The ESP8266 Shows Up in These Amazing, Extended Interface Smartwatch Prototypes From IML Dresden!

The ESP8266 was, and still is, a popular choice for a one-stop shop solution to your embedded projects needs.

While it doesn't sport the beefy 32-bit processor of its ESP32 sibling, its 160MHz core, WiFi capabilities and oodles of peripherals make it a very capable workhorse that has been the backbone of many a project.

So it's no surprise to see it being put to great use in this set of future smartwatch technology demonstrators, coming out of IMLD - Interactive Media Lab Dresden, with its Watch+Strap project.

This is some interesting looking work, with some solid effort behind it — they have developed working hardware prototypes, complete with a functional software solution that demonstrates the enhanced user interaction experience made possible by an extended display area.

This is a huge step beyond the non-functional mock-ups and vapor-ware renders that often taunt us from the Internet. The engineers have done their homework, and then some!

It looks like the team behind Watch+Strap have spent a fair bit of time thinking about this project, as they've developed not one, but two functional prototypes of their Watch+Strap platform, with a third in the works!

A strapping example of user interaction

Watch+Strap aims to extend the interaction surface of the typical smartwatch onto the wristband, opening up a great deal of potential user interaction opportunities. There's a few potential use cases shown below — I'm especially fond of the map route suggested in E!

They've done this by utilizing the recent development and market availability of flexible display technology.

A few years back, SparkFun started selling this awesome flexible OLED display, and since then, there has been a bevvy of modules available for those who know where to look.

Envisioned for this very application, the trend has caught on, and we can now buy flexible EPD (electrophoretic display) and OLED (organic light emitting diode) panels from our favorite suppliers. What is more important for us hardware hackers is that now, prices aren't enough to make us wheeze! This flexible EPD below? That's somewhere around $15!

It's hard to belive that things like this flexible OLED panel, shown below, are now on the consumer market as standalone products, and not restricted to the premium tier manufacturers — despite maybe retaining their premium price tag (for now).

A flexible display, and a flexible hardware platform

The team have sensibly picked an existing smartwatch to leverage as a central platform. The Samsung S2 that they chose is a popular choice among hardware hackers — it's a decent platform to base off, and offers a crisp OLED display for the "focus" area of the user interaction.

In addition to this, the casing is very solid, and has heavy duty wrist strap mountings. A blessing not only for for the one on my wrist and my clumsy nature, but also ideal for mounting these slightly chunky, "prototype-level" wristbands too!

But, you're here for the aftermarket parts, and I hear you - let's cut to it!

The first demonstrator the team has built is based around the Waveshare 2.13" EPD panel, shown further up in this article. It is slotted into a custom 3D-printed wristband, along with some force sensitive resistors, allowing the user to swipe through the display!

The eagle-eyed will have spotted the ESP-12F based EPD driver board from Waveshare, and the housing required to mount it.

There's little sense worrying in optimizing the display hardware ate this point, it will always be possible to get that small enough at a later date!

The second hardware demonstrator is a little more physically streamlined, but we can still pick out the individual parts with relative ease!

See item 1 n the photo below. Does that FPC cable sneaking out the bottom of that wide-aspect ratio display look familiar? That'sright, it's the very same flexible OLED panel that SparkFun have listed — and I'm showing my absolute geekiness here when I say I recognize that as the SparkX variant — SparkX being the SparkFun skunk-labs!

It's a little harder to make out the MCU here, but I think I can see a Weemos D1 and it's LiPo charger block poking out from under call-out numbers 5 and 4, respectively!

Hardware revision 3, although still a concept at the time of writing, is looking to leverage the HD, flexible OLED panels that are still not quite commercially market ready.

Perhaps due to cost and also I imagine, due in part to the robustness of the current panel technology, the team has prototyped the HD part of their software by mounting the watch strap over a tablet PC, for the purposes of the demonstration. The potential is clear, however!

Given the troubles even Samsung et al are having in bringing us our long awaited folding devices, there's still a bit of work to do before these OLED displays are ready to take the abuse we consumers throw at them.

While they wait those wider issues to be sorted out by the panel manufacturers, the team have are focused on evolving their software (soon to be released on GitHub), and optimizing the hardware further, perhaps soon starting to look towards a more bespoke controller?

Where to from here?

I'd advise taking a look through their technology paper here, and of course, paying a visit to the IMLD project page.

I'd love to see some home-brew implementations of these interfaces from the Hackster community, and with all the source parts so easily available, I'm hopeful some people will give it a go!