A milling machine has a frame, ground engaging tracks that support the frame, a first actuator connecting the frame to a first track of the ground engaging tracks and a second actuator connecting the frame to a second track from the ground engaging tracks. The milling machine has an orientation sensor that determines an orientation of the frame. The milling machine has a controller that operates the first and second actuators to raise or lower the frame. The controller determines the frame orientation using the orientation sensor. The controller also determines a velocity error between actuator velocities of the first and second actuators based on the frame orientation and a target orientation of the frame. The controller determines a control parameter for the second actuator based on the velocity error and operates the second actuator using the determined control parameter.

Systems to control movement of a motor grader include a sensor for providing a bounce signal indicative of a bouncing movement of the motor grader, and a controller programmed with instructions that, when executed: receive the bounce signal from the sensor; analyze the bounce signal from the sensor; determine whether the maximum amplitude of the bouncing movement exceeds a threshold; in response to determining whether the maximum amplitude exceeds the threshold, generate an articulation angle command signal to change an articulation angle of the motor grader; and transmit the articulation angle command signal to change the articulation angle.

A work vehicle including: a first link having one end portion supported by a vehicle body so as to be pivotable; a second link having one end portion pivotally coupled to the other end portion of the first link so as to be pivotable, and another end portion that supports a travel wheel; a first hydraulic cylinder capable of changing a swing posture of the first link; and a second hydraulic cylinder capable of changing a swing posture of the second link relative to the first link. The action of the first hydraulic cylinder is controlled such that a swing position of the first link is located at a target position, based on the result of detection performed by a position detection sensor, and the action of the second hydraulic cylinder is controlled such that thrust has a target value, based on the results of detection performed by pressure sensors.

A motor grader having ride control for dampening machine bounce using a DCM assembly rotatably coupled to and suspended from a frame of the motor grader is disclosed. Each lift cylinder for the DCM may have an associated ride control circuit with an accumulator, a ride control conduit fluidly connected to a carry end of the lift cylinder and having a flow restriction element, and a ride control accumulator valve fluidly connected to the accumulator and the ride control conduit and operable to either block or allow fluid communication between the carry end and the accumulator through the flow restriction element. Each rid control circuit may also include a head end valve fluidly connected to between the head end of the lift cylinder and a low pressure fluid reservoir and operable to block or allow fluid communication between the head end and the low pressure fluid reservoir.

A calibration system is disclosed. The calibration system may include a sensor configured to measure a fluid level in a fluid tank of a machine, an actuator that, when actuated, affects a level of the machine, and a controller. The controller may be configured to: command actuation of the actuator at a current; receive, from the sensor and after commanding actuation of the actuator, information identifying the fluid level in the fluid tank; determine, based on the information identifying the fluid level in the fluid tank, whether there is a change to the fluid level in the fluid tank; and set an initiation current for the actuator at the current based on determining whether there is the change to the fluid level in the fluid tank.

Systems and methods for determining a pre-charge gas pressure in a gas-charged hydraulic accumulator are disclosed. For example, systems and methods for determining pre-charged gas pressure of a gas-charged hydraulic accumulator included as part of a vehicle are disclosed. Further, the present disclosure provides for determining a pre-charge gas pressure of a gas-charged hydraulic accumulator using a position sensor. The accumulator may form part of a hydraulic system used to move one part of the vehicle relative to another.

A machine comprises a first ground engaging unit connected to a first leg, a second ground engaging unit connected to a second leg, and a hydraulic system to control heights of the legs, the hydraulic system comprises a fluid circuit to control fluid between the first and second legs, a load holding valve to allow fluid into the fluid circuit, a control valve system to let fluid into the load holding valve, the control valve connected to a hydraulic fluid source and a reservoir, a first lock valve to control flow of fluid between the first and second legs in a first direction, a second lock valve to control flow of fluid between the second and first legs in a second direction, and first and float valves configured to connect the first and second legs to the control valve system, respectively.

A machine comprises a first ground engaging unit connected to a first leg, a second ground engaging unit connected to a second leg, and a hydraulic system to control heights of the legs, the hydraulic system comprises a fluid circuit to control fluid between the first and second legs, a load holding valve to allow fluid into the fluid circuit, a control valve system to let fluid into the load holding valve, the control valve connected to a hydraulic fluid source and a reservoir, a first lock valve to control flow of fluid between the first and second legs in a first direction, a second lock valve to control flow of fluid between the second and first legs in a second direction, and first and float valves configured to connect the first and second legs to the control valve system, respectively.

Systems and methods for determining a pre-charge gas pressure in a gas-charged hydraulic accumulator are disclosed. For example, systems and methods for determining pre-charged gas pressure of a gas-charged hydraulic accumulator included as part of a vehicle are disclosed. Further, the present disclosure provides for determining a pre-charge gas pressure of a gas-charged hydraulic accumulator using a position sensor. The accumulator may form part of a hydraulic system used to move one part of the vehicle relative to another.

A milling machine has a frame, ground engaging tracks that support the frame, a first actuator connecting the frame to a first track of the ground engaging tracks and a second actuator connecting the frame to a second track from the ground engaging tracks. The milling machine has an orientation sensor that determines an orientation of the frame. The milling machine has a controller that operates the first and second actuators to raise or lower the frame. The controller determines the frame orientation using the orientation sensor. The controller also determines a velocity error between actuator velocities of the first and second actuators based on the frame orientation and a target orientation of the frame. The controller determines a control parameter for the second actuator based on the velocity error and operates the second actuator using the determined control parameter.