We are planning to purchase several Zumo robots for our students. The main objective is for the Zumo robot to carry a set of sensors, ideally temperature and humidity sensors, and possibly a GPS and/or LiDAR. I thought about mounting a Raspberry Pi to manage the sensor data and send them via Wifi.
I have the following questions:
1. Is it possible to communicate the Raspberry Pi with the Zumo 2040 robot board easily via USB in order to send certain commands? I know this would not be strictly necessary, but I would like to know whether it is possible. I would also be interested in knowing about any reference projects in this regard.
2. I am considering using a Raspberry Pi Zero 2 W. Could it be powered directly from the battery? What option would you recommend, or would a Raspberry Pi 4 be better?
3. In principle, as I understand it, the Zumo 2040 is a better option than the 32U4, correct?
I know these are basic questions but I appreciate any suggestions since we are going to buy several robots.
You could send serial data from a Raspberry Pi to the Zumo through the USB port. Alternatively, you could use I2C or TTL serial.
The scope of what you want the Raspberry Pi board to do is not entirely clear to me, but if the Raspberry Pi Zero 2W has enough power to do what you want, that might be a better option since it uses less power than the Raspberry Pi 4.
Raspberry Pi boards typically need a stable 5V power source, so powering one directly form the Zumo’s battery is probably not a good idea. You might need a separate 5V regulator like the S13V30F5. You might be able to get by with something smaller like the S13V20F5, but note that Raspberry Pi recommends something that can handle upwards of 2.5A.
You could probably use either Zumo you mentioned, but the Zumo 2040 runs at a higher clock speed and operates at 3.3V (which means you can more easily interface with other 3.3V devices like the Raspberry Pi boards). However, in either case, the Zumo robots only have a couple free I/O pins available for adding extra sensors, so depending on your application, you might need to disable some onboard features to free-up some additional pins. You can refer to the “Adding electronics” section of the respective user’s guides for more details:
Alternatively, you could consider our Romi Robot platform. The Romi 32U4 Control Board has many more free I/O pins and built-in support for adding a Raspberry Pi computer (including a built-in regulator powering it and the required level shifters on the I2C line to communicate with it safely). You can find more details in the “Raspberry Pi interface and level shifters” section of the Romi 32U4 Control Board user’s guide. Additionally, the Romi Robot offers more mounting options for additional devices compared to the Zumo.
Thank you very much for your detailed answer. Just to clarify my second question: I would like the Raspberry Pi board (or another board, such as an ESP32) to manage and connect the additional sensors I add, as well as any potential communication with the Zumo robot controller. The RP2040 controller would therefore be dedicated solely to robot movement.
After reading your post, I think I will choose the Zumo 2040.
