I am excited to announce our new A-Star 32U4 Robot Controller LV with Raspberry Pi Bridge, a general-purpose robot controller based on Atmel’s ATmega32U4 microcontroller.
This new robot controller is the latest model in our A-Star line of Arduino-compatible USB microcontroller boards. We started with the A-Star 32U4 Micro and have been gradually expanding the line, adding peripherals and various form-factor and voltage options, with the goal of eventually replacing our older Orangutan robot controllers. The Zumo 32U4 was a major step in that direction, since its controller board is essentially an A-Star 32U4 plus extra peripherals for motor control and sensing. But while the Zumo 32U4 is a complete robot kit, this board is for people who want to design their own robot.
The A-Star 32U4 Robot Controller LV includes most of the features of the A-Star 32U4 Prime LV, including an Arduino-compatible USB bootloader, an efficient step-up/step-down regulator, and handy peripherals like the buzzer and buttons, and it expands on the A-Star line by adding a pair of Texas Instruments DRV8838 1.8 A motor drivers, the same motor drivers as on the Zumo. All of the AVR’s GPIO lines are broken out, and we have included handy power and ground rails so you can easily connect lots of things like servos and sensors:
This board is well-suited for small robots that would have otherwise used an Orangutan controller like the SV-328 or SVP-1284. While we did not include an LCD like on the Orangutans, you can get far better display, monitoring, or data logging by making use of the Raspberry Pi connection, which I will talk about next.
Using the robot controller with a Raspberry Pi
The Raspberry Pi is a great board for an embedded project that needs serious computational power or connectivity. We have released a couple of Raspberry Pi motor driver boards over the past year, which give you a way to get started exploring robotics with your Raspberry Pi. But robotics projects tend to use a lot of analog sensors, timing-sensitive devices like servos, and other peripherals that are not compatible with the limited I/O capabilities of the Raspberry Pi. These types of things are what microcontrollers are designed for, so you can do a lot more if you pair your Raspberry Pi with a complete microcontroller board.
That’s why instead of using the standard Arduino form factor like the Prime, we built the A-Star 32U4 Robot Controller LV to double as a Raspberry Pi HAT:
|A-Star 32U4 Robot Controller LV with Raspberry Pi Bridge on a Raspberry Pi Model B+.|
The Robot Controller fits on top of a Raspberry Pi A+/B+/2, powers the Pi, and connects to it as an I²C slave device, giving you a bidirectional channel of communication between the two processors. We have broken out all of the GPIO of the Raspberry Pi, and there are a few general-purpose level-shifters included on the board to help you experiment with other communications protocols or interface other hardware to your system. We even include the EEPROM required by the HAT specification, though we have not found it to be particularly useful – we ship it blank and unlocked for you to experiment with.
For more information about the A-Star 32U4 Robot Controller LV, or to order, see the product page. You can also check out our open-source A-Star 32U4 Arduino library, which provides easy access to the main features of the Robot Controller, including its motor drivers; we will be adding examples showing I²C communication with the Raspberry Pi soon.