If you are running aircrack, then you may need another daemon to monitor the router status.
But if the router dies, then the script may not work as well.
I am not sure how aricrack makes the router die. You may need to debug this problem if you want. It is a driver or software problem, not the router itself.
A hardware watchdog has to be added if you do want to reset the router if it dies. But this is not possible in the current hardware.