Tag Archives: HUB-ee wheels

ATmega32U4 drives open source LEO ‘bot

The Creative Robotics crew has debuted LEO, an open source robotic kit powered by Atmel’s versatile ATMega32U4 microcontroller (MCU).


Additional key specs include an Arduino bootloader, 12 digital I/O pins via an I2C port expander, configurable pull up/down and interrupt capable, 6 digital I/O directly connected to the ATMega32U4 MCU, two PWM capable pins, four external interrupt capable pins, USART and I2C Serial ports, 12 analog inputs, user programmable button, as well as a ‘COMM Hood’ and ‘IO Hood’ comms expansion system.

Leo also features (dual) four wheel and tracked configurations, front and rear tactile bumpers, dual HUB-ee motor plus slave motor connections, dual wheel quadrature encoder reading (128 counts per revolution), dual motor current feedback, automatic motor disable when powered by USB, Arduino robot compatible connector/mounting holes, as well as comprehensive firmware supporting encoders, external IO, PID Speed control and a serial command set.

“LEO is the product of over a decade of design experience in building autonomous robots, experience that also inspired the creation of our HUB-ee wheels,” a Creative Robots rep explained in a recent Kickstarter post.

“Unlike most small robotic platforms on the market LEO can be reconfigured from simple symmetrical two wheel drive to four wheel drive in a matter of minutes – and [is packaged] with a pair of modular tactile bumpers at each end for basic obstacle detection.”

LEO is also quite moddable, as Makers can easily add expansion boards using a dual ‘Hood’ stacking system.

“Hoods are a bit like shields, you can use them to add functionality like extra processors, manual controls, sensors and wireless radios. We call them hoods because LEO is a vehicle (and cars have hoods) and also to differentiate them from the shield system,” said the rep.

“LEO can have two different types of hood at the same time, one for general analog and digital I/O and a second just for serial and I2C communications. This allows you to fit LEO with a Bluetooth, ZigBee or Wifi module without interfering with the general purpose I/O.”

As noted above, Leo is an open source robot project, with all the PCB schematic design files, CAD files for the bumper and caster wheel available for download under the creative commons attribution sharealike license. Software libraries will also be accessible on GitHub.

Interested in learning more? You can check out LEO’s official Kickstarter page here.