I don't have a tutorial, but this is how I would achieve this. I would move the hot point of your pendulum the the top axis that will be your rotation axis. I would move the pendulum to the top right most angle that it would move to, then I would go to my Timeline and move "scrub" time to the left. (at this point is not relevant how much since you can tweak it later), this will enter a new key-frame once you move your object to the new position, then do the next position by following these same steps, and so on. Once you have finished with the hole motion from left to right you can copy the key-frames by holding your option/alt key in your keyboard and moving the coped key-frame to the new position in the time line.