Setup for failure

Tamapotchi note #2

One of the aims of our Tamapotchi project is to cover as much aspects of product development as we possibly can. All three of us have been part of these kind of projects professionally over the past 10–15 years, but we were never in control of every aspect of the development process. At times that can be frustrating; especially when important design decisions are taken by someone else than us, the designers. Of course we know why this is and fully accept it as part of our roles, but that doesn’t stop the itch.

Covering all aspects means that we need to do things that are relatively new to us. One of these things is hardware; we conceptualised a pretty working prototype of a smart pot that helps keeping plants in a pristine condition, but actually we have no idea how to build that. Yet.

We need sensors, that we do know. Although I’ve never managed to keep a plant alive for more than a month myself, even I know that light and temperature conditions, combined with a certain soil moisture level are essential to its survival. But what do we attach these sensors to? Well, even that question we could partially answer ourselves, because we’ve heard collegues raving about Arduino’s and Raspberry Pi’s for years. If only we had paid a bit more attention to what they were actually saying.

A few minutes of Google and I already knew that a Raspberry Pi would be a too heavyweight hardware solution for our project; those are really small computers running a full operating system. The microcontroller boards of the Arduino platform seemed to be a more appropriate and affordable option. And hey, there is a lot that can be found online about Arduinos. An awful, awful lot.

So I decided to consult two of my raving colleagues first. The first pointed out that we should be looking for a low-energy solution; we wanted a wireless pot and changing or recharging batteries should be reduced to a minimum. Using WiFi to transfer the sensor data would drain the batteries soon, so he advised to use either Bluetooth Low Energy (BLE or Bluetooth Smart) or ZigBee. Another colleague even sketched the preferred hardware lineup. He advised to hook up one Arduino board to the internet with an ethernet or WiFi shield, and use an XBee to communicate with the pot. The pot had another, small Arduino board (FIO), also fitted with an XBee for communicating the sensor readings to the central Arduino board, that would in its turn send the data to a cloud service.

That setup sounded about right for out Tamapotchi project. The Arduino FIO has an onboard XBee socket, so I didn’t need to attach an extra ‘breakout board’. Still, the FIO, although a lot smaller than an UNO, was quite large compared to some other boards. And the setup contained a lot of parts. I figured that every link between parts poses a risk of failure for rookies like us, so I should keep the amount of parts limited to the minimum. Even if that means we have a less-than-optimal hardware setup.

So I graciously dove into the luring ocean of online resources covering Arduino (or comparible) boards and components. And instantly drowned. I don’t know the first thing about electricity, let alone electronics. I think I remember spending some time during physics class drawing circuit layouts when the topic of electricity was covered. My circuits definitely looked best, but never worked. I think that was about the same time I decided to apply for art school.

It took me some time reading the online Arduino resources, especially the excellent, to realise that besides Arduino boards, there are countless other manufacturers that create and sell boards that are based on the same open platform. Great. Like the list of Arduino boards wasn’t long enough already. But it turned out there are more people like me, asking rookie questions on online forums. And lots of inspiring videos on YouTube showcasing projects people did with specific hardware setups.

I ended up with two viable options. The first was the Blend Micro board from RedBearLab, which has onboard BLE, low energy consumption and has a small footprint, but is large enough to be handled by someone inexperienced as me. And it is an ‘Arduino at heart’, as Arduino calls it on their website. Sounds reliable. The second option was the XBee Wifi Cloud Kit, which actually has all components we need in our project already prepacked, preconfigured and ready to roll. It even included a cloud service to process, store and expose data. The website promised even I would be up and running in minutes.

The choice was not hard; we don’t want to be up and running in minutes. We want to learn and that includes failing, or at least creating enough chance for failure. We could build the prototype with the XBee Kit and still have no clue of what we actually did. We don’t know how to hook up the Blend Micro to sensors and the internet. Yet. But we will find out trying, frying an occasional development board as we go.

(The picture at the top of the page shows some of Patrick’s first sketches for the Tamapotchi app characters.)