Precise X-Y positioning table with ONE drive element/actuator

[FaysalAli]

Title says it all. This video illustrates what I'm trying to make:

https://www.youtube.com/watch?v=VH-uysb4W0c

Basically the upper part of the device has a degree of freedom of 2, namely x and y axis and the lady is controlling the movement with a single joystick. What kind of guide or bearings would be used to construct such an appliance? Please keep in mind that I am only interested in the mechanical elements that make this movement possible.

Answers would be much appreciated!

 

[GregLocock]

How do you know there is only one actuator? It can be done, but I doubt it is cost effective.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[itsmoked]

No way that's one actuator. More like three (3).

Keith Cress
kcress -

http://www.flaminsystems.com

 

[ScottyUK]

One joystick incorporates the input transducers for at least three axes, and probably other functions which are not X-Y-Z axis controls. It's highly unlikely to be a single actuator, more likely three ballscrews and precision slides.

 

[BUGGAR]

You could "fake it" with a pantograph mechanism. A spring plunger (or screw as shown) in the joy stick could control Z axis action.

 

[btrueblood]

I'm not sure there is an actuator for the x-y motion of the device (using z as the vertical or gravity axis in my little world), the base moves on its table "actuated" by the doctor's hands. The joystick controls the level of the patient's head via chin rest and and associated actuator, and the focus of the optics via another. At least, that's how the one in my opthalmologist's office works.

 

[Screwman1]

The many times that I have been on the patient side of those, the "joy stick" is just a friction drive ball that moves the mechanism by pivoting on the surface of the table. The technician slide it across the table surface to switch eyes. Strictly friction, pivoting on the surface of a ball on the end of the handle.

 

[SnTMan]

Yeah, looks like the tech lifts the back (or is it front?) of the thing to switch eyes.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand