Here is a very straight forward sinusoidal sweep with defined dwell times for a servo motor.
the math gets a little tedious as you have to keep track of "t" within the process, but it is fairly easy to edit and watch the updated graph. If the sequence suddenly changes, it will warn you and show you the results.
This one dwells for 3 seconds at 0 degrees; "-1*" inverses the cosine; "(t-3)" resets t to 0; "/4" account for 4 seconds for a 1/2 cosine sweep making t range 0 to 1; "*180" makes the sweep 1/2 cycle; *30 set amplitude (1/2 of overall since the cosine function returns -1 to 1); the "+30" manages the offset to start at the last known position... in this case, 0. Followed by another 3 seconds of dwell, holding at position at 60 degrees. In angle terms... you could divide the time segment into 360 steps and you time would equal 1 degree per value of "t".
Be sure the domains remain continuous.