Sounds like a fun project!
Have you looked here...
https://www.raspberrypi.com/products/build-hat/
and here
https://www.raspberrypi.com/documentati ... ml#content
I notice that it says....
"Connect an external power supply — the official Raspberry Pi Build HAT power supply is recommended — however any reliable +8V±10% power supply capable of supplying 48W via a DC 5521 centre positive barrel connector (5.5mm × 2.1mm × 11mm) will power the Build HAT. "
I would be suspicious as to whether 5 AA batteries would provide enough power. Their voltage tends to drop quite quickly with load too. The fact that it did work but after a few goes it doesn't, supports that hypothesis.
I would suggest that you try it with an official power supply to see if that works...If it does; then you know that the problem is the power source and you can look at alternatives. I've not use the build hat specifically; but when I've done stuff with motors on Arduinos and Picos; I've tended to go with 18650 batteries...They seem to work quite well. They are often used in things like power tools and electric cars/bikes....
https://en.wikipedia.org/wiki/18650_battery
Have you looked here...
https://www.raspberrypi.com/products/build-hat/
and here
https://www.raspberrypi.com/documentati ... ml#content
I notice that it says....
"Connect an external power supply — the official Raspberry Pi Build HAT power supply is recommended — however any reliable +8V±10% power supply capable of supplying 48W via a DC 5521 centre positive barrel connector (5.5mm × 2.1mm × 11mm) will power the Build HAT. "
I would be suspicious as to whether 5 AA batteries would provide enough power. Their voltage tends to drop quite quickly with load too. The fact that it did work but after a few goes it doesn't, supports that hypothesis.
I would suggest that you try it with an official power supply to see if that works...If it does; then you know that the problem is the power source and you can look at alternatives. I've not use the build hat specifically; but when I've done stuff with motors on Arduinos and Picos; I've tended to go with 18650 batteries...They seem to work quite well. They are often used in things like power tools and electric cars/bikes....
https://en.wikipedia.org/wiki/18650_battery
Statistics: Posted by kip_the_elder — Fri Jul 18, 2025 11:13 am