A work machine includes a main body, a boom to drive with respect to the main body, a work tool connecting to the boom, the work tool to drive with respect to the boom, an actuator connecting to the main body and the work tool, the actuator to drive the work tool, and a sub-link to transmit drive of the actuator to the work tool. A method for calibrating the work machine includes outputting a detection value to detect an angle of the sub-link with respect to the boom in a predetermined posture of the boom and a work tool posture, converting the detection value as a measurement angle of the sub-link with respect to the boom based on a conversion value, and calibrating the conversion value based on a relationship between the measurement angle and an actual angle in the work tool posture which is specified.

An excavator with a boom comprises a main electrical drive system with an electrical power storage unit. The excavator comprises an electrical drive configured to actuate movement of the boom to raise and/or lower part of the boom. The excavator comprises a separate fluid-operated, auxiliary actuation system for storing potential energy of the part of the boom during lowering thereof and for using the stored potential energy to support raising of the part of the boom. The auxiliary actuation system is configured to store the potential energy and to support raising the part of the boom autonomously without interaction with the main electrical drive system.

A multiple mode operational system for a work machine may comprise a frame, a ground-engaging mechanism coupled to the frame, an attachment, an object detector, and a multiple mode control system. The multiple mode control system may include a control device and a controller receiving a signal from the control device. The controller may have a first operational mode and a second operational mode. The first operational mode may enable a first sensitivity response to the control device and the second operational mode may enable a second sensitivity response to the control device. The controller may be configured to receive an object signal from the object detector and modify the operational mode of the controller based on a detected distance of the object from a reference point.

Provided is a wheel loader capable of reducing erroneous determination of rear wheel lifting. The wheel loader 1 includes a controller 5 for determining a rear wheel lifting state where rear wheels 11B are lifted upwardly. The controller 5 is configured to, when a temporal change rate α of a bucket operation angle becomes a temporal change rate of a bucket operation angle necessary for a tilt operation of a bucket 23 during an excavation operation and a temporal change rate β of a vehicle body inclination angle estimated by the controller 5 becomes a temporal change rate of an obliquely upward inclination state of a rear vehicle body with respect to a front vehicle body, turn on a correlation flag indicating a correlation between an operation state of the bucket 23 and an inclination state of a vehicle body to determine a rear wheel lifting.

A system for controlling hydraulic fluid flow within a work vehicle includes a pilot conduit configured to receive a pilot flow of hydraulic fluid from a fluid supply conduit such that the operation of a compensator valve is controlled based on a pressure of the pilot flow within the pilot conduit. Furthermore, a pilot conduit valve is configured to adjust the pressure of the pilot flow within the pilot conduit. In addition, the system includes a load sense conduit configured to receive a bleed flow of the hydraulic from the fluid supply conduit such that the operation of the pump is controlled based on a pressure of the bleed flow within the load sense conduit. Moreover, a load sense valve is configured to adjust the pressure of the bleed flow within the load sense conduit.

Vehicles and methods of operating vehicles are disclosed herein. A vehicle includes a main frame, a work implement, and a control system. The work implement is supported by the main frame and configured to carry a payload in use of the vehicle. The control system is supported by the main frame and configured to control operation of the vehicle. The control system includes a payload measurement system configured to provide payload input indicative of a variable payload carried by the work implement in use of the vehicle and a controller coupled to the payload measurement system.

A method for operating a drive system for a work machine is described. A first electric motor is associated with a travel drive of the drive system and a second electric motor is associated with a work drive of the drive system. An electric energy store for operating the first and the second electric motors is associated with the travel drive and the work drive. The method includes operating the first electric motor in generator mode to produce braking power of the travel drive, electric power being produced in the generator mode. The method further includes supplying, completely or partly to the energy store and/or to the second electric motor depending on a state of the energy store, the electric power.

A work vehicle includes a vehicle body, a work implement including an attachment, an operating device and a controller. The operating device can be operated to a dump side and a tilt side to cause the attachment to dump and tilt. The controller executes an automatic drive control in which the attachment is caused to dump as far as a predetermined dumping position when the operating device is operated by a first dump operation amount or greater to the dump side, or to tilt as far as a predetermined tilt position when the operating device is operated by a first tilt operation amount or greater to the tilt side. The controller disables the automatic drive control when a switching time period required for the operating device to be switched between the tilt and dump sides is at least a predetermined disabling time period.

A method is disclosed. The method may include controlling a leading edge of an implement of a machine using a first control loop to cause the implement to align to a defined design plan; controlling a trailing edge of the implement of the machine using a second control loop to cause the implement to align to the defined design plan; and selectively altering a gain to the second control loop based on a detected deviation of the implement from the defined design plan to increase an angle of approach, using the first control loop, when the implement is positioned above the defined design plan and decrease the angle of approach, using the first control loop, when the implement is aligned to the defined design plan.

Vehicles and methods of operating vehicles are disclosed herein. A vehicle includes a main frame, a work implement, and a control system. The work implement is supported by the main frame and configured to carry a payload in use of the vehicle. The control system is supported by the main frame and configured to control operation of the vehicle. The control system includes a payload measurement system configured to provide payload input indicative of a variable payload carried by the work implement in use of the vehicle and a controller coupled to the payload measurement system.