2017 has been the year of dubious TV comebacks. Take the Crystal Maze; for all his charms, Richard Ayoade is no Richard O’Brien and the 2017 version never hit the heights of its 90s predecessors and who really wants to see Blind Date back on our screens? Some things have had their time and are better left in the past. Thankfully there was a more welcome return in 2016 – Robot Wars. Why it ever went away in the first place is a mystery, but the ‘maker’ culture and the growth in bedroom computing brought about by affordable computers such as the Raspberry Pi has cleared the ground for a new generation of robot builders and inventors.
Today’s Robot Wars competitors weigh in at around 110kg and can be anything up to 2m in length. However, these are more modest robots around, but which have a similar purpose – to enthuse and inspire children into pursuing their own ambitions in STEM. The protagonists in this particular battle weigh in at a rather more modest combined 55g – that’s 46g for the Sphero Mini and a featherweight 9g for the Ozobot Bit. This post will evaluate the merits of both these devices and compare them to each other, with a leaning towards their educational potential.
Both these devices have a feeling of quality about them, possibly more so the Sphero, though this could be down to its extra weight from the gyroscopic features. I’ve not seen the packaging for the Ozobo
t other than online (I am trialling it on behalf of Computing At School) but from what I can see it looks and feels like you would expect for a £50+ gadget.
The Spehro’s packaging is a thing of beauty, with the ball sitting proudly in its perspex box and the peripherals tucked neatly below. Once in us, the lower half of the perspex box makes a useful stand; without it you would run the risk of it rolling of a table or desk. The Ozobot comes with a set of cards which the robot can follow, whilst the Sphero has a set of cones and bowling pins which you can have fun with whilst you master the basic controls. Having not seen the Ozobot’s packaging I won’t call which is better, but I can say I was very impressed with the Sphero.
I’ll call it a score draw.
Sphero Mini 1 – 1 Ozobot Bit
Both devices are charged via a micro USB charger. The Ozobot’s is exposed, so therefore very easy to locate, whilst the Sphero’s is found by removing the outer case. Whilst this is not much of an inconvenience, if you were dealing with a class set, it would make the charging process a bit more laborious. The flip side is that it means when it’s in operation there’s nothing to interfere with its shape and clean lines. To get up an running with the Ozobot you simply need to power it on, calibrate it and pop it onto one of the supplied templates and you’re away. From there you can quickly experiment with your own designs – all you need is a piece of paper and a thick felt tip pen. There is slightly more to setting up the Sphero Mini. You need the Sphero Mini app (IOS, Android) to pair with your device via bluetooth, then as with the Ozobot there’s a quick calibration activity which you complete on your tablet or phone – once that’s complete you can control your robot remotely in a variety of ways, more of that later.
For it’s ease of charging and simple out of the box operation this is a narrow win for the Ozobot.
Sphero Mini 1 – 2 Ozobot Bit
Controlling your Robot
There are many similarities between the Mini and the Bit, but this isn’t one of them – these two devices are controlled in very different ways. The Mini is more conventional in that it relies on an app based interface via bluetooth. The app enables you to control it with a joystick type interface or by facial movements and expressions. Both are good fun and you get immediate results, just be careful you have accurately calibrated it, otherwise it will disappear in all sorts of random directions. The cones and skittles provided in the box are a neat way for you to practice finer control of your robot. The Bit is controlled via a colour sensor on the base of the robot which enables it to follow lines on a page or a screen. You can control it by adding colour combinations to the lines to perform actions relating to speed or direction. With this it is possible to program the Bit almost immediately without having to understand any technology or programming interface. With that in mind, for its practical programming potential, it’s another narrow win for the Ozobot.
Sphero Mini 1 – 3 Ozobot Bit
Usability (including apps)
There are a number of apps to support both these devices. The Mini is compatible with two Spehro apps – Sphero Mini (IOS, Android) and Sphero Edu (IOS, Android, Kindle, Chrome). Most will start with the Sphero Mini app. With this you can control your robot in a number of ways. Most will use either the joystick or the tilt functions. With both of these it’s not especially easy tp keep close control which tends to result in it regularly disappearing under tables and sofas. There’s also a slingshot mode which is good fun with the skittles – make sure you do it with a solid object behind them! Finally there’s the face mode – this is great fun and worked straightaway for me. The novelty wears off fairly quickly, but it would be good fun for younger children. There’s also three games which you can play, controlling them by holding the Mini in your hand and rotating it to move your character. This is a great feature and demonstrates the connection between the robot and the tablet very effectively.
The Sphero Edu app turns the Mini into a programmable device with a block based Java Script interface. It’s very accessible and easy to use to anyone new to coding or for anyone familiar with similar interfaces such as Scratch. There’s lots of scope for using this in the classroom, and a great way to develop physical computing beyond traditional floor bots.
I have not yet experienced any problems with the bluetooth connectivity, although with a set that may become an issue. In terms of charging, as mentioned previously the outer skin needs to be removed. Sphero advertise a 1 hour charge time, and 45 minutes usage – the former seems to be accurate. I have not tested it for 45 minutes, however when it’s been used briefly and then left, any remaining charge seems to trickle away quite quickly. You would definitely need to plan to charge these before any lesson.
The Ozobot also has a couple of core apps – the main Ozobot App and Ozogroove Bit (both IOS, Android), there is also Ozoblockly, which is the block based programming interface. This looks very similar to mBlocky and has obvious similarities with Scratch. Without the bluetooth connectivity of the Sphero, the Ozobot relies on a direct connection between the robot and the app. This is easy to achieve on a tablet – simply lay it on a flat surface and pop the Ozobot on the screen. It then picks up instructions using its colour sensor, and reacts accordingly. If you’re using Ozoblocky this involves holding the robot against the screen. This is a very different way of programming a robot which removes the need to communicate via what can be troublesome bluetooth. My experience has been mixed. The Bit doesn’t always pick up the light sequences first time, and I found the challenge mode on the Ozobot app frustrating. It frequently asked for the Ozobot to recalibrated, and even then often didn’t follow the expected path. When you complete a challenge, the inability of the robot to communicate back to the tablet means that nothing happens to signify you’ve succeeded. I can see this being a big problem in school. The range of things you can get an Ozobot to do is great, but if they’re not doing what you expect, the learning opportunities will quickly recede. Ozobot are marketing class sets of the Bits, but from my experience it would be very difficult to manage a whole class with the issues I’ve faced. More generally, I have found the apps to be clumsy and difficult navigate around.
It’s better when run on paper with hand drawn lines, though they need to be just the right thickness. I think this has more potential than using with the app. It removes the level of complexity the apps add, and gives the user a more direct connection between their instructions and the actions of the robot.
The Ozobot is easy to charge, and does so fully in about 45 minutes and functions for 90 minutes. This is about twice the time the Mini will run for, probably due to its lower mass and slower motor.
In terms of usability, it’s a clear win for the Sphero. The apps are also better designed and more user friendly which brings it back to parity with the Ozobot.
Sphero Mini 3 – 3 Ozobot Bit
In terms of their potential as devices to facilitate learning, there’s not much to choose between them. The coding interfaces is where there is most potential, and both offer an accessible easy to use interface, but deliver the code in different ways. The ability to program away from technology is a key differentiator for the Ozobot, however this is offset by it’s sensitivity, and the need to frequently recallibrate.
Both Sphero and Ozobot have gone to great lengths to embrace the educational potential of their products. There are loads of freely available resources for both devices on the respective website. They each adopt a slight different model – Ozobot have a certified educator programme, whilst Sphero opt for a more open community. Personally, I prefer the Sphero model as it encourages more creativity and a greater breadth of resources.
Having not yet used either in lessons (I only have one of each) I will score this off the potential I can see in each device. The programming interfaces are as good as each other, but based on the more open community and better usability, it’s another, and this time decisive win for the Sphero Mini.
Sphero Mini 4 – 3 Ozobot Bit
These are both great devices, which bring physical computing within reach for far more than was possible even only a couple of years ago and for that they should be applauded. They both have their merits, and have clearly been designed with education in mind – they are more than toys.
The Sphero Mini wins narrowly for me, based mainly on its better usability. This may well be a personal thing, others may prefer the on screen programming of the Ozobot to what can be (though not in my experience) the troublesome bluetooth of the Sphero.
If you are looking for a new way to get into physical computing, I would suggest you give both these devices a go – I’d be interested to find out how you get on.
I hope that this generation of affordable robots will inspire a new generation of roboteers, and ensure that this time, the mighty Robot Wars is back for good…