A system for grading filling of a suspension system includes: a pump control module configured to, during first and second periods, operate an electric pump of the suspension system in first and second directions and decreasing and increasing hydraulic fluid pressure within the suspension system, respectively; a monitoring module configured to: store a first pressure of hydraulic fluid within the suspension system measured using a pressure sensor when the first pressure is less than or equal a first predetermined pressure while the pump is operated in the first direction; and store a second pressure measured using the pressure sensor when the second pressure is greater than or equal a second predetermined pressure while the pump is operated in the second direction; and a grade module configured to determine a grade value for the filling of the suspension system based on the first and second pressures.

An air management system for a vehicle having a first pneumatic circuit and a second pneumatic circuit, in which the first and second pneumatic circuits are pneumatically connected in a neutral position via a cross-flow mechanism. The first pneumatic circuit is configured to independently adjust air pressure of a first side of the vehicle. The second pneumatic circuit is configured to independently adjust air pressure of a second side of the vehicle. The system is configured to establish pneumatic communication between the first and second pneumatic circuits when the air management system is not independently adjusting the adjust air pressure of the first side of the vehicle and the air pressure of the second side of the vehicle in the cross-flow mode.

An air management system for a vehicle having a first pneumatic circuit and a second pneumatic circuit, in which the first and second pneumatic circuits are pneumatically connected in a neutral position via a cross-flow mechanism. The first pneumatic circuit is configured to independently adjust air pressure of a first side of the vehicle. The second pneumatic circuit is configured to independently adjust air pressure of a second side of the vehicle. The system is configured to establish pneumatic communication between the first and second pneumatic circuits when the air management system is not independently adjusting the adjust air pressure of the first side of the vehicle and the air pressure of the second side of the vehicle in the cross-flow mode.

A system includes: a state module configured to selectively set a present state to a first state; a valve control module configured to determine first target open and closed states for valves of a suspension system based on the present state and to open and close the valves according to the first target open and closed states, respectively; a pump control module configured to, when the valves are in the first target open and closed states, respectively, selectively operate an electric pump in a first direction to increase hydraulic fluid pressure in a first portion of the suspension system; and a leak module configured to selectively diagnose a leak in a first one of the valves associated with the first state based on a first pressure in the first portion of the suspension system while the valves are open and closed according to the first target open and closed states.

A suspension system and associated control methods for improving the effectiveness of driver assistance systems is disclosed where the driver assistance systems can generate and send requests to a suspension control unit (SCU) of the suspension system to actuate (e.g., close) one or more comfort valves in the suspension system to increase the roll stiffness and/or pitch stiffness of the suspension system when the driver assistance systems are taking corrective action. As part of a two-way communication between the suspension control unit (SCU) and the driver assistance systems, the suspension control unit (SCU) communicates target stiffnesses and/or calculated effective stiffnesses to the driver assistance systems, which is used to update the vehicle stability models used by the driver assistance systems.

The invention relates to a tracked vehicle (10; 11) comprising a vehicle body (30, 32; 30), at least one track assembly (21) and a suspension device (S) for suspension of said track assembly (21) to said vehicle body (30) of said tracked vehicle (10; 11). Said track assembly (21) comprises a track support beam (22), a plurality of road wheels (23, 23a), at least one drive wheel (24), and an endless track (25). Said track support beam (22) is arranged to support said at least one drive wheel (24) and a plurality of road wheels (23, 23a). Said endless track is disposed around said at least one drive wheel (24) and plurality of road wheels (23, 23a). Said suspension device (S) comprises two pendulum arms (52, 54) which in one end are rotatably attached to a respective fastening point (P1b, P2b) in said vehicle body (30; 32, 30) and in the other end are rotatably attached to a respective fastening point (P1a, P2a) in the track support beam (22) of said track assembly (21). Said suspension device (S) comprises distance adjustment means (58) which is arranged to allow one or more of: a distance change between said two fastening points (P1a, P2a) in the track assembly (21); a distance change between the two fastening points (P1b, P2b) in the vehicle body (30); and a distance change between the fastening point (P1b, P2b) in the vehicle body (30; 32, 30) and the fastening point (P1a, P2a) in the track support beam (22) of said track assembly (21) of at least one of the pendulum arms (52, 54), so as to allow a tilting movement of the track assembly (21), including said at least one drive wheel (24) and plurality of road wheels (23, 23a), relative to the vehicle body in a plane extending in the longitudinal direction of said track assembly (21) essentially orthogonal to the transversal extension of said track assembly (21).

The invention relates to a tracked vehicle (11) comprising a vehicle body (30), at least one track assembly (21) and a suspension device (S). Said track assembly (21) is arranged to be supported by said vehicle body (30) by means of said suspension device (S), said track assembly comprising a track support beam (22) for supporting a plurality of road wheels (23, 23a), an endless track (25) being disposed around said road wheels. Said suspension device (S) comprises a bogie arrangement (50) rotatably attached to a fastening point (P0) of said vehicle body (30) about an axis of rotation (Z0) transversal to the longitudinal extension of said track assembly (21) and attached to said track support beam (22) in connection to at least two fastening points (P1, P2) so that the track support beam (22) is allowed to rotate in a rotational plane extending along the longitudinal extension of said track support beam (22) about said axis of rotation.

Disclosed herein are hydraulic actuators and methods for the operation of actuators having variable relative pressure ratios. Further disclosed are methods for designing and/or operating a hydraulic actuator such that the actuator exhibits a variable relative pressure ratio. In certain embodiments, the relative pressure ratio of the hydraulic actuator may be dependent on one or more characteristics (such as, for example, frequency or rate of change) of an oscillating input to the hydraulic actuator.

A damper assembly includes an outer cylinder, an inner cylinder, a plunger, a passage, and a piston. The inner cylinder is positioned at least partially within the outer cylinder and has a cap attached to one end thereof. The plunger is positioned radially inward from the inner cylinder and coupled to a rod. The plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber. The passage extends through the rod and is fluidly coupled with the first chamber. The piston is coupled to the inner cylinder and extends radially outward toward the outer cylinder. The piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber. The plunger is configured to move relative to the inner cylinder, and the piston is configured to move relative to the outer cylinder.

A damper assembly includes an outer cylinder, an inner cylinder, a plunger, a passage, and a piston. The inner cylinder is positioned at least partially within the outer cylinder and has a cap attached to one end thereof. The plunger is positioned radially inward from the inner cylinder and coupled to a rod. The plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber. The passage extends through the rod and is fluidly coupled with the first chamber. The piston is coupled to the inner cylinder and extends radially outward toward the outer cylinder. The piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber. The plunger is configured to move relative to the inner cylinder, and the piston is configured to move relative to the outer cylinder.