On Thursday, there was much excitement when The MagPi issue 57 was released to the public. The issue came bundled with a Google AIY Projects Voice Kit, including a Voice HAT, a microphone add-on board, a big arcade button, a speaker and bits and pieces with which to put it all together. There was a big rush to get hold of the issue. Indeed, The Pi Hut, the official outlet for The MagPi, sold out within hours. It has now become very difficult to get hold of the issue anywhere!
As a subscriber, I received mine on Friday (a little irritating given that, until now, subscribers got theirs on the launch date, but anyway…) and on Saturday I was able to explore the kit.
If you’re still trying to get hold of the issue/kit, The Pi Hut tweeted today (Monday) that they had ordered another pallet-full. Visit this page and sign-up to get notified when they’re back in stock.
Hardware
The main component of the AIY Project Kit is the Voice HAT:
From a features point-of-view, this is a very exciting HAT. There are connections for the microphone add-on, the button and, of course, the speaker. However, most of the rest of the GPIO is broken out as connections for servos and other inputs & outputs. There are also specifically break-out points for I2C, UART and SPI – particularly important for sensors. There is even a place for an additional screw-terminal for a second speaker, giving stereo audio output. In short, you’ll easily be able to expand the system by adding other inputs and outputs, and I commend the designers for adding all of this great functionality.
The button is, perhaps, a bit of an overkill for this fairly simple project. It has five terminals (of which four are used) and needs to be assembled from three parts before use. It is nice and big, though, and it glows beautifully! The microphone board is ingenious – just big enough to allow stereo input, but small enough that you can just tape it to the cardboard box that makes up the project housing.
The cardboard housing is made of heavy-duty material, which means it’ll put up with you bending it the wrong way (as I inevitably did) when assembling and it protects the Pi and other components quite well. It also allows access to all the Pi’s ports, which means if you need to plug it into a monitor, you can do so easily.
You are instructed to use a Raspberry Pi 3 when assembling the project. This seems a bit over-the-top considering how much the Pi 3 costs, especially when it has been tested out as working with a Pi Zero. The housing, however, is specifically designed for the Pi 3, so you’ll probably want to use a Pi 3 anyway. However, it is reassuring to know that it works with the Pi Zero (and Pi 2 for that matter) in case you want to make the project smaller at a later date.
Software
For this project, the recommended route is to download an SD card image from the Google AIY Projects site, although you can also add the software onto an existing Raspbian install by following instructions on GitHub.
The provided image is nice because it has everything pre-installed and ready to go. It’s also smaller than the regular Raspbian image so it is a bit quicker to download and write to the SD card. Apart from the pre-installed software, and the AIY desktop background, very little is different, and this is re-assuring for those of us who will want to extend the provided software.
There is a little bit of manual configuration to do, even with the pre-installed image. I think this is actually to its benefit – you learn more this way about how to do things, such as configuring the Google API.
Assembly instructions
The instructions for assembly are available both in The MagPi and also on the AIY Projects site. The instructions come with a large number of photographs to aid your progress.
All I can say is Thank You! to whoever wrote the instructions and took the photographs. The guidance is clear and the photographs are extremely useful when trying to get things in the right orientation. I did have a little confusion when setting up the Google API. The instructions assume you have never set-up the API before. I had, so the instructions didn’t quite match what I was seeing. This is a minor thing, though.
Using it
Once assembled and plugged in, you press the button (or clap your hands if you’ve configured it to respond to this audio signal) and ask it a question. It’s as simple as that. I had success getting it to answer questions, and some of them are very witty. (Ask it how to make tea or coffee!) I liked how it didn’t just use one site to provide the answers – it made me feel that I was getting more balanced responses. I have noticed that you can’t really get it to do much – such as playing podcasts. It just didn’t seem to know what to do. However, with a little programming, I’m confident that I’ll be able to create custom actions for it to carry out. I also noticed that if you don’t provide it with a valid input, i.e. if you clap your hands and don’t say anything intelligible, it tells you so, but the audio is very distorted. Other users have reported a similar thing with locally-held sound samples, so this is clearly a bug.
Overall
For the £5.99 cost of the magazine, you get a ridiculous amount of high-quality goodies. It could have been done cheaper, perhaps with a pHAT-sized board and a lower-quality button, so I commend Google and The MagPi for the high standards they’ve stuck to. It is a pity that more were not produced, as this issue has become difficult to get hold of. Indeed, some copies have appeared on eBay for up to £100, which is disgraceful behaviour, but entirely expected!
Overall, highly recommended if you can find it. If you want the kit, but can’t find an issue, the easiest thing to do is to subscribe to the MagPi. Alternatively, sign up to this Google Form to be informed when the kit becomes available to buy.