Start ps3 controller

Hello Forum,
i followed this tutorial:
I have no gopigo, i use the nxt motors, but all works fine if i start my script with putty. I use the dexter image.
Now i want to start my script automaticly. But when i start the pi without a pc the ps3 controller is not loaded. I want to start my script in the crontab. Should i write the bluetooth controller in crontab, too? How can i did it? tahnks for help.