A suspension system including four dampers where each damper includes compression and rebound chambers. The suspension system has four hydraulic circuits, each including a cross-over hydraulic line that extends between dampers located at opposite corners of the vehicle (i.e., between the front left and back right dampers or between the front right and back left dampers). The suspension system further includes four electromechanical comfort valves that open and close four bridge hydraulic lines that extend between the cross-over hydraulic lines at each corner of the vehicle. Each cross-over hydraulic line is connected to a manifold assembly by a corresponding manifold hydraulic line. The manifold assembly includes four manifold valves that are connected to a pump assembly and two manifold comfort valves. All six comfort valves are electromechanical valves that can be actuated to control the roll and pitch of the vehicle during cornering, braking, and acceleration.

A control system includes: a target volume module configured to determine a target volume of hydraulic fluid within a suspension system of a vehicle based on a target pressure of the hydraulic fluid within the suspension system; a volume command module configured to generate a volume command based on the target volume and a present volume of the hydraulic fluid within first and second circuits; a command module configured to, based on the volume command, generate: a pump command for an electric hydraulic fluid pump; and first and second valve commands for first and second seat valves that regulate hydraulic fluid flow to and from the first and second circuits, respectively; a valve control module that actuates the first and second seat valves based on the first and second valve commands, respectively; and a pump control module that controls operation of the pump based on the pump command.

A semi-trailer for transporting a load to be moved has a wheeled front module having a right-hand front row and a left-hand front row of front bogies each provided with a respective hydraulic suspension driven by its own hydraulic cylinder; a wheeled rear module comprising a right-hand rear row and a left-hand rear row of rear bogies each provided with a respective hydraulic suspension driven by its own hydraulic cylinder; a coupling unit of the wheeled front module for the coupling to a tractor and comprising a pair of hydraulic jacks for transferring a part of the load to be moved to the tractor; a first hydraulic unit interposed between the hydraulic cylinders of the front and rear rows of bogies and configured in such a way that the sum of the instantaneous load-supporting pressures acting on the hydraulic cylinders of the right front row and of the cylinders of the left-hand rear row is equal to the sum of the instantaneous pressures controlling the cylinders of the left-hand front row and of the cylinders of the right rear row; and a second hydraulic unit configured to control the hydraulic jacks based on the sum of the instantaneous load-supporting pressures acting on the hydraulic cylinders of said right front row and of said left-hand front row.

A method of automatically applying damping force interventions for dynamic weight balancing in a suspension system of a vehicle may include receiving ride height information associated with respective individual wheels of the vehicle and vehicle attitude information from vehicle sensors, determining, based on the ride height information and the vehicle attitude information, whether a trigger event has occurred, and generating a first damping intervention signal to change a damping force applied by a first selected adjustable damper responsive to determining that the trigger event has occurred. The first selected damper may be one of a plurality of adjustable dampers associated with respective ones of the individual wheels of the vehicle. The first selected adjustable damper may be associated with only one of a pair of rear wheels of the vehicle.

Cross-linked vehicle suspension systems. A first wheel is mechanically linked to a second wheel by a cross tie, so that motion from an impact with an obstacle by the first wheel is transmitted to the second wheel. A shock absorber may be coupled to each wheel, the cross tie, or both, to distribute absorption of the impact. In some embodiments, a second pair of wheels may be coupled by a second cross tie and configured diagonally to the first pair of wheels. A shock absorber may be coupled to both cross ties to link all wheels together, for full distribution of all loads across all wheels.

A damping force control device 10 comprises vary damping shock absorbers, a detector, and a controller. Each of the shock absorbers sets damping coefficient from a minimum value to a maximum value in order to adjust damping force. The detector detects vertical vibration state quantity relating to vibration of the sprung mass. The controller performs an ordinary control for setting the damping coefficient based on the vertical vibration state quantity and according to a predetermined control law suitable for an assumption that all of the wheels touch ground. The controller performs, when at least one of the wheels is an ungrounded wheel which does not touch the ground and each of the other wheels is a grounded wheel which touches the ground, a specific control for setting the damping coefficient of the shock absorber corresponding to the grounded wheel to a first specific value greater than the minimum value.

A suspension apparatus includes a pair of hydraulic cylinders and a valve device provided between an upper chamber and a lower chamber of each of the hydraulic cylinders and configured to establish and block communication between these chambers. The valve device includes a first passage and an extension-side damping force generation mechanism. Hydraulic oil flows out from the upper chamber into the first passage due to movement of a piston in a cylinder of the hydraulic cylinder. The extension-side damping force generation mechanism includes a damping valve and a back-pressure chamber. The damping valve is disposed in the first passage and generates a damping force by restricting a flow of the hydraulic oil generated due to a sliding movement of the piston. The back-pressure chamber applies an inner pressure thereof to the damping valve in a valve-closing direction.

A suspension apparatus includes a valve device provided between an upper chamber and a lower chamber of each of hydraulic cylinders and configured to establish and block communication between these chambers. The valve device includes a first passage and an extension-side damping force generation mechanism. Hydraulic oil flows out from the upper chamber into the first passage due to a movement of a piston in a cylinder of each of the hydraulic cylinders. The extension-side damping force generation mechanism includes a damping valve and a back-pressure chamber. The damping valve is disposed in the first passage, and generates a damping force by restricting a flow of the hydraulic oil generated due to a sliding movement of the piston. The back-pressure chamber applies an inner pressure thereof to this damping valve in a valve-closing direction.

Cross-linked vehicle suspension systems are disclosed. A first wheel is mechanically linked to a second wheel by a cross tie, so that motion from an impact with an obstacle by the first wheel is transmitted to the second wheel. A shock absorber may be coupled to each wheel, the cross tie, or both, to distribute absorption of the impact. In some embodiments, a second pair of wheels may be coupled by a second cross tie and configured diagonally to the first pair of wheels. A shock absorber may be coupled to both cross ties to link all wheels together, for full distribution of all loads across all wheels.

A suspension control system dynamically adjusts pistons located proximal to wheels of an agricultural machine to substantially equalize distribution of weight of the machine at each wheel and/or provide a substantially constant desired orientation of the machine above a ground surface thereby protecting laterally extending sprayer booms from contacting the ground. Articulation, pitch, roll and/or machine height can be determined from piston measurements on the machine to apply such height corrections. For sprayers, this allows controlling clearance and suspension height to maintain the boom parallel to the ground to prevent damage.