Abstract: A chassis for a tracked mobility device may include: a battery box floor; a battery box rear wall; a pair of main side rails; a main front cross member; a lower box rear cross member; a pair of side bogie support tubes; a pair of motor support tubes; rear side support tubes; front side support tubes; a pair of bogie support plates; short bogie cross tubes; seat frame plates; a tensioner support frame; a rear cross support plate; motor/gear boxes having floors, rear walls, outer side walls, inner side walls, and outer side wall extensions/gussets; anti-tip tubes; anti-tip cross-members; and anti-tip vertical tie rods. The chassis components may be welded together to provide a rigid, stable, unitary construction.

Abstract: A tracked mobility device includes a pair of track drives having a rear weight-bearing wheel assembly, a center weight-bearing wheel assembly, a forward weight-bearing wheel assembly, and a front roller assembly. The rear weight-bearing wheels, the center weight-bearing wheels, and the forward weight-bearing wheels are fixed to the frame at a height effective to cause the main weight-bearing surface to always have a “V”-shaped lower surface when viewed from the side. The center weight-bearing wheels, the forward weight-bearing wheels, and the front rollers are fixed to the frame at a height effective to cause that portion of each track drive always to have a “V”-shaped lower surface when viewed from the side. At least one powered drive wheel is provided, and at least one of the rollers is a tensioning roller.

Abstract: A tracked mobility device includes a pair of track drives having a rear weight-bearing wheel assembly, a center weight-bearing wheel assembly, a forward weight-bearing wheel assembly, and a front roller assembly. The rear weight-bearing wheels, the center weight-bearing wheels, and the forward weight-bearing wheels are fixed to the frame at a height effective to cause the main weight-bearing surface to always have a “V”-shaped lower surface when viewed from the side. The center weight-bearing wheels, the forward weight-bearing wheels, and the front rollers are fixed to the frame at a height effective to cause that portion of each track drive always to have a “V”-shaped lower surface when viewed from the side. At least one powered drive wheel is provided, and at least one of the rollers is a tensioning roller.

Abstract: A tracked mobility device includes: a) a frame supporting a seat; b) a pair of track drives connected to the frame, with each track drive including a powered center drive wheel, a front roller, a rear roller, and a flexible track, with the center drive wheel having a diameter that is at least 50% greater than the diameter of either the front roller or the rear roller, and c) a rear wheel assembly connected to the frame, with the rear wheel assembly having three wheels sharing a common axle, with the diameter of the center rear wheel being at least 10% larger than the diameter of the two outer rear wheels; d) a source of power to power said center drive wheels; and e) a controller effective for controlling the speed and direction of rotation of each of the track drives.

Abstract: A tracked mobility device includes a frame, a pair of track drives connected to the frame, and a rear wheel assembly that is independent of the track drives. Each track drive has a flexible track rotating around a set of wheels, with each set of wheels including a rear powered wheel, a central weight-bearing wheel, and a front roller wheel. The wheels are fixed to the frame at a height effective to cause the track drive always to have a “V”-shaped lower surface when viewed from the side. The independent rear wheel is at a fixed and constant height with respect to the frame, with the fixed and constant height being effective to allow the rear wheel to cooperate with the lowered central portion of each of said track drives to provide a three-point contact with a flat surface.

Abstract: A tracked mobility device includes: a) a frame supporting a seat; b) a pair of track drives connected to the frame, with each track drive including a powered center drive wheel, a front roller, a rear roller, and a flexible track, with the center drive wheel having a diameter that is at least 50% greater than the diameter of either the front roller or the rear roller, and c) a rear wheel assembly connected to the frame, with the rear wheel assembly having three wheels sharing a common axle, with the diameter of the center rear wheel being at least 10% larger than the diameter of the two outer rear wheels; d) a source of power to power said center drive wheels; and e) a controller effective for controlling the speed and direction of rotation of each of the track drives.

Abstract: A tracked mobility device includes: a) a pair of independent, self-supported track drives defining a planar ground contact area; b) a multi-directional wheel having a raised position above the plane of the ground contact area, and a lowered position below the plane of the ground contact area; and c) an actuator for moving the multi-directional wheel to either its raised or its lowered position. When the actuator lowers the multi-directional wheel, part of the planar ground contact area is raised from the ground without raising all of the planar ground contact area from the ground. Each track drive functions independently so that bumps along one track may be traversed without tilting the entire vehicle. Each track drive may be attached to the vehicle body with flexible mounts that allow each track drive to independently tilt upward or downward as the device moves on its tracks.

Abstract: A tracked mobility device includes: a) a pair of independent, self-supported track drives defining a planar ground contact area; b) a multi-directional wheel having a raised position above the plane of the ground contact area, and a lowered position below the plane of the ground contact area; and c) an actuator for moving the multi-directional wheel to either its raised or its lowered position. When the actuator lowers the multi-directional wheel, part of the planar ground contact area is raised from the ground without raising all of the planar ground contact area from the ground. Each track drive functions independently so that bumps along one track may be traversed without tilting the entire vehicle. Each track drive may be attached to the vehicle body with flexible mounts that allow each track drive to independently tilt upward or downward as the device moves on its tracks.