We’re very excited about this one. For a long time, any other Raspberry Pi robot has seemed to pale in comparison with anything put together by the PiBorg team. It’s never really been a fair comparison, of course; a lot of Pi robots are made for those on a budget, and so focus on making a first foray into robotics inexpensive. Not all the PiBorg robots are kits to begin with, so when the monstrous DoodleBorg is racing around in videos, it’s a wonderful spectacle, but not many people are actually going to be able to build it.
The main kit that PiBorg usually sells is the DiddyBorg, a six-wheeled robot retailing at around £200 that's a very serious bit of kit compared with the budget ones. It’s still expensive in comparison, which is seemingly where the 4Borg robot kit comes in. Introduced as ‘DiddyBorg’s smaller brother’, the 4Borg is a four-wheeled robot that strips the PiBorg design ethos down to its essentials: four motors, four wheels, a motorboard to control them, and a metal chassis to hold it all together. It’s powered by Raspberry Pi and even comes with a rechargeable battery pack like the kind you’d find in an RC car.
Simple but sturdy
On the surface, then, it does seem like a simple robot – no sensors are included, although there's a mount for a Pi Camera Module in the front of the chassis. Automation for the moment is therefore limited to timed motor bursts, although with a bit of work you should be able to add in some motion and face detection using a camera.
Building it is a joy. The best and possibly most clichéd way to describe it is like a toy for grown-ups. The chassis comes as a thin sheet of pre-cut metal that you need to bend into place to fit together, like a cardboard model. It’s extremely sturdy and all the supplied parts feel like they’re good-quality gear (because they are). You can spend a few pounds more when buying it to have the motors and an on/off switch pre-soldered; they’re definitely not difficult soldering jobs, but if you’re still a complete soldering novice it’s a small price to pay for confidence in your materials.
As you can see from the images, the Raspberry Pi and motorboard are mounted on top, leaving the insides of the chassis fairly hollow, save for the ends of the motor and a small slot for the battery. Due to this and its metallic body, you could definitely upgrade the robot down the line by mounting line sensors, or affixing custom brackets for an ultrasonic sensor. Adding them via code shouldn’t be too difficult with a bit of research.
Speaking of code, once complete, you can begin using it pretty much straight away after construction. Code examples are available in the resources for the 4Borg online and just require a little setup on the Raspberry Pi before getting them to work; the examples are downloaded and installed during this setup phase, so you don’t need to add them manually.
The robot is programmed in Python, making it very compatible with the Raspberry Pi. Instead of using GPIO Zero, it mainly uses its own library called PicoBorgRev. This is for the PicoBorg Reverse, the motorboard controlling the robot. The code examples are quite elaborate, showing off how to perform an automated drive or how to control it via a connected joypad - specifically, a PlayStation 3 controller. You can get a good feel for how you can manipulate the code by studying it. There are a few basic commands, such as driveLeft and driveRight, that control the power going to the left or right motors respectively; you can only control each side rather than each motor with the 4Borg setup. It’s a touch more complicated than some other cheaper kits, but the 4Borg is a touch more advanced than those kits anyway.
Honestly, the 4Borg is everything we expected. For £99 you’re getting a proper PiBorg robot, with the inherent quality that goes with that. It may start off a little simple, but there’s plenty of room to grow with this as the platform, or even go bigger and better with another chassis and kit. With a new Robot Wars around the corner, maybe this could be your entrance to a wider world of robots…
Last word
5/5
A quality piece of kit, just what you’d expect from PiBorg, and a fantastic jumping off point for people who really want to learn about robotics and computerised vehicles.
