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Product Management. Hands On Consulting.

Digital interface for hardware changes the rules of the game

Updated: Jun 13


PM for the Physical World Series: Part III


Important disclaimer:

All charts shown are for illustration purposes only, and do not represent factual data or research. They were generate via prompting GPT4.0 with the open questions in the titles, and were then developed via dialog with the LLM.


Human machine interface - a historic journey

Dials and Gauges

Remember that in their pure functional form, many products do not require human interface at all. Let's call this "Interface Generation 0"

19th century bicycle. What interface does it need?
19th century bicycle. What interface does it need?

But then again, other products must have some kind of safety indicators: Left unattended, kettles would burn, Steam pipes could burst, and emptied fuel tank could stall your car - or worse. Enter Generation 1 interfaces, providing critical information to the operator, so they can adjust inputs to control critical processes.

The analogue devices that were developed to that purpose were dials and gauges

Thermometer - you're still in the safe zone
Thermometer - you're still in the safe zone


Digital interface for hardware changes it usage patterns

Something happened in the two centuries passed since dials were introduced: The information age stormed into our lives, with some of its initial manifestation: Digital interfaces, which I'll refer to as Generation 2 interfaces: Digital interfaces - hard coded and programmed, driven by integrated circuits:

While early generations of these displays were built using LED arrays, the next generation used Liquid Crystal Displays. Each contiguous area is a single segment, wired to one of the IC IO ports.

Liquid Crystal Display - much more flexible
Liquid Crystal Display - much more flexible

You'll notice the graphic flexibility enabled in this 7 segment like display, although the size variations, and some lettering suggest that there is more at play than rigid diodes.


In the next example, a lot more artistic freedom is allowed, showing the limitation is in the IO count of the driving board.

I have made several of those: as free-form as they look, the initial setup took notes from chip lithography, and is quite rigid: Once you have the vector graphics, it is converted into a mask, and several weeks later, the prototype is ready (while you feverishly prepare the low code driver). Any error or change sends you back to the initial point.


The need to flexibility in design resulted in the dot matrix display, where a sophisticated IC driver control a lattice of columns and rows to lighten dots: A 100 by 10 matrix provides 1,000 pixels, but requires only 110.

Dot matrix LCD
Dot matrix LCD

And as the industry progressed, higher refresh rates, higher pixel counts, and the introduction of color (let alone the introduction of sound) culminated in the displays we have come to accept as the standard.

Nintendo Gameboy: Color dot matrix and rich sound
Nintendo Gameboy: Color dot matrix and rich sound

A whole world of gaming, but also interface conventions, grew out of this platform.


Touch! and more

As touch interface came in, physical buttons, with their rigid placement and behavior, gave way to software defined interface.

Designers can place buttons and model complex interactions almost regardless of physical limitations, focusing instead on ergonomics and cognitive human factors, and - even more importantly, with the ability to iterate furiously.

The touch feature is just another layer
The touch feature is just another layer

The initial paradigm stems from PC graphical interface (using single touch mouse click and drag). Soon enough, however, multi touch gestures, such as pinch, spread, and rotate, evolved, as single touch gestures evolved, to create a rich interactive environment.


On Air!

This section should be named: "How I Learned to Stop Worrying and Love recalls". Those of you in the manufacturing domain know how dearly recalls cost: The loss of face, the cost of shipping back and forth, the possibility of sending a technician to mount a pole 5 hours drive from the nearest airport, just to update some firmware... Could all this be gone?... 🥹

Enters FOTA (Firmware Over The Air), with pioneers such as Red Bend (acquired by Harman International) and provided the magic capability of downloading a new version of an operating software, and rebooting safely to the new version without losing data.

Ubiquitous today, for any smart phone, it was revolutionary at the time. It is still a game changer today, with players such as Tesla, totally disrupting the mobility world with its electric drive train, but also with its magic-like overnight upgrades:

Tesla: Overnight firmware update - for your car
Tesla: Overnight firmware update - for your car

If you are a Tesla owner, you could have find one morning, that the range has increased by a 100Km, or that 0 to 100Kph was cut by more than 50%, in steps called "Insane" and "Ludicrous" modes.

While 0 to 100Kph is a car-nut thing (can't use "petrol head" for an electric car, sorry about that), the effective range of eCars is a huge pain point.

Another user delighting feature was when, one Christmas eve Tesla owners found their heating system turned into a virtual fireplace:

I mean, these are very effective differentiating features, and traditional car manufacturers just cannot cope with such ferocious tactics.

As a matter of fact, digital interfaces are perceived today as the most differentiating factor for cars. Consider this, though: Ford Model T and today's most flashy cars perform a very similar task: Allow a driver transport themslves and their passengers as fast, and as agreeably as possible.

But in the nearing future where driving will be a thing of the past - what is a car, if not a smartphone on wheels?



The last frontier is the fusion of multi-modal input methods, some explicit and others which do not require user action, into the interface of hardware products: Accelerometers, heartbeat, temperature, visible and hyper-spectral imaging sensors (I mean, cameras), as well as sound sensors are all now integrated, allowing advanced functionality.

Inputs are by no means the end of it, as communication protocols supported by our devices proliferate for data transfer, monitoring, and activation. Digital interface for hardware takes center stage offering new user interaction, creating new value.

NFC - Near Field Communication - used for activation
NFC - Near Field Communication - used for activation



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