:
Plasma/gas cutting.
Mig welding.
BIG printing.
Hotwire foamcutting.
Edm sinker.
Assembly.
Soldering.
Sorting.

The "winch" on the wall would be very simple to build! As the nut and wire is always in tension by the platform weight there would be no backlash, even with cheap threaded rod and a ordinary nut. Think this would work?

The controls are:
numpad:
4 & 6 - X
2 & 8 - Y
1 & 7 - Z
Up & Down - A
Left & Right - B
Enter - Run Gcode
Mouse left - pan
Look with the mouse

/Jay

[heyarnold]

Wow! What a concept!

What would be used to guide the wires down towards the platform from the ceiling? Pulleys? Eyebolts? Thin wire probably would not have too much friction that would prevent it from moving freely.

[Zathras]

I get a memory access violation running the app.

[JBV]

I was thinking of polished tubes that you bend and attach to the square tubing. But it should be easy to experiment with different solutions

[miljnor]

The machine would have to be real slow or have some way to stop the swinging ossilations created by stop/start movement.

How would you deal with that?

[JBV]

Check this out!

"The amount of force a robocrane can exert in any direction is equal to the amount of preload"

It seem that with a heavy enoug platform you could even do milling That would be cool

[JBV]

More info Check the machining part!
http://www.isd.cme.nist.gov/projects/robocrane/

[loves80z]

Is there a problem with moving it x or y without moving it Z?

[JBV]

Nope it uses inverse kinematics to calculate the length of the wires. The actuator resolution decides how big x, y & z steps the platform have to move. It will not move in a straight line (if you look close) but as these steps is very small it don't make any damage

I made a small test today! just some wires and a wooden platform to test the rigidity! Seems very nice! Have to try with steppers when i get some controllers

/Jay