The PalmPuk (with MS Paint graphics)

[TheSoulhunter]

So, I got an idea I want to share with you...


The PalmPuk

A sliding palm rest that lets you move your hands without lifting them.
It is basically a combination of resting and hovering...


The device consists of two main parts:




Upper Part (with cushion pad) -> Where your palms or the base of your hands rest.
Lower Part -> Contains three captive steel balls arranged in a triangle.
The upper part glides smoothly on these balls in two axes...




This should create a low-friction "hover" effect...
Your hands stay supported, while the whole assembly slides with your natural hand movements.

It should feel like your hands are floating...
Combining the benefits of a palm-rest with the freedom of hovering.


This probably only works for 60% size boards... and split-ergo ones...
The perfect size of the Puk, the freedom of movement, and the exact design...  have to be worked out.
If someone wants to produce the PalmPuk, feel free to do so (credit and free sample would be nice tho).


What do you think? Input? Criticism? Suggestions?

[TheSoulhunter]

As tipping might be a concern in the extended positions,
flipping the design upside down might be a good idea...

[TheSoulhunter]

If we use split spherical bearing seats, machining would be easier,
and we could use a soft base-material like Aluminum...




Or does someone have a better idea for the seating?

[vvp]

The bearing ball must be touching directly the table (or some big pad (cushion) put on the table) to provide easy movement. Your design provides easy movement only withing the cushion area which is drawn about the same size as the whole device for one hand. Also the balls must be able to move around in the device if you want to use only rolling friction. Your proposal does not handle this at all.

You can provide easy "friction less" movement with magnets (magnetic levitation), air cushion (you need air pump somewhere), ultrasound levitation or some omnidirectional wheels touching directly to the table.

But if you are lazy to move your hands around then you can also get a keyboard which does not require any palm movement while typing, like e.g. K80CS: https://deskthority.net/viewtopic.php?p=250605#p250605

[TheSoulhunter]

The bearing ball must be touching directly the table (or some big pad (cushion) put on the table) to provide easy movement. Your design provides easy movement only withing the cushion area which is drawn about the same size as the whole device for one hand. Also the balls must be able to move around in the device if you want to use only rolling friction. Your proposal does not handle this at all.

In the second design, the ball is captive in the upper half (blue color, with orange cushion on top) where the hand rests on.
The upper part slides in the lower part which is basically a cup (grey part...).
So, the balls roll on a stationary (non moving) metal base.
This allows the upper part to slide...

The size difference between upper and lower part dictate the freedom of movement.
The balls are held in the bearing surfaces (pink) that sit in the upper part (blue/cyan).
You can simply lift the upper part (which holds the balls) out of the lower part (grey).
This allows cleaning or lubricating the inside of the lower part.

In the first version it's the same, just reversed...
Balls are held captive in the lower part, and the upper part rides on them.
But, as mentioned, this would make the upper part tilt in extended position (moving to the outside).

The goal is to be able to slide your palm about 1 Inch in all directions...
On a 60% board, resting your palms on a palm rest, fingers on home row, about 1 inch is all it takes to reach any key.
The Puk is not meant to slide your hands across the table (going Alphas to Numpad or similar) but just for typing in the Alpha-Area.

Hope this makes it more clear...
Maybe I should make a animation or something?

[TheSoulhunter]

But if you are lazy to move your hands around then you can also get a keyboard which does not require any palm movement while typing, like e.g. K80CS: https://deskthority.net/viewtopic.php?p=250605#p250605

Com'on, It's no about laziness, but ergonomics...
Hovering your hands over something for 6, 8, 10 hours a day, can be straining and lead to problems.

That said... Nice project! Still got the original ErgoDox (from the GB here) sitting in my collection.
Also plan to test one of these Cyborg keypads soon...

Still, this is about a palm rest. One that lets your palms slide in all directions slightly.
Because stretching your fingers is usually not enough to reach all of Num-row (from Home-row).
The Puk would also work for split-ergo boards like the one you made. It's just a different form of palm-rest.

[vvp]

The goal is to be able to slide your palm about 1 Inch in all directions...

If that is the goal then the lower part must be bigger by 1 inch in all directions compared to the upper part. The pictures do not indicate that at all.

Also the picture indicates that the ball sits in the upper bearing depression:
1) if the depression is simple spherical cutout then you will get sliding friction there and it is likely to be too much for smooth motion (even if it is made from a low friction material like e.g. teflon)
2) if the depression is a groove (shown from the direction of the groove ... therefore seen on the picture as a simple spherical cutout) then it will allow easy movement only in one direction (the direction of the groove)

If you want to have a friction less feeling with balls then the balls must be able to move as well. E.g. to move the pad to the right by one inch the ball must be able to move to the right by half an inch! This is true for any direction.
You do not have any indication in your pictures that you allow for this.

Look .e.g. at this exploded view of a linear bearing:

Notice that the bearing balls are there in "squished" loops. The balls mus be in loops since one side of the loop provides the return path for the moving balls. The other side of the loop actually is the working area. This is the area where balls provide friction less movement between the carriage a the rail. They provide the friction less movement by rolling between the rail and the carriage surface. But because of this rolling they are also moving along the loop. Therefore they need the return path. The balls are exiting the working area of the loop ... returning through the return path  and entering the working area on the other side.

Balls move through the working area without friction since they are rolling. This is also the area where the balls are under load (possibly high forces between carriage and rail). The balls are not moving without friction in the return path. But the friction is very low there since there is no load on the balls.

Your design does not address the moving ball problem at all. That is the reason I pointed out other options (magnetic levitation, ...).

[Findecanor]

Interesting, I have previously seen sliding palm rests of plastic/foam with teflon pads underneath. A premium variant of that concept would be something.

I have also had a pair of "ErgoRest": rests on mechanical arms clamped to the desk's edge, that allowed some movement. However, if you stretched the linkages too far, they instead provided resistant to sideways movement, so I found them to be more of a nuisance than help.
I think I had found them at a thrift store, and gave them away to a board member.