Passenger boarding bridge

A passenger boarding bridge comprising:

• a rotunda connected to a terminal building and rotatable in regular and reverse directions about a vertical axis;
• a tunnel unit whose proximal end is connected to the rotunda in such a manner that the tunnel unit is liftable and lowerable, the tunnel unit being configured to be extendable and retractable in a longitudinal direction of the tunnel unit;
• a cab rotatably provided at a distal end of the tunnel unit, a distal end part of the cab being to be docked with an entrance of an aircraft;
• a lifting/lowering device mounted to the tunnel unit or the cab and configured to lift and lower the tunnel unit or the cab by extending and retracting in a longitudinal direction of the lifting/lowering device;
• a travel device mounted under the lifting/lowering device, the travel device being configured to travel on a ground and rotate in regular and reverse directions about an axis that passes through a center point of the travel device, such that a travel direction of the travel device is changeable;
• a cab rotator configured to rotate the cab;
• first and second cameras mounted to the cab and each configured to capture an image of the entrance of the aircraft;
• and
• a controller configured to control the travel device, the lifting/lowering device, and the cab rotator, wherein
• the controller is configured to express a position of each part of the aircraft and of the passenger boarding bridge as position coordinates by using a three-dimensional orthogonal coordinate system in which a predetermined position is set as an origin, and
• the controller is configured to perform:
• a first entrance position calculation process of causing the first and second cameras to capture images of the entrance, respectively, when the cab is at a predetermined standby position from which the cab is to start moving, and calculating position coordinates of a reference point on the entrance of the aircraft based on the images of the entrance captured by the first and second cameras, respectively;
• a cab stop position calculation process of, based on the position coordinates of the reference point on the entrance calculated in the first entrance position calculation process, calculating target position coordinates of a reference point on the distal end part of the cab at a temporary stop position of the cab, the temporary stop position being such a position that when the cab is at the temporary stop position, the distal end part of the cab is located forward away from the entrance by a predetermined distance;
• a first inverse kinematics calculation process of, based on the target position coordinates of the reference point of the cab at the temporary stop position, the target position coordinates being calculated in the cab stop position calculation process, and a first desired rotational angle of the cab at the temporary stop position with respect to a particular horizontal direction, performing an inverse kinematics calculation to calculate target position coordinates of the center point of the travel device, a target length of the lifting/lowering device, and a target rotational angle of the cab with respect to the tunnel unit for the cab to be at the temporary stop position;
• and
• a first moving process of moving the cab from the standby position to the temporary stop position by performing:
• a process of causing the travel device to travel such that coordinates of the center point of the travel device are brought into coincidence with the target position coordinates calculated in the first inverse kinematics calculation process;
• a process of causing the lifting/lowering device to extend or retract to adjust a length of the lifting/lowering device to the target length calculated in the first inverse kinematics calculation process;
• and
• a process of driving the cab rotator to adjust a rotational angle of the cab with respect to the tunnel unit to the target rotational angle calculated in the first inverse kinematics calculation process.