Bus Track Version 1:

In this version, firstly, you can set the minute you want to be reminded by the motor from 3 to 20 minutes (by adjusting the "bustimeleftset"): 

And then this time will be divided into three phases:

In the first 50% time, the motor will perform a slow speed (default :500) (you can adjust)

 In the 50% to 30% time, the motor will perform a medium speed (default :300) (you can adjust, but is limited to be smaller than the first one)

 In the 30% to 10% time, the motor will perform a fast speed (default :100) (you can adjust, but is limited to be smaller than the second one)

In addition, you can adjust the motor frequency in every phase by adjusting the value "motortimes" and how many times 

Tips: The time every phase remain after motor performs will be calculate by the function: minite*timelef*phaseX - motortimes*delayX*2

which can automatically make up the time to every phase should last.