If you want to cut to the chase, at about 22 minutes in the robot starts moving – much to the surprise of my dog Ellie.
I really liked the Monk Makes RFID Clever Card Kit, so I was delighted when they invited me to review another of their products. The Raspberry Pi Robot Rover kit was an obvious choice as – oddly – I’ve never done any robotics with any of my many Raspberry Pis, and I know this could be a great way to engage young minds.
It currently sells for just under £40 for which you get two pretty tough motors, a tough clear plastic chassis, lots of nuts and bolts, two chunky wheels, a wifi dongle, screwdrivers, battery holder, an ultrasonic distance measuring device – and Monk Makes’ own board which sits on top of a Raspberry Pi’s GPIO pins to control LEDs, the motors and which can also take sensor inputs from switches and the distance sensor.
It took me a couple of hours to assemble the kit – bear in mind I was filming the process which made it much slower. Children would need adult help as some of the steps are quite fiddly, such as bolting the Pi to the chassis and connecting the motors and battery pack to the board requires careful concentration to get the polarities right. Assembly is explained in videos on the Monk Makes web site, though I’d really like to see some written assembly instructions too.
It comes with some sample Python programs. The first ones are projects involving the ‘squid’ button and LED, including a really impressive one where you control the colour of the light by sending tweets. I’m not sure what these have to do with the robot kit, however and I wonder what they are doing in the kit and the manual – perhaps this could be an appendix?
The bespoke board to control the robot is brimming with pins and makes connecting sensors and switches very easy. It’s great to see that the GPIO pins are all carried through, so unlike with many HATs which block off other pins you might still want to use in a project. I suspect this neat little board has many potential uses beyond making a simple robot – anything that needs sensors, switches and requires motors to be powered and controlled in software.
I very much like the way that the robot can be powered from batteries AND the Pi’s USB power supply at the same time, a very good idea for testing and building. If your 6 AA batteries have enough juice you can then disconnect the USB supply and send your robot off into the world on its own.
The programs to control the robot worked well – you can SSH into the robot’s Pi and then control it using arrow keys on another computer. By far the most enjoyable project, however, is the ‘Rover Robot’ program. This sends your robot off exploring its environment and avoiding obstacles using the distance sensor. It worked very well indeed and was great fun to watch.
I’d like to see some explanation of how the core robot Python code works in the manual – I had a quick peek inside and it looked a little opaque, so some more information on how to write your own code to control the robot.
This kit is a good introduction to Raspberry Pi robotics, with plenty of scope for extension activities and I look forward to seeing future iterations of this device and more products from the inventive folk at Monk Makes.