Hitachi Construction Machinery Co., Ltd.

Shinichi Kotake

Shiho Izumi

Shinji Ishihara

Yasuhiko Kanari

Hideto Ishibashi

Hyejeoung Lee

A controller provided to a work machine stores a plurality of mask ranges which are used to select positioning satellites to be used by a receiver to compute a position of an antenna and are set with reference to an antenna on the basis of the postures of a work device and an swing structure. The controller computes each of a plurality of positioning precisions on the basis of satellite related data on the positioning satellites each of which is selected through use of each of the plurality of mask ranges and satellite related data on the positioning satellites which are selected through use of none of the plurality of mask ranges. The receiver computes the position of the antenna on the basis of satellite signals of the positioning satellites selected in a case of having the highest positioning precision out of the plurality of computed positioning precisions.

Work machine

A controller sets, as a satellite mask range, a range for which a work implement can become an obstacle when an antenna receives positioning signals from a plurality of positioning satellites on the basis of a position at which the antenna is installed, a movable range of the work implement, a posture of an upper swing structure, and an azimuth angle of the upper swing structure. The controller cancels the setting of the satellite mask range in a case where it has been determined, on the basis of satellite positioning condition data acquired from a receiver, that the setting of the satellite mask range leads to reduced precision of positioning computation by the receiver. In a case where the setting of the satellite mask range has been canceled, the receiver computes the position of the upper swing structure on the basis of the positioning signals transmitted from the plurality of positioning satellites.

Work machine configured to set a mask range in a field of vision over an antenna for which part of the work machine can become an obstacle when receiving positioning signals from satellites

A position/posture computing section determines that an azimuth of an upper swing structure calculated at a GNSS receiver is of low quality when at least one of a posture angle of the upper swing structure acquired at a machine-body IMU and a posture angle of a front work implement acquired at a boom IMU is equal to or larger than a threshold value, executes a bias removal computation on the basis of the quality of the azimuth and the azimuth of the upper swing structure calculated at the GNSS receiver, calculates a corrected azimuth of the upper swing structure on the basis of the azimuth of the upper swing structure calculated at the GNSS receiver, and an angular velocity of the upper swing structure from which a gyro bias has been removed, and computes a three-dimensional position and posture of the front work implement by using the corrected azimuth.

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Tsuchiura, Japan

Shinichi Kotake