PLUM matrix keyboard

[jacobolus]

Has anyone used one? Any thoughts?


Wikipedia: https://en.wikipedia.org/wiki/PLUM_keyboard
PCMag review: http://www.pcmag.com/article2/0,2817,1401569,00.asp
Computer Power User review: (at the internet archive)
Random forum review: http://www.hardwareheaven.com/community/threads/plum-keyboard-the-best-layout-ever.177078/
Defunct homepage: http://web.archive.org/web/20080313121843/http://www.plum.bz/products.html

(note to the mods: I pasted this as a topic a few months ago but it got stuck in some kind of moderation queue)

[SonOfSonOfSpock]

I reminds me of the TypeMatrix. That's interesting about the layout being easier for first-time typists. I wonder if all the new layouts should focus on something like that rather than optimizing movement, etc.

[yasuo]

layout very good it seems
but matrix better on split

[jacobolus]

I think it’s a bit of a waste to put the return key on a thumb, but the shift keys are in IMO a nice spot (better than the standard shift location if you ask me). The ctrl keys, backtick/tilde, escape, minus, equals, all the F keys, and some of the numbers are still in hard to reach places.

I’m not sold on the overall letter layout, but it’s sorta interesting.

One feature is that this would be very easy for someone to build (and also play around with layouts), because except for the thumb keys it’s all 1u keys with the same keycap shape.

[SonOfSonOfSpock]

One of the Cherry Access-IS board might be a good starting point if you wanted to make your own PLUM.

[dusan]

Pros:

* Matrix layout is a big improvement, especially for typing on the bottom row under the left hand.

* The Shift keys are at excellent position for typing.

Cons:

* The entire punctuation column under F12 is hard to reach.

* Ctrl, Alt and Shift too far from arrows, Tab, Backspace, Enter, making it hard for editing (navigation, selection and correction) with one hand.

* Only half space bar, without the possibility to swap Space with Enter, making it hard for typists who use left thumb exclusively or both thumbs with the Space bar.

* The blank (unused) keys contribute nothing but confusion and disorientation.

* Asymmetrical alphanumeric array (i.e. there are more keys under the right hand than the left hand).

* The unusual (non-QWERTY) alphanumeric layout.

Overally, this keyboard has introduced few technical improvements but many changes against standard keyboard. A guaranteed commercial failure.

[dusan]

[ Specified attachment is not available ]
A constructive version of my answer.

[jacobolus]

A constructive version of my answer:

Show Image

Have you tried printing this out and fitting your hands on it? That spacebar looks like a really hard to reach spot, to me.

edit: nevermind I was looking at the little orange space indicator. I’ll have to think about this one a bit.

I don’t really understand all the colored sub-legends.

[dusan]

A constructive version of my answer:

Show Image

Have you tried printing this out and fitting your hands on it? That spacebar looks like a really hard to reach spot, to me.

That's my dilemma.

Statically, on a physical matrix (the TypeMatrix 2030), my thumbs sit exactly there, i.e. left thumb under B and right thumb under N.

Dynamically however, the shiny trace of my thumbs on the space bar are about 1.5x wide, the trace of the left thumb is under VB, and trace of the right thumb under NM.

My guess:

a) 1x wide thumb key should suffice since lateral movements are reduced (due to relocation of the Shift keys).

b) Users still have to adapt a bit (0.5u) to the Space and white Backspace keys. Whether this adaptation is easy remains to be seen. Meantime I rely on the Planck keyboard layout where the designers reported successful adaptation.

edit: nevermind I was looking at the little orange space indicator. I’ll have to think about this one a bit.

I don’t really understand all the colored sub-legends.

The bottom left 2x4 cluster contains Undo, Backspace, Insert, Delete, Redo, Cut, Copy and Paste respectively.

The bottom right 2x4 cluster contains Home, Up, End, PgUp, Left, Down, Right, PgDn respectively.

The two clusters, together with the respective parts of the blue and violet Fn layers, are mutually exchangeable under action of the L <-> R lock (blue Fn + F10).

Certain keys are transposed (i.e. they change position) under action of the left Ctrl (red) or the right Ctrl (orange) key.  This is to move modifier keys closer to the Ctrl key for better one-hand keyboarding. The transposition can be disabled by the Game lock (Fn + caps).

More specs will follow soon.

[dusan]

I've drafted the case that can be made from two metal sheets. It is shown together with a (symbolical) plate and PCB.

DIMENSION:

Inner (key space) dimension: 6u x 16u x 8.5 mm (1u = 3/4 " = 19.05 mm)

Outer dimension: 151.8 x 319.8 x 17.5 mm.

Metal sheet thickness: 0.5 mm

Bend radius: 0.5 mm for horizontal (X axis and Y axis) bends, 2.5 mm for vertical (Z axis) bends.

Screw hole diameter: 3 mm.

WEIGHT:

Plate: 230g stainless steel, or 80g aluminium, assuming 1.5 mm thickness.

Case (not including bolts and nuts): 340g stainless steel, or 120g aluminium.

[vivalarevolución]

Looks awful.

[jacobolus]

Looks awful.

Geez, so mean.

I haven’t ever seen anyone try to make a case out of bent sheet metal like that. Looks pretty interesting.

[vivalarevolución]

Looks awful.

Geez, so mean.

I haven’t ever seen anyone try to make a case out of bent sheet metal like that. Looks pretty interesting.

Oops.  I meant the keyboard and its layout.

The case thing and dusan's ideas are certainly interesting.

[dusan]

I've changed the design a bit.

The reasons are threefold:

• Aesthetic. We may now use countersunk (flat head) screws for the external connections.
• Easier production. All three parts are now made from the same metal sheet (of 1.5 mm thickness).
• Mechanical strength. Now it can withstand about 300 kg bending force and 75 kg twisting force,  theoretically, if made from a high-strength aluminium alloy.
  

DIMENSIONS (update):  Outer 324 x 144 x 18.5 mm. Inner 306 x 115.5 x 8.5 mm.

WEIGHT (update): 480 g (aluminium), including the key plate, not including screws and nuts.

[dusan]

This is the revised layout. The order of Undo, Redo keys and the position of the tenkey pads have been changed.

[dusan]

The layout has passed further development quickly. We can now drop modifier re-location (i.e. pressing a modifier key like Ctrl also moves another modifier key like Shift, Alt, Fn to other position). The only exception is the Shift key becoming Ctrl+Alt under action of the same-hand Fn key, which is to make sure that even three-modifier combinations (Ctrl+Alt+Shift+key) can be typed with only two modifier keys. Note that re-location can always be disabled by the Game lock.

The decision was based on thinking of how users type a complex combination (e.g. Ctrl+Shift+Right Arrow or Ctrl+Alt+Delete) on the standard keyboard. Certainly they type either

a) with both hands; or

b) with the right hand only.

With two configuration locks Ctrl <-> Shift (swaps Ctrl and Shift) and Alt <-> Fn (swaps Alt and Fn) which are already available in the layout, users of either kind can make the modifier cluster that fits their needs, i.e. resembles [almost] exactly the part of the standard keyboard that they're used to. All their good skills and experiences with the standard keyboard are thus preserved. Modifier re-location, therefore, was found unnecessary.

Note that the Alt<->Fn lock also load the alternative function layers which can be defined to fit the new position of Fn keys.

[dusan]

This is the update version of the layout.


Summary of changes:

1. In the center, the Num and Caps locks are positioned closer to the hands, to be hit easily. The F1 through F12 keys are re-arranged into a T-shaped cluster with F1, F4, F5, F8, F9, F12 being corners, to be hit easily if a different keycap profile is used.

2. In the bottom right corner, the Right arrow is now positioned in the same column as Left arrow and End in the same column as Home.

3. Similarly, in the bottom left corner, Cut and Paste are now in the same column, Backspace and Delete are now in the same column.

4. In the thumb area, the Shift key and the f key (Function) are swapped. The new position is better for the Shift key as it is accessible by thumb, with a proper keycap profile.

[dusan]

So finally I reached this layout. With 5 thumb keys in a compact 2x3 array.

Note that swapping Alt <-> Fn (Fn is depicted as 'f') so that Alt in the same row as Ctrl is a 'standard' variation and not a new layout. I use Windows, where this variation feels more natural. The swapped order makes it easier to press by one hand, for example, Shift+Alt+arrow (combinations to select a rectangle region of text in editor Notepad++).

Edit: updated pictures with the correct version number.

[dusan]

And this is the keyboard where I conducted experiments.

EDIT: added a variant, with each 2u vertical key replaced by 1u key + 1u empty space. My thumbs feel better on this variant.

[dusan]

This update is specifically aimed at optimizing the the 2x4 block at the bottom left corner of the layout. It was re-designed to be intuitive. The most pleasuring consequence (and to me surprising) is that one can now remove 2x2 keys at the bottom left corner and symmetrically 2x2 keys at the bottom right corner (if he/she likes to) and still obtain a reasonable layout.

Any way, here are design criteria for the 2x4 block.

1. Insert key must be next to Backspace key.

2. Insert key must be in the same column as Delete key.

3. Backspace v Delete. The Backspace key must be closer to the home row and the index finger.

4. The block (Paste, Cut) must be translated image of the block (Insert, Delete).

5. The Copy key must be adjacent to the Cut key (rather than the Paste key).

6. Copy v Cut/Paste. The Copy key must be closer to the left edge of the layout.

7. Undo v Redo. The Undo key must be closer to the index finger. The Redo key must be closer to the left edge of the layout.

8. The triplet (Backspace, Insert, Delete), as opposed to the triplet (Cut, Copy, Paste), must be closer to the index finger.