Wheeled vehicles, such as wheelchairs, that are adapted to traverse obstacles are provided. The wheeled vehicles include a frame, drive wheels, front anti-tip wheels positioned in front of the drive wheels and rear anti-tip wheels positioned behind the drive wheels. One exemplary vehicle includes front anti-tip wheels supported by rigid arms that are fixed to the frame and drive assemblies that are independently suspended from the frame. Another exemplary vehicle includes a linkage that links the front and rear anti-tip wheels, such that movement of one of the front or rear anti-tip wheel relative to the frame causes movement of the other wheel relative to the frame.

A vehicle includes a vehicle body frame, a vehicle body tilt sensor, a drive unit, and a seat. The vehicle body tilt sensor is provided at the vehicle body frame and detects a tilt angle of the vehicle body frame. The drive unit is coupled to the vehicle body frame and moves the vehicle body frame by inverted pendulum control based on the tilt angle detected by the vehicle body tilt sensor. The seat includes a seat body and a leg part. The seat is capable of being raised and lowered between a low position at which the leg part is in contact with a floor surface and a high position at which the leg part separates from the floor surface, and the seat is elastically coupled to the vehicle body frame. A seat tilt sensor which detects a tilt angle of the seat is provided at the seat.

A wheelchair suspension comprises a frame, at least one pivot arm, at least one front caster, at least one rear caster, a stabilizing system, and a sensor. The pivot arm is coupled to the frame. The front caster is coupled to the pivot arm. The rear caster is coupled to the frame. The stabilizing system is coupled to the frame and the pivot arm. The sensor is arranged such that tipping of the frame causes actuation of the stabilizing system to at least partially resist further movement of the frame.

A mobility vehicle may comprise a frame, a first pivot arm, a second pivot arm, and a suspension assembly. The first pivot arm may be coupled to the frame and coupled to a drive wheel. The second pivot arm may be coupled to the frame and coupled to a ground engaging caster wheel. The suspension assembly may be coupled to the frame. The suspension assembly may include a first spring assembly and a second spring assembly. The first spring assembly may be disposed about a first spring axis and coupled to the first pivot arm. The second spring assembly may be disposed about a second spring axis and coupled to the second pivot arm. The first spring axis and the second spring axis may be disposed relative to each other at an angle of no greater than about 150° when the mobility vehicle is operating on horizontal ground.

A propulsion system for a manual wheelchair includes a mounting clamp and a propulsion drive unit having a drive wheel assembly and a support suspension. The support suspension is configured to provide linear movement of the drive wheel and drive hub assembly relative to the manual wheelchair. The support suspension includes a linear bearing and slide member assembly having at least one linear bearing and a slide member for accommodating the linear movement of the drive wheel assembly and further includes a resilient suspension member that provides a tractive effort force to the drive wheel. The drive wheel assembly is supported on a carriage that is attached to one of the at least one linear bearing or the slide member and a mounting block is attached to the other. The mounting block has a clamp interface with a locating tab that engages a corresponding mounting slot in the mounting clamp.

A mobility vehicle may comprise a frame, a first pivot arm, a second pivot arm, and a suspension assembly. The first pivot arm may be coupled to the frame and coupled to a drive wheel. The second pivot arm may be coupled to the frame and coupled to a ground engaging caster wheel. The suspension assembly may be coupled to the frame. The suspension assembly may include a first spring assembly and a second spring assembly. The first spring assembly may be disposed about a first spring axis and coupled to the first pivot arm. The second spring assembly may be disposed about a second spring axis and coupled to the second pivot arm. The first spring axis and the second spring axis may be disposed relative to each other at an angle of no greater than about 150° when the mobility vehicle is operating on horizontal ground.

Embodiments of a suspension for a vehicle is provided. The suspension includes, for example, a frame and a locking assembly. The locking assembly inhibits tipping of a frame of the vehicle when tipping of the frame is detected.

Wheeled vehicles, such as wheelchairs, that are adapted to traverse obstacles are provided. The wheeled vehicles include a frame, drive wheels, front anti-tip wheels positioned in front of the drive wheels and rear anti-tip wheels positioned behind the drive wheels. One exemplary vehicle includes front anti-tip wheels supported by rigid arms that are fixed to the frame and drive assemblies that are independently suspended from the frame. Another exemplary vehicle includes a linkage that links the front and rear anti-tip wheels, such that movement of one of the front or rear anti-tip wheel relative to the frame causes movement of the other wheel relative to the frame.

A selectively locking rotational bearing element includes at least one bearing element supporting an outer race for rotational movement and a plurality of locking elements disposed circumferentially about an inner surface of the outer race. An actuator selectively moves the plurality of locking elements into engagement with the outer race to restrict rotational movement of the outer race and selectively move the plurality of locking elements away from engagement with the outer race such that the outer race is free to rotate relative to the locking elements.

A multi-functional off-road vehicle has a frame which includes a left lateral frame member and a right lateral frame member. The two frame members are connected by a crossbar. Four wheel assemblies are connected to the frame. At least two of the wheel assemblies are continuous tracks. The crossbar includes a track width adjustment actuator which extends and contracts a length of the crossbar and thereby changes a track width of the vehicle.