is it normal to work as an university professor in engineering but have no real professional experience (in the industry)?
What are my best options to get some professional experience in the field?

You could get a secondment to a company to do specific (applied) research for example.
When I was a student, some of the best professors had spent time in both industry and academia. One I remember had used temperature sensors to record brake disk temperatures on a testing rig - they were glowing... So he was slightly amused at how we were finding it difficult to calibrate a temperature sensor for use between ambient and 100 deg C... He got us sorted though.