Power

The car carries its own power. Its JGB37-520 DC drive motors (12 V, 550 RPM) are fed from a 3S LiPo through the AT8236 Motor Controller, while the compute boards (Jetson Orin Nano, Raspberry Pi 5, Zero 2 W) run from high-output USB power banks. Separating the noisy motor rail from the clean logic rail is the main goal of the power design.

Parts (Amazon)

Power Domains

  • Motor rail: a 3S LiPo (11.1 V; for example, the OVONIC 3S 5,200 mAh) feeds the AT8236 Motor Controller and JGB37-520 DC drive motors. A DROK DC buck converter steps voltage down where a rail needs it, and ATC/ATO fuses protect against shorts.
  • Logic rail: the compute boards run from USB power banks (a 27,000 mAh, 140 W bank and a 10,000 mAh, 45 W bank), keeping the Jetson Orin Nano, Raspberry Pi 5, and Zero 2 W off the noisy motor supply.
  • Display rail: a 2S LiPo supplies the HUB75 display through its fused buck converter. A dual LiPo charger/discharger supports the battery set.

How It Works

  • Motors and logic are on separate supplies to reduce how strongly motor start/brake current transients couple into the compute boards. A correctly configured buck converter regulates its downstream rail, and fuses limit fault current. None of those choices makes a brownout impossible.
  • The Zero 2 W needs a stable supply, but a USB enumeration failure does not identify one cause. Power, cable integrity, the host port, and gadget state must be checked separately.

Why This Choice

  • A 3S LiPo delivers the high current the drive motors need at a usable voltage, while USB power banks give the regulated, steady 5 V that the single-board computers expect.
  • Splitting the domains and adding fusing is intended to reduce resets and contain electrical faults. A measured rail-voltage trace would be needed to attribute a particular reset or USB failure to power.