Setting up an automated job under Linux is a cinch thanks to cron. Doing the same under Windows is a little more tricky, but still eminently doable.
I found this tutorial helpful:
That got me 99% of the way there. I wrote a batch file to trigger the script. The critical element was changing to the correct location before invoking R.
@echo off cd "C:\Users\AndrewCo\Projects\" R CMD BATCH script.R