An Atmega328 standalone with built-in H Bridge, user controlled buttons and leds, home made with scrap and recycled materials.
Belterrino V3 (below) is an interesting home made stand-alone ATmega328 Arduino board in itself: built-in H Bridge for controlling motors, simple user interface with internal buttons and leds, a connector for easily plugging in a Bluetooth module, mounted on a board painted with tar pit-based enamel.
But its story can't be undestood without referring to the previous iterations, starting at the low cost autonomous robot that inspired the creation of its first version:
Great hacks happen, as the saying goes, when an itch appears on someone that is able to scratch it in interesting ways, and that's what happened when maker Ronilson Santos started to develop his low cost autonomous robot with recycled material.
When the robot was working, he noticed that the control board (an stand alone ATmega328 Arduino) on top of it was not in the same home made mood, and so the first iteration of the Belterrino was born: made on a corrugated paper card (just like Paperduino), it was a stand alone Arduino board with built-in H-bridge circuit, purposely built to run an autonomous robot.
Pictured above are both the robot, named AC.Belterra (still running the pre-Belterrino board), and the first Belterrino. The names are homages to Belterra, Ronilson's home city in northern Brazil.
Good becomes better: iterations bring new features to the Belterrino family.
Made in 2014, the first Belterrino is still in use as the brain of the AC.Belterra bot, but Ronilson thinks as an startup1 should: he didn't stop iterating. Belterrino V2 was born in January as a simple transposition to a rigid board, September brought Belterrino Nano as a short-BOM2 version, and last week saw the release of Belterrino V3, made to control Ronilson's robots, but now also a full home made development board for teaching and learning MCU programming.
Belterrino V3 also uses Atmel's ATmega328 to ease Arduino compatibility, and still has an H Bridge able to control robots' (or other) motors, but includes some new features: a pair of user-controlled buttons and a pair of user-controlled leds, and a connector ready to plug a Bluetooth module.
Think of the children!
These new features are directly tied to Ronilson's robot hobby, but are also great for classroom use, when the focus is the software side of microcontrollers, and not the electronics connections: the low-cost and easy to mount board, with 2 user buttons and 2 leds, an H Bridge and a BT module, has all I/O and user interface needed to test simple applications, minimizing the number of external connections: plug a battery, some motor, and start learning the software side of prototyping.
Just like paper based Belterrino V1, Belterrino V3 is still extra inspiring for the DIY people: Ronilson could have used many kinds of ready made green paint for his board, but he preferred to mix his own tar pit (plus ethanol) based paint. It was cheaper this way in Belterra, he says.
Great work, and nice example of maker attitude. Read all about it (including links to previous posts with videos and schematics) on Ronilson's post (in portuguese).