A modular chassis is provided for an off-road vehicle to improve assembly, servicing, and repairing of a drivetrain of the off-road vehicle. The modular chassis includes a chassis to support components of the off-road vehicle. A front frame module couples with a front of the chassis, and a rear frame module couples with a rear of the chassis. The front frame module supports lower suspension arms of the off-road vehicle by way of inboard bushing joints. The front frame module supports at least a steering gear and a front differential of the off-road vehicle. The rear frame module is a tube-frame structure that supports components of the off-road vehicle. A lower portion of the rear frame module extends rearward and acutely upward to a top frame member that couples with upper side portions of the chassis. Several cross-members impart structural integrity to the rear frame module.

A modular chassis is provided for an off-road vehicle to improve assembly, servicing, and repairing of a drivetrain of the off-road vehicle. The modular chassis includes a chassis to support components of the off-road vehicle. A front frame module couples with a front of the chassis, and a rear frame module couples with a rear of the chassis. The front frame module supports lower suspension arms of the off-road vehicle by way of inboard bushing joints. The front frame module supports at least a steering gear and a front differential of the off-road vehicle. The rear frame module is a tube-frame structure that supports components of the off-road vehicle. A lower portion of the rear frame module extends rearward and acutely upward to a top frame member that couples with upper side portions of the chassis. Several cross-members impart structural integrity to the rear frame module.

A wheel suspension system is disclosed. The wheel suspension system may include a suspension assembly that may include a sub-frame adapted to be connected to a reference frame of a vehicle, a wheel interface adapted to rotatably support a wheel of the vehicle and to define a wheel rotation axis and a wheel rotation plane, and one or more linking units. Components of the linking unit(s) may be pivotally connected to each other, to sub-frame and to the wheel interface using pivoting connection that may cause components of the linking unit(s) to rotate about axes that are substantially perpendicular to the wheel rotation axis. The components of the linking unit(s) may be dimensioned, and positions of the pivoting connections may be set to cause a substantially linear motion of the wheel interface along a reference wheel interface motion axis that is perpendicular to the wheel rotation axis.

A wheel suspension system is disclosed. The wheel suspension system may include a suspension assembly that may include a sub-frame adapted to be connected to a reference frame of a vehicle, a wheel interface adapted to rotatably support a wheel of the vehicle and to define a wheel rotation axis and a wheel rotation plane, and one or more linking units. Components of the linking unit(s) may be pivotally connected to each other, to sub-frame and to the wheel interface using pivoting connection that may cause components of the linking unit(s) to rotate about axes that are substantially perpendicular to the wheel rotation axis. The components of the linking unit(s) may be dimensioned, and positions of the pivoting connections may be set to cause a substantially linear motion of the wheel interface along a reference wheel interface motion axis that is perpendicular to the wheel rotation axis.

Steer-by-wire steering systems for vehicles and related methods are described herein. An example steer-by-wire steering system includes a steering wheel angle sensor to detect a current steering wheel angle (α) of a steering wheel of the motor vehicle, a steering actuator to generate a variable steering torque on a steerable wheel of the motor vehicle, a steering angle sensor to detect a current steering angle (β) of the steerable wheel, and a steer-by-wire controller to process signals from the steering wheel angle sensor and the steering angle sensor and control the steering actuator based on the signals. The steer-by-wire controller is configured to vary a transmission ratio between a change in the steering wheel angle (α) and a change in the steering angle (β).

A universal axle-hub assembly is provided for an off-road vehicle. The universal axle-hub assembly comprises a wheel hub that receives a constant velocity (CV) axle snout into an opening extending through an axle support of the wheel hub. An outboard-most portion of the opening is a splined portion that engages with similar splines disposed on an outboard-most portion of the CV axle snout. An inboard-most portion of the opening is a smooth portion that receives a smooth portion of the CV axle snout. The axle support extends through an entirety of the width of a bearing that supports the wheel hub, such that the bearing supports the smooth portion of the CV axle snout and substantially eliminates shear forces acting on the splined portion of the CV axle snout. A bearing carrier supports the bearing and may be fastened onto a trailing arm or a spindle of the off-road vehicle.

A universal axle-hub assembly is provided for an off-road vehicle. The universal axle-hub assembly comprises a wheel hub that receives a constant velocity (CV) axle snout into an opening extending through an axle support of the wheel hub. An outboard-most portion of the opening is a splined portion that engages with similar splines disposed on an outboard-most portion of the CV axle snout. An inboard-most portion of the opening is a smooth portion that receives a smooth portion of the CV axle snout. The axle support extends through an entirety of the width of a bearing that supports the wheel hub, such that the bearing supports the smooth portion of the CV axle snout and substantially eliminates shear forces acting on the splined portion of the CV axle snout. A bearing carrier supports the bearing and may be fastened onto a trailing arm or a spindle of the off-road vehicle.

A wheel suspension system is disclosed. The wheel suspension system may include a suspension assembly that may include a sub-frame adapted to be connected to a reference frame of a vehicle, a wheel interface adapted to rotatably support a wheel of the vehicle and to define a wheel rotation axis and a wheel rotation plane, and one or more linking units. Components of the linking unit(s) may be pivotally connected to each other, to sub-frame and to the wheel interface using pivoting connection that may cause components of the linking unit(s) to rotate about axes that are substantially perpendicular to the wheel rotation axis. The components of the linking unit(s) may be dimensioned, and positions of the pivoting connections may be set to cause a substantially linear motion of the wheel interface along a reference wheel interface motion axis that is perpendicular to the wheel rotation axis.

A wheel suspension system is disclosed. The wheel suspension system may include a suspension assembly that may include a sub-frame adapted to be connected to a reference frame of a vehicle, a wheel interface adapted to rotatably support a wheel of the vehicle and to define a wheel rotation axis and a wheel rotation plane, and one or more linking units. Components of the linking unit(s) may be pivotally connected to each other, to sub-frame and to the wheel interface using pivoting connection that may cause components of the linking unit(s) to rotate about axes that are substantially perpendicular to the wheel rotation axis. The components of the linking unit(s) may be dimensioned, and positions of the pivoting connections may be set to cause a substantially linear motion of the wheel interface along a reference wheel interface motion axis that is perpendicular to the wheel rotation axis.

A wheel suspension system is disclosed. The wheel suspension system may include a suspension assembly that may include a sub-frame adapted to be connected to a reference frame of a vehicle, a wheel interface adapted to rotatably support a wheel of the vehicle and to define a wheel rotation axis and a wheel rotation plane, and one or more linking units. Components of the linking unit(s) may be pivotally connected to each other, to sub-frame and to the wheel interface using pivoting connection that may cause components of the linking unit(s) to rotate about axes that are substantially perpendicular to the wheel rotation axis. The components of the linking unit(s) may be dimensioned, and positions of the pivoting connections may be set to cause a substantially linear motion of the wheel interface along a reference wheel interface motion axis that is perpendicular to the wheel rotation axis.