Arduino Yún Interfacing

The Pololu Zumo for Arduino (click to view)

I've been investigating how to connect the Arduino Yún to a motor shield or a Zumo robot. Pololu make a number of Zumo models, some made to work with a small integrated controller, others with an Arduino.

To get some help I contacted Adafruit, Arduino.cc and Pololu, the latter makes the Zumo. Here's a summary of what I learned.

This page will be updated periodically as I learn more.

On connecting a Yún to a Zumo robot#

I contacted Pololu about connecting a Yún to their mini Zumo robot. The Zumo acts as an Arduino Shield, plugging right on top of the Zumo (upside down).

It's designed for an Arduino Uno or Leonardo and the issue is that the Yún gets its power via the Vin pin and that power must be a 5 volt regulated supply — much higher and you'll burn out the Yún. This is described, along with a solution, below. [This is included here with permission.]

Hello, Murray.
Zumo Modifications (click to enlarge)

Thank you for your interest in our Zumo robot.  The Zumo shield supplies 7.45V to VIN, so you cannot use the shield in its default configuration to power a Arduino Yún Rev 2.  One way you could work around this is by cutting a trace on the bottom side of the board (the side with no components).  I attached a picture showing where to cut if you go that route (red line).  Then you would need to connect a regulated 5V source to one of the pins in I put a green box around or to the 5V bus.

If you want to avoid cutting traces, another option would be to keep the VIN header disconnected.  If you get the unassembled kit version of our Zumo for Arduino, you could just not solder a header pin to VIN.  If you get the assembled kit, you could just cut that header so that it does not make a connection when you attach your Arduino.  In either of those cases you would need to connect a regulated 5V source to the 5V bus.  In this case, make sure you do not connect your 5V source to any of the pins on the VIN bus! For a 5V source, you might consider one of our 5V step-up/step-down regulators, such as our S7V7F5:

https://www.pololu.com/product/2119

I recommend powering your regulator from VBAT; there is an exposed VBAT and GND pin you might use next to the Pololu logo.

Please let me know if you have any further questions or concerns.

Sincerely,
Patrick Messimer
www.pololu.com
..............................
Pololu Corporation
920 Pilot Rd.
Las Vegas, NV  89119
USA

Arduino Motor Shield V2 Compatibility #

The Adafruit Motor Shield V2 (click to view)

I contacted Adafruit via their forum and asked if their Adafruit Motor/Stepper/Servo Shield for Arduino v2 Kit - v2.3 is compatible with the Arduino Yún.

The full thread can be read here.

In a nutshell, while they don't have any hands-on experience with the Yún, but the Adafruit Motor Shield looks to be compatible and the board power doesn't seem to be an issue, i.e., the Yún powers the Motor Shield, not the other way around. To quote: "Motor power is a separate circuit. If you remove the VIN jumper, you can provide motor power via the motor power terminals on the shield."

Summary#

So it looks like it'd be possible to either build a Zumo-based robot with the Yún, or one using the Adafruit Motor Shield V2 as the motor controller.