Backfill scheduling techniques are used to schedule execution of applications, either on a local computing unit or a remote unit. When the movement of the driven shaft is obstructed, the motor driver and the switch are synchronized in a manner to first charge the capacitor and then to reverse the voltage generated by the motor driver to momentarily double the voltage applied to the DC motor so that the increased torque of the DC motor is able to overcome the obstruction. The step of designing the plurality of filters also includes designing a lowest-level filter that can become active only when the highest-level filter has become active and when the parser indicates that an element for which the lowest-level filter is searching has been parsed.