SYSTEM AND RELATED METHODS FOR SENSING FORCES ON A MOVABLE BARRIER

摘要

An operator system and related methods (10) for sensing forces on a movable barrier (12) includes a motor (52), a trolley (30), and a trolley arm (34) having a first end slidably supported by the trolley (38) and a second end coupled to the movable barrier. The motor moves the trolley arm which in tur n moves the movable barrier. A force detection mechanism (68) is coupled to th e motor to determine a first component force value applied by the motor. A controller (54) receives the first component force value and determines a detected force value by scaling the first component force value with a secon d component force value derived from an angular position of the trolley arm's first end with respect to the trolley. The angular position of the trolley a rm may be fixed or variable. An angle potentiometer (72) is coupled to the trolley arm to generate an angle signal for use as the second component forc e value when the trolley arm's angular position is allowed to vary.