Work machine and control device for work machine
A work machine is provided that includes: an attachment attached on an upper rotating body and including at least a boom, an arm attached on an end of the boom, and an end attachment attached on an end of the arm; and a control device, wherein the control device compensates for a torque, which causes the boom to rotate, based on either or both of a centrifugal force on the arm and an inertial force on the arm, and calculates a weight of a conveyance object conveyed by the attachment based on the torque for which the compensation is performed.
1 . A work machine, comprising:
an attachment attached on an upper rotating body and including at least a boom, an arm attached on an end of the boom, and an end attachment attached on an end of the arm;
a posture sensor configured to detect an attitude of the work machine; and
a hardware processor configured to
calculate either or both of an arm centrifugal force torque and an arm inertial force torque based on an output of the posture sensor, the arm centrifugal force torque being a torque about a foot pin of the boom due to a centrifugal force on the arm when the arm is being opened or closed, the arm inertial force torque being a torque about the foot pin of the boom due to an inertial force on the arm when the arm is being opened or closed,
compensate for a torque, which causes the boom to rotate, based on said calculated either or both of the arm centrifugal force torque and the arm inertial force torque, and
calculate a weight of a conveyance object conveyed by the attachment based on the torque compensated for.
2 . The work machine according to claim 1 ,
wherein the torque, which causes the boom to rotate, is a torque about the foot pin of the boom.
3 . The work machine according to claim 1 ,
wherein the hardware processor is configured to compensate for the calculated weight of the conveyance object based on an attitude of the work machine.
4 . The work machine according to claim 1 ,
wherein the hardware processor is configured to calculate the weight of the conveyance object based on the torque during work in which the boom is raised and the arm is opened or closed.
5 . The work machine according to claim 1 ,
wherein the end attachment is a bucket, a lifting magnet, a grapple, a fork, or a harvester including a chainsaw.
6 . The work machine according to claim 1 , further comprising:
a boom cylinder configured to drive the boom,
wherein the hardware processor is further configured to
calculate a detection-target torque that is a torque about the foot pin of the boom calculated based on a pressure of operating oil in the boom cylinder;
calculate an inertial term torque that is a torque about the foot pin of the boom calculated based on an angular acceleration about the foot pin of the boom and a moment of inertia of the boom;
calculate a centrifugal term torque that is a torque about the foot pin of the boom calculated based on an angular velocity about the foot pin of the boom and a weight of the boom;
calculate a stall torque that is a torque about the foot pin of the boom during a stall period of the attachment by subtracting the calculated inertial term torque, the calculated centrifugal term torque, and said calculated either or both of the arm centrifugal force torque and the arm inertial force torque from the calculated detection-target torque; and
calculate the weight of the conveyance object based on the calculated stall torque.
7 . The work machine according to claim 6 , further comprising:
a boom angle sensor configured to detect a boom angle that is an angle of depression or elevation of the boom with respect to the upper rotating body,
wherein the hardware processor is configured to compensate for the calculated weight of the conveyance object by correcting the detected boom angle based on a pitch angle of the work machine.
8 . The work machine according to claim 6 , wherein the hardware processor is configured to compensate for the calculated weight of the conveyance object by correcting a thrust on the boom cylinder based on a roll angle of the work machine.
9 . A work machine, comprising:
an attachment attached on an upper rotating body and including at least a boom, an arm attached on an end of the boom, and an end attachment attached on an end of the arm;
a posture sensor configured to detect an attitude of the work machine; and
a hardware processor configured to
calculate either or both of an end attachment centrifugal force torque and an end attachment inertial force torque based on an output of the posture sensor, the end attachment centrifugal force torque being a torque about a foot pin of the boom due to a centrifugal force on the end attachment when the end attachment is being opened or closed, or rotated, the end attachment inertial force torque being a torque about the foot pin of the boom due to an inertial force on the end attachment when the end attachment is being opened or closed, or rotated,
compensate for a torque, which causes the boom to rotate, based on said calculated either or both of the end attachment centrifugal force torque and the end attachment inertial force torque, and
calculate a weight of a conveyance object conveyed by the attachment based on the torque compensated for.
10 . The work machine according to claim 9 ,
wherein the end attachment is pivotally attached on the end of the arm to be opened or closed, and
the hardware processor is configured to compensate for the torque, which causes the boom to rotate, based on either or both of the centrifugal force on the end attachment and the inertial force on the end attachment, the centrifugal force and the inertial force being due to opening or closing of the end attachment on the arm.
11 . The work machine according to claim 9 ,
wherein the end attachment includes
a grappling portion that grapples the conveyance object, and
a grappling portion rotating mechanism that rotates the grappling portion, and
the hardware processor is configured to compensate for the torque, which causes the boom to rotate, based on either or both of the centrifugal force on the end attachment and the inertial force on the end attachment, the centrifugal force and the inertial force being due to an operation of rotating the grappling portion.
12 . The work machine according to claim 9 ,
wherein the torque, which causes the boom to rotate, is a torque about the foot pin of the boom.
13 . The work machine according to claim 9 ,
wherein the hardware processor is configured to compensate for the calculated weight of the conveyance object based on an attitude of the work machine.
14 . The work machine according to claim 9 ,
wherein the hardware processor is configured to calculate the weight of the conveyance object based on the torque during work in which the boom is raised and the end attachment is rotated.
15 . The work machine according to claim 9 , further comprising:
a boom cylinder configured to drive the boom,
wherein the hardware processor is further configured to
calculate a detection-target torque that is a torque about the foot pin of the boom calculated based on a pressure of operating oil in the boom cylinder;
calculate an inertial term torque that is a torque about the foot pin of the boom calculated based on an angular acceleration about the foot pin of the boom and a moment of inertia of the boom;
calculate a centrifugal term torque that is a torque about the foot pin of the boom calculated based on an angular velocity about the foot pin of the boom and a weight of the boom;
calculate either or both of an arm centrifugal force torque and an arm inertial force torque, the arm centrifugal force torque being a torque about the foot pin of the boom due to a centrifugal force on the arm when the arm is being opened or closed, the arm inertial force torque being a torque about the foot pin of the boom due to an inertial force on the arm when the arm is being opened or closed;
calculate a stall torque that is a torque about the foot pin of the boom during a stall period of the attachment by subtracting the calculated inertial term torque, the calculated centrifugal term torque, said calculated either or both of the arm centrifugal force torque and the arm inertial force torque, and said calculated either or both of the end attachment centrifugal force torque and the end attachment inertial force torque from the calculated detection-target torque; and
calculate the weight of the conveyance object based on the calculated stall torque.
16 . The work machine according to claim 15 , further comprising:
a boom angle sensor configured to detect a boom angle that is an angle of depression or elevation of the boom with respect to the upper rotating body,
wherein the hardware processor is configured to compensate for the calculated weight of the conveyance object by correcting the detected boom angle based on a pitch angle of the work machine.
17 . The work machine according to claim 15 , wherein the hardware processor is configured to compensate for the calculated weight of the conveyance object by correcting a thrust on the boom cylinder based on a roll angle of the work machine.