Door assembly having a soft bottomed door panel and system and method of driving the same

A door assembly comprising:

• a door panel having a top edge, a bottom edge, a first vertical edge and a second vertical edge,
• the door panel being fixed proximate the top edge to a drum, the drum being rotatable in a first direction and a second direction, wherein rotation in the first direction causes the door panel to wind onto the drum, and rotation in the second direction causes the door panel to unwind from the drum;
• a first side column and a second side column, wherein the first side column is positioned proximate a first side of a doorway and the second side column is positioned proximate a second side of the doorway, the first side column and the second side column each comprising a guide track, each guide track being positioned to guide one of the first vertical edge or the second vertical edge of the door panel as it blocks and unblocks the doorway;
• a first column of drive teeth positioned along the first vertical edge and a second column of drive teeth positioned along the second vertical edge, wherein each of the first column of drive teeth and the second column of drive teeth are formed by a plurality of adjacent drive teeth, each drive tooth in each plurality of adjacent drive teeth having a cylindrically shaped exterior and arranged in the first column of drive teeth or the second column of drive teeth so that a height of each cylindrically shaped exterior extends vertically along the first vertical edge or the second vertical edge of the door panel so at least a portion of a top of each cylindrically shaped exterior of each drive tooth abuts at least a portion of a bottom of any cylindrically shaped exterior of an immediately adjacent drive tooth as the door panel is wound and unwound from the drum;
• wherein a portion of each cylindrically shaped exterior is removed to form an engagement tooth along the height of each drive tooth, the engagement tooth extending transverse to the height of the drive tooth.