Abandoned idea: Motorized potentiometer

In old good days, the volume of TV / radio / amplifier was a potentiometer (rotary variable resistor). Remote controls already existed back then. How did a remote control move the volume? By combining a motor to the potentiometer:

Now motorized potentiometers can be found in exotic MIDI controllers.

I have seen rotary encoders on many enthusiast-grade keyboards. I am afraid that I feel they lack appeal. Without dedicated software running on PC, there are few good uses. Moreover, the rotary encoders are always incremental type. That is to say, the knob orientation itself is irrelevant. I feel something essential is missing.

If dedicated software is unavoidable (such software is hard to maintain), why not motorize? It is not only an input device, but also an output device. I feel the interactivity is wonderful. Of course, it makes the knob orientation relevant. So I investigated the area a bit.

The showstopper #1: Short life

The life of potentiometers is typically 1,000 to 30,000 cycles. Motorized products claim around 10,000 typically. It is good performance as the volume of amplifiers. For TVs, it looks uncertain. For MIDI controllers, I feel much more uncertain. Many MIDI controllers feature motorised faders (linear variable resistors), and many people complain that motorised faders don’t last very long. The replacement repair of the component looks almost mandatory.

Rotary encoders have a much longer life because it has no sliding contact. Why not go motorized rotary encoder, absolute type? Because no one makes it. I hope it will be released someday.

The showstopper #2: Too bulky

This drawing shows the dimensions of a motorized potentiometer:

The dimensions are typical. It says that the keyboard should be thicker than 50.5 mm. I am too young to see such thick keyboards. Even if I place it on the enclosure's side, the height is 29.5 mm. Too bulky.

Motorized potentiometers and faders are fancy, but it is hard to bring the valuable product to life.

How to make an exotic keyboard

If you have an exotic goal, you will go to somewhere exotic. If not, you will stay in a comfortable, familiar place.

The most non-exotic, comfortable, familiar goal is, for sure, money. As far as your goal is money, your product never become exotic, and you wouldn't care about that because you just want to give your product an exotic look. We are very familiar with such fake products. Good luck.

Typing speed competition is an exotic goal. But I think it is a bad bet. Typing speed depends heavily on adaptation. It is inevitable that your product will end up resembling laptop keyboards. In other words, buy the Apple Magic Keyboard.

On the contrary, industrial special-purpose is a promised bet. The photo below was taken in 1970. Look at the left bottom. This is an industrial special-purpose keyboard (The keyboard is for CAD).

BTW in Japan, the descendant of the keyboard was alive until 2024. The final model was USB:

This is a promised bet, but... Such a chance is rare. Nowadays touchscreens make it more rare.

I mentioned about adaptation above. In the first place, why are we so used to laptop keyboards? The answer is the ecosystem. Sometimes we can choose programming languages. Each of programming languages has its own ecosystem, i.e. CPAN or PyPI. Sometimes no choice. C is the only option in many cases. Hardware is much more no choice because it is bound to physics. We cannot make vacuum compressed physical keyboards! (There is an exception.) Moreover, volume efficiency matters. Many exotic programming languages are free because we don't need expensive molds for copying their toolset. About exotic keyboards, for example, I paid more than 10,000 USD for the molds for Nanaju, therefore its unit price is 600 USD. You can get free 3D model of Nanaju under MIT license because we don't need expensive molds for copying a Blender file. In the ecosystem, namely in the kingdoms of Apple or Microsoft, no one cares just 10,000 USD of mold cost because their production volume is a figure in the millions. Thus we have no choice, thus we don't call the ecosystem "the ecosystem", just buy Macbook or Surface, and adapt to them.

BTW the vacuum compressed physical keyboard:

Now we are ready to imagine a Copernican revolution. Making a miniature ecosystem, just like a miniature garden! We cannot live in the miniature ecosystem, but it makes possible to materialize radically exotic things. The computer architecture, the paradigm of toolset, the usage of screens, etc, etc. Niklaus Wirth made it as an academic study, Project Oberon. This is another promised bet and doesn't require a rare chance.

As you know, this, too, is not the way of Nanaju.

I am a revolutionist. A revolution is not a story about transfer of power. An Afghan said that "A goat stands up and a water buffalo sits down." No, this is not a revolution. Gaining a different perspective on what rules over us, this is a revolution. Karl Marx wrote a ton about the capitalism and little about the communism. He never made a miniature garden.

The goal of Nanaju is our living.

Please remember the first 60% PC keyboard in the history, Macintosh 128K M0110. Why was it made so small? Because the desk area is finite and the users were only supposed to use the Mac for a small amount of desk work. This concern is even more significant today. This is the goal of Nanaju too.

So far, this goal doesn't seem all that exotic. Now the twist comes in: Coordinating with the software ecosystem, but ignoring everything else (as far as possible). To ignore the hardware ecosystem, I made original 17 mm pitch PBT keycaps. It ignores our adaptation too.

Nanaju is a living criticism to the ecosystem. Our adaptation is also a part of the ecosystem. We cannot deny our adaptation because it is just a fact. Power transforms facts into oughtness. Yes, the price tag of a mass-produced product is power. So do you always buy the cheapest product?

I wrote above that “we have no choice.” Now we have Nanaju. If we start to call the ecosystem "the ecosystem", if we gain a different perspective on what rules over us, it is a revolution.

The layout of Nanaju

This is the layout of Nanaju: 

I saw several keyboard layouts developed with the "waterfall model" style. Each of those layouts was derived from a set of principles. For example, "Bigrams should not be typed with adjacent fingers" is one of such principles of Dvorak keyboard. Sadly this principle is wrong after electronic typewriters. The principle is correct if the typewriter inhibits key rollover mechanically. Now we cannot live without diodes for good key rollover.

Many of Dvorak keyboard principles are still relevant today. But the set of principles is not. The set was short-lived compared to humans. Moreover I have seen some absurd principles in other places. Dvorak keyboard doesn't have such absurd principles and this is why it has been successful comapred to its rivals. But how can we avoid contamination of absurd principles? Just by testing in the real world, no other way. I already tried it in Japanese kana layout. My thoughts: It is a good way to find flaws in the set of principles, not to find a fruitful result. I am very skeptical about the effort to find the "best" layout from a set of principles.

I did not try to find the "best" layout for Nanaju. Instead of the best derived from something untested, I pursued something tested by making/testing many, more than ten prototypes in the haphazard way on a patchwork basis. I pushed myself until I groaned "Enough, it's enough. I did my best. I don't believe anymore that the next prototype may be fruitful. I already have spent enough energy for making/testing prototypes". Of course, the next prototype can hit a jackpot. I cannot prove the inexistence or unreachability of a jackpot because I don't have any methodology. I don't care. I am not an academic nor a sales pitch writer.

So I can tell you why N-th prototype layout isn't as good as the final product Nanaju layout, but I cannot tell you why the arrow keys are there. If I had to say, I was burned out before finding better places for them.

Although I believe that I have found some rules.

Rule one: You should not place navigation keys (arrows, PageUp/Down, Home, and End) on left and right hand both. To select text, it’s common action to input Shift + End first and then Shift + arrow. It occurs while selecting from the cursor to the end of the line except the period, for example. If you place arrow keys on the right hand and Home / End keys on the left hand, in many cases, the layout will force you to release Shift key after Shift + End. Why? At the moment, you will be pressing Shift key for Shift + End by right hand and feel difficult to keep pressing it for Shift + arrow because the arrow key is on the same right hand. This is cumbersome and occurs quite often.

Rule two: The sharp corners (Esc, Del, Win, PageUp, and Backspace) are not good places for typing because it is distant. But they are good places for hitting because they have wider margin than usual places. In typing, you type a series of letter keystrokes without waiting for feedback. In hitting, you may hit the key repeatedly without waiting for feedback, but the action is separated from a series of letter keystrokes by waiting for feedback. The separation makes the distance unnoticeable.

About patchwork, look at the Del key. It came from the RUB OUT key of the Space-cadet keyboard. There are quite a lot of layouts which have centered Shift key. "英数" and "かな" keys are stolen from Microsoft Surface Japanese version (They are irrelevant keys for English. Please remap by Vial). In this area, the stories about abandoned ideas will be much more valuable than adopted ideas, but they are long long stories...

My desktop now

My desktop now. The wrist rest is a stand-in. The real thing is too dirty.

The black dongle is a secutiry key of Yubico. The yellow round area is a finger touch detector. The secutiry key makes me free from the master password of Bitwarden.

Shipping to the US resumed

 Now I finally have resumed shipping to the US!

Changing the subject, this is the keypad rubber of Nanaju:

You may have seen the keypad rubbers of remote controls. Common remote controls use black conductive paint for their switches. But the Nanaju keypad uses metal dome switches. So the keypad rubber don't have black conductive paint.

Conductive paint switch is quite cheap but lacks tactile sensation. Not very durable too. Nanaju keypad has ALPSALPINE SKRRAAE010 as its metal dome switch. ALPSALPINE claims 5,000,000 cycles of operating life.

P2PPCB Compoer F360 Updated (May 2026)

 20260530-v0.2.6:

• Announcement: P2PPCB platform will be abandoned in Jan 2027 if there is no demand.

Now I finished the design work of Nanaju. I no longer need P2PPCB platform. If no one wants to pay for P2PPCB platform, it is not maintainable anymore.

PC keyboard Nanaju is now on sale

 

PC Keyboard Nanaju by DecentKeyboards on Sketchfab

Now it is on sale. Etsy

ESD test

 I have heard a lot of complaints about ESD damages on keyboards. Today TVS diodes work excellently, so we do not hear such complaints nowadays. But ESD is still a severe threat for the product quality. I tested Nanaju prototype by IEC 61000-4-2:2008 standard.

The result is, it passed for level 3 (contact discharge: 6 kV, air discharge: 8 kV), and failed for level 4 in air discharge (15 kV).

I will analyze the failure mode, but I think that the ESD immunity of Nanaju will not become much better. The design does not allow bigger / more components nor larger track gap. Nanaju will not be super tolerant to ESD, sorry.

Corrugated box and cushion

I am working on packing material now. End-user products require packing material. Without dedicated packing material, the shipping cost becomes expensive, and the product can be damaged on its way.