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Got all four drivers wired to the perfboard power rails and the motors connected. Immediately blew a fuse. The Nano setup took longer than I expected. The factory image hung on boot, so I flashed JetPack 4.6.6 fresh from a microSD, forgot the password, flashed again.

The Jetson Nano has no software PWM, but it does have two hardware PWM channels on pins 32 and 33, disabled by default. I found this in someone's blog. The fix is running jetson-io.py to enable them. Once that was done, the first motor spun immediately.

Two PWM channels isn't enough for four motors, so I moved to a PCA9685. It talks to the Nano over I2C on pins 3 and 5, and I ran a PWM signal line from each of its 16 channels to the drivers. For the Nano's power I'm building a 5V pack from 18650 cells in parallel through an XL6009 boost converter.

I'm picking up an old project I've restarted a couple of times: my 4-wheel rover. The first build ran two L298N dual drivers on regular wheels and a plastic chassis. That one got stolen. The replacement uses TB9051FTG drivers, mecanum wheels, and a metal chassis.

The motors run off two 3.7V LiPo batteries with a blade fuse soldered onto the positive line and XT30s on the ends. That's as far as I've gotten. I need to keep ordering parts, and it's turning into an expensive robot.