A braking system for a rollator with a frame includes an adjustable handle to be installed on a right subframe or a left subframe of the frame of the rollator, a bracket fixedly connected to the handle, a lever rotatably connected to the bracket, a lock movably connected to the bracket and configured to fix the lever in a locked position when the lock is moved relative to the bracket once the lever is rotated toward the frame, and a wire operably connected between the lever and a brake on the frame of the rollator, such that the wire applies the brake when the lever is rotated toward the bracket and when the lever is fixed in the locked position.

A mobile walking aid includes an undercarriage, a frame and a support for a person's leg. The undercarriage comprises a two-wheeled front axle and a rear axle. The rear axle can be converted between a single-wheeled version with a first wheel, and a two-wheeled version. In order to convert from the single-wheeled version to the two-wheeled version, a conversion kit can be provided which comprises an axle extension that can be mounted on the axle of the first wheel, and a second wheel. The axle extension can be mounted, optionally, on both sides of the axle of the first wheel which is arranged laterally and centrally between the front wheels.

A mobile walking aid includes an undercarriage, a frame and a support for a person's leg. The undercarriage comprises a two-wheeled front axle and a rear axle. The rear axle can be converted between a single-wheeled version with a first wheel, and a two-wheeled version. In order to convert from the single-wheeled version to the two-wheeled version, a conversion kit can be provided which comprises an axle extension that can be mounted on the axle of the first wheel, and a second wheel. The axle extension can be mounted, optionally, on both sides of the axle of the first wheel which is arranged laterally and centrally between the front wheels.

A knee walker with four-wheel steering. The knee walker includes a frame, at least one front axle assembly, at least one rear axle assembly, a kneeling pad assembly, and a steering system. The steering system is configured to turn the rear axle assembly in the opposite direction from the front axle assembly. The opposing angles of the front and rear wheels enable the knee walker to perform tighter turns by eliminating rear wheel drag.

A knee walker with four-wheel steering. The knee walker includes a frame, at least one front axle assembly, at least one rear axle assembly, a kneeling pad assembly, and a steering system. The steering system is configured to turn the rear axle assembly in the opposite direction from the front axle assembly. The opposing angles of the front and rear wheels enable the knee walker to perform tighter turns by eliminating rear wheel drag.

A vehicle comprising: a front wheel set and a rear wheel set, each set comprising two wheels and an axle attached to the said wheels; a base structure or chassis; a front elastic pivot structure, connecting the front wheel set to the chassis, wherein said front elastic pivot structure comprises a front set of at least one elastic joint, enabling the chassis to tilt along a front roll axis in respect to the said front wheel set; a front shock absorber, associated with the front wheel set; a rear elastic pivot structure, associated with the rear wheel set, wherein said rear elastic pivot structure comprises a rear set of at least one elastic joint, enabling the chassis to tilt along a rear roll axis in respect to the said rear wheel set; and a rear shock absorber, associated with the rear wheel set.

A vehicle comprising: a front wheel set and a rear wheel set, each set comprising two wheels and an axle attached to the said wheels; a base structure or chassis; a front elastic pivot structure, connecting the front wheel set to the chassis, wherein said front elastic pivot structure comprises a front set of at least one elastic joint, enabling the chassis to tilt along a front roll axis in respect to the said front wheel set; a front shock absorber, associated with the front wheel set; a rear elastic pivot structure, associated with the rear wheel set, wherein said rear elastic pivot structure comprises a rear set of at least one elastic joint, enabling the chassis to tilt along a rear roll axis in respect to the said rear wheel set; and a rear shock absorber, associated with the rear wheel set.

A knee walker with four-wheel steering. The knee walker includes a frame, at least one front axle assembly, at least one rear axle assembly, a kneeling pad assembly, and a steering system. The steering system is configured to turn the rear axle assembly in the opposite direction from the front axle assembly. The opposing angles of the front and rear wheels enable the knee walker to perform tighter turns by eliminating rear wheel drag.

A knee walker with four-wheel steering. The knee walker includes a frame, at least one front axle assembly, at least one rear axle assembly, a kneeling pad assembly, and a steering system. The steering system is configured to turn the rear axle assembly in the opposite direction from the front axle assembly. The opposing angles of the front and rear wheels enable the knee walker to perform tighter turns by eliminating rear wheel drag.

A mobility device that can accommodate speed sensitive steering, adaptive speed control, a wide weight range of users, an abrupt change in weight, traction control, active stabilization that can affect the acceleration range of the mobility device and minimize back falls, and enhanced redundancy that can affect the reliability and safety of the mobility device.