Pickle error when training SSD MobileNet

Yes, other people on the forums have re-built PyTorch for Python 3.7 with CUDA enabled (although doing so for Python 3.8 seems more common). There are general compiling instructions for PyTorch under the Build from Source section of this post:

You will probably want to explicitly call python3.7 and pip3.7 instead of python3 and pip3 in those commands, though. Also, soon after the build begins, PyTorch will print out it’s build configuration, will let you know if it detected/enabled CUDA in the build or not.

Presumably your servo motor controller is used during runtime - during training, perhaps you could still just use Python 3.6. You could use the jetson-inference docker container for training, it already has PyTorch/ect installed in it.