A passive self-adjusting seat assembly for a lawn maintenance vehicle having a frame. The passive self-adjusting seat assembly includes a base, a guide assembly attached to the base, and a platform assembly that is selectively movable or slidable relative to the guide assembly in order to maintain an operator in an upright or substantially vertical orientation as the lawn maintenance vehicle traverses uneven or sloped ground. The seat assembly further including a locking assembly for selectively locking the sliding or movement of the platform assembly relative to the guide assembly.

A grass trimmer includes an operating device configured for a user to operate and a grass trimmer device including a grass trimmer head and a motor. The grass trimmer head includes a spool configured for a grass trimmer line to wind around and a housing formed with an accommodating cavity. When the grass trimmer is mounted with the grass trimmer line, a part of the grass trimmer line protruding outside the housing is defined as an effective part of the grass trimmer line. The grass trimmer further includes a controller configured to control the grass trimmer head to release a grass trimmer line when the grass trimmer head is mounted with the grass trimmer line and a length of the effective part is detected to be less than or equal to a preset value.

A method of controlling an angular orientation of an agricultural combine having a chassis includes: determining a slope angle of the ground over which the combine is traveling; determining a tilt angle of the chassis; receiving an angle signal from an operator input device; combining the slope angle of the ground and the angle signal from the operator input device to calculate a desired angle of the chassis that is greater than horizontal (0) and less than the slope angle of the ground.

A method of controlling an angular orientation of an agricultural combine having a chassis includes: determining a slope angle of the ground over which the combine is traveling; determining a tilt angle of the chassis; receiving an angle signal from an operator input device; combining the slope angle of the ground and the angle signal from the operator input device to calculate a desired angle of the chassis that is greater than horizontal (0) and less than the slope angle of the ground.

A lateral tilt control system for an agriculture harvester may include first and second tilt cylinders coupled between a support structure and an implement of the harvester. The first tilt cylinder may include a first cap-side chamber and a first rod-side chamber and the second tilt cylinder may include a second cap-side chamber and a second rod-side chamber. The system may also include a first fluid line providing a flow path between the first cap-side chamber and the second cap-side chamber and a second fluid line providing a flow path between the first rod-side chamber and the second cap-side chamber. Additionally, the system may include a pressure relief valve coupled between the first and second fluid lines to allow fluid to be transferred between the first and second fluid lines when a fluid pressure within either fluid line exceed a relief pressure setting.

A lateral tilt control system for an agricultural harvester may include first and second tilt cylinders coupled between a support structure and an implement of the harvester. The first tilt cylinder may include a first cap-side chamber and a first rod-side chamber and the second tilt cylinder may include a second cap-side chamber and a second rod-side chamber. The system may also include a first fluid line providing a flow path between the first cap-side chamber and the second rod-side chamber and a second fluid line providing a flow path between the first rod-side chamber and the second cap-side chamber. Additionally, the system may include a pressure relief valve coupled between the first and second fluid lines to allow fluid to be transferred between the first and second fluid lines when a fluid pressure within either fluid line exceeds a relief pressure setting.

There are provided an engine controlling section for controlling a rotational speed of an engine, a horizontal posture controlling section for rendering a vehicle body frame to a horizontal posture by controlling a posture changing mechanism configured to change a posture of the vehicle body frame by an operation of an actuator utilizing power from the engine, a yield measuring section for measuring a yield of grains stored in a grain tank based on measurement result of a load cell configured to measure a weight of the grain tank, an activation operational tool for outputting an activation signal for activating yield measurement by the yield measuring section, and a yield controlling section configured to provide the engine controlling section with a high speed rotation instruction for driving the engine at a rated rotational speed in response to the activation signal and also to provide the horizontal posture controlling section with a horizontal posture instruction for rendering the vehicle body frame to the horizontal posture.

A lateral tilt control system for an agricultural harvester may include first and second tilt cylinders coupled between a support structure and an implement of the harvester. The first tilt cylinder may include a first cap-side chamber and a first rod-side chamber and the second tilt cylinder may include a second cap-side chamber and a second rod-side chamber. The system may also include a first fluid line providing a flow path between the first cap-side chamber and the second rod-side chamber and a second fluid line providing a flow path between the first rod-side chamber and the second cap-side chamber. Additionally, the system may include a pressure relief valve coupled between the first and second fluid lines to allow fluid to be transferred between the first and second fluid lines when a fluid pressure within either fluid line exceeds a relief pressure setting.

A mower includes: driving devices respectively provided on a right side and a left side of the mower and configured to be driven independently; and one or more processors configured to: estimate a gradient of a slope on a travel path; and drive the driving devices with different driving forces on the right side and the left side based on the estimated gradient such that the mower does not slip down the slope when the mower travels in a direction crossing the slope.