Abstract: The vehicle comprises a base and a seat moveable along a curve having a focal point. The vehicle is adjustable to position an occupant in the seat to achieve a desired position for the center of gravity of the occupant relative to the focal point of the curve. A method for minimizing effort required to tilt the seat of a personal mobility vehicle comprises the steps of providing a personal mobility vehicle having a seat that is adapted to move along an arc having a center of curvature, positioning the seat substantially horizontally, providing an occupant in the seat, and adjusting the position of the vehicle occupant's center of gravity so that the center of gravity is substantially equal to or below the center of curvature of the arc.

Abstract: A center-of-gravity tilt-in-space wheelchair includes a base, a seat for supporting an occupant, and tracks supporting the seat for selective seat movement relative to the base. Wheels are adapted to support the base relative to a supporting surface. The tracks serve as rolling or sliding surfaces that allow the seat to rotate with respect to the base. Each track has a constant-radius arc with a focal point that is adapted to be coincident with the center of gravity of the wheelchair occupant. A low-friction supports the base relative to the seat. The low-friction support may include low friction elements that mate with the tracks to support for the tracks. The support can be adjustable to permit the overall tilt angle range of the tracks to be adjusted. The wheelchair seat can be adjusted to maintain the focal point of the constant-radius arc of the tracks coincident with the center of gravity of the wheelchair occupant. The front and rear wheels can be adjusted fore and aft relative to the focal point.

Abstract: The vehicle comprises a base and a seat moveable along a curve having a focal point. The vehicle is adjustable to position an occupant in the seat to achieve a desired position for the center of gravity of the occupant relative to the focal point of the curve. A method for minimizing effort required to tilt the seat of a personal mobility vehicle comprises the steps of providing a personal mobility vehicle having a seat that is adapted to move along an arc having a center of curvature, positioning the seat substantially horizontally, providing an occupant in the seat, and adjusting the position of the vehicle occupant's center of gravity so that the center of gravity is substantially equal to or below the center of curvature of the arc.

Abstract: A center-of-gravity tilt-in-space wheelchair includes a base, a seat for supporting an occupant, and tracks supporting the seat for selective seat movement relative to the base. Wheels are adapted to support the base relative to a supporting surface. The tracks serve as rolling or sliding surfaces that allow the seat to rotate with respect to the base. Each track has a constant-radius arc with a focal point that is adapted to be coincident with the center of gravity of the wheelchair occupant. A low-friction supports the base relative to the seat. The low-friction support may include low friction elements that mate with the tracks to support for the tracks. The support can be adjustable to permit the overall tilt angle range of the tracks to be adjusted. The wheelchair seat can be adjusted to maintain the focal point of the constant-radius arc of the tracks coincident with the center of gravity of the wheelchair occupant. The front and rear wheels can be adjusted fore and aft relative to the focal point.