Abstract: A sonar device for controlling movement of an object such as a transport drawer for delivery of material or things under security conditions to a customer. Examples of such transport drawers are bank drive-up window deal drawers or similar deal-type drawers for secure delivery and sale of pharmaceuticals fast foods, library books and packages of valuable things. The sonar device detects when a predetermined fixed distance has been established or occurs between a moving object such as a banking equipment deal drawer, and an object or body such as a vehicle being served by or using the drawer; and signals that the fixed distance exists, which signal may trigger stopping of a motor drive for the drawer to avoid collision of the drawer with the vehicle.