If you just want your node to make progress synchronizing toward the chaintip, it is unnecessary to run the binary with the graphical user interface (bitcoin-qt). You could just run the headless program (bitcoind) instead.
Bitcoin Core will only permit a single instance to use a data directory at the same time, so calling bitcoind again will not start another instance if one is already running. You could therefore have a cronjob that just tries to start bitcoind every five minutes, e.g., you could put into your crontab:
*/5 * * * * bitcoind -daemon
That said, it is entirely unexpected that your Bitcoin Core is crashing every hour. As mentioned in the comments on your other question, you might want to run some system checks to test for hardware failures. As you mentioned there that your node has 8 GB of RAM, you may want to consider increasing your DBCache from the default value to synchronize more quickly after you figure out the underlying issue for the crashes.
