Auto lock after driving relay

Hello again, Many modern cars lock the doors after 30 seconds of the moving. My G/F's 2015 car has software configuration options for this such as lock only drive door, or all doors after driving for 30 seconds (and can be disabled completely). How can this be achieved on a 1997 Lexus SC manual transmission car? How to you tell a relay to turn on after 30 seconds only after it's driving? You can't have the relay activate every time the go goes into first gear, because if you were in traffic you'd be locking your doors every 30 seconds hah! How do you make it do this based on the forward speed sensor?

A Clifford G5 or Compustar alarm or alarm + R/S gives you RPM control, as soon as you accelerate past about 10mph. You could take a pulse from the starter wire or D light at the gear shift trigger and use a Velleman module, trigger, delay, on/off. You should repost this in the relay section, someone there should be able to help.