Sawppy was a great ice breaker as I roamed through the expo hall of SCaLE 17x. It was certainly the right audience to appreciate such a project, even though there were few companies with products directly relevant to a hobbyist Mars rover. One notable exception, however is the BeagleBoard Foundation booth. As Sawppy drove by, the reception was: “Is that a Raspberry Pi? Yes it is. That should be a BeagleBone Blue!”
With this prompt, I looked into BBBlue in more detail. At $80 it is significantly more expensive than a bare Raspberry Pi, but it incorporates a lot of robotics-related features that a Pi would require several HATs to reach parity.
All BeagleBoards offer a few advantages over a Raspberry Pi, which the BBBlue inherits:
- Integrated flash storage, Pi requires a separate microSD card.
- Onboard LEDs for diagnosis information.
- Onboard buttons for user interaction – including a power button! It’s always personally grated me a Raspberry Pi has no graceful shutdown button.
Above and beyond standard BeagleBoards, the Blue adds:
- A voltage regulator, which I know well is an extra component on a Pi.
- On top of that, BBBlue can also handle charging a 2S LiPo battery! Being able to leave the battery inside a robot would be a huge convenience. And people who don’t own smart battery chargers wouldn’t need to buy one if all they do is use their battery with a BBBlue.
- 8 PWM headers for RC-style servo motors.
- 4 H-bridge to control 4 DC motors.
- 4 Quadrature encoder inputs to know what those motors are up to.
- 9-axis IMU (XYZ accelaration + XYZ rotation)
Sadly, a BBBlue is not a great fit for Sawppy because it uses serial bus servos making all the hardware control features (8 PWM header, 4 motor control, 4 quadrature input) redundant. But I can definitely think of a few projects that would make good use of a BeagleBone Blue. It is promising enough for me to order one to play with.