Hi,
I am a student. I broke one odrive while working on a project. So I have a question, do I need an usb to usb isolator between the computer and the USB hub in this schematic?
Not necessarily required, if your computer is grounded or you’ll get a lot of noise then you might want to
Generally yes it’s required. There are only very limited situation when it’s ok to skip the USB isolator, and it’s very rare to see an acceptable situation in a system with several modules.
For example, how are you sending commands to your stepper driver? You probably have some logic board sending the steps. I drew an Arduino here, but it could be something else, and it could be directly connected to PC instead of USB hub, the principle is the same: you have a logic network sharing ground with a power network. This is bad. You get a ground loop that involves the motor power current, which can cause damage to the logic boards.
I drew a ground loop in purple.