Patent ID: 8620610

Claim:
A method of determining the attitude and heading angle of a crane jib, comprising the steps of: sensing crane jib angular velocity; sensing crane jib roll angle; sensing crane jib pitch angle; sensing specific force acting on a portion of the crane jib; sensing local magnetic field at least proximate the crane jib; supplying the sensed crane jib angular velocity, the sensed crane jib roll angle, the sensed crane jib pitch angle, the sensed specific force, and the sensed local magnetic field to a processor; and in the processor: computing crane jib translational velocity from the sensed crane jib angular velocity and the sensed specific force; computing crane jib acceleration using the computed crane jib translational velocity and the sensed crane jib angular velocity; using the computed crane jib acceleration to remove crane jib acceleration components from the sensed crane jib roll angle and the sensed crane jib pitch angle, and to thereby supply corrected crane jib roll angle measurements and corrected crane jib pitch angle measurements; applying calibration parameters to the sensed local magnetic field, to thereby supply calibrated magnetic field measurements; computing crane jib heading angle from the calibrated magnetic field measurements; and using the corrected crane jib roll angle measurements, the corrected crane jib pitch angle measurements, and the computed crane jib heading angle, to estimate the attitude and heading angle of the crane jib.