A torque fluctuation absorber includes a first outer helical spline, an intermediate member, an outer member, a first spring, and a second spring. The first outer helical spline is rotatable integrally with a torque transmission shaft. The intermediate member is able to move in a first axial direction and in a second axial direction. The intermediate member is linked with the torque transmission shaft through a first helical spline coupling including the first outer helical spline. Axial movement of the outer member with respect to the torque transmission shaft is regulated. The outer member is linked with the intermediate member through a second helical spline coupling. The first spring biases the intermediate member in the first axial direction. The second spring biases the intermediate member in the second axial direction.

A propeller includes a bushing that rotates together with the propeller shaft, and a propeller damper disposed around the bushing, and an inner cylinder that surrounds the bushing via the propeller damper. The bushing includes a first cylindrical portion surrounding the propeller shaft, and a first protrusion protruding outward from the first cylindrical portion and integral with the first cylindrical portion. The inner cylinder includes a second cylindrical portion surrounding the bushing via the propeller damper and a second protrusion protruding inward from the second cylindrical portion. The inner cylinder is rotatable with respect to the bushing between a noncontact position and a contact position.

A system for rotating an inner propeller shaft within a gearcase via a driveshaft. The system includes a stub shaft that extends between forward and aft ends and is rotatable within the gearcase. A forward gear is rotatably coupled to the stub shaft, where the forward gear meshes with the driveshaft and is engageable to become rotatably fixed to the stub shaft such that rotating the driveshaft rotates the stub shaft. A shock absorbing coupler is positioned within the gearcase, where the coupler has forward and aft ends, where the forward end of the coupler is engageable with the aft end of the stub shaft, and where the aft end of the coupler engageable with the inner propeller shaft. The coupler is torsional between the forward and aft ends such that shock is absorbable between the inner propeller shaft and the driveshaft.

A field configurable autonomous vehicle includes modular elements and attachable components. The vehicle can be assembled from these modular elements and components to meet desired mission and performance characteristics without the need to purchase specially designed vehicles for each mission. The main body of the vehicle is a spherical body.

Marine propellers for coupling to a propeller drive shaft may include a propeller hub. A plurality of propeller blades may extend from the propeller hub. A shearable drive assembly may include a drive core. The drive core may include a drive core wall configured to be drivingly engaged by the propeller drive shaft. At least one drive rib may extend from the drive core wall. At least one shear cavity may be provided in the at least one drive rib. A drive sleeve may be drivingly engaged for rotation by the drive core and configured to drivingly engage the propeller hub of the marine propeller for rotation. The drive sleeve may have at least one rib slot receiving the at least one drive rib of the drive core. Other marine propellers with shearable drive assemblies are also disclosed.

A field configurable vehicle includes bladders located interior of the vehicle hull walls. One or more of the bladders can be filled with fluids of varying densities to manage the buoyancy, mass properties, and thermal heat dissipation of the vehicle.

A propeller includes a bushing, a propeller body, and a propeller damper. The bushing includes a first cylinder portion surrounding the propeller shaft and a first projection protruding outwardly in a radial direction of the propeller from an outer peripheral surface of the first cylinder portion. The propeller body includes a second cylinder portion surrounding the bushing and a second projection protruding inwardly in the radial direction from an inner peripheral surface of the second cylinder portion. The first and second projections are arranged along a rotation direction of the propeller. The propeller damper includes first and second dampers side by side along an axial direction of the propeller between the first and second cylinders. The first and second dampers are separated from each other by a separation portion, and are individually elastically deformable.

A field configurable autonomous vehicle includes modular elements and attachable components. The vehicle can be assembled from these modular elements and components to meet desired mission and performance characteristics without the need to purchase specially designed vehicles for each mission. The main body of the vehicle is a spherical body.

Damper assemblies suitable for coupling a drive to an output may include a hub for coupling to the output. The hub may include a hub drive sleeve. A drive adaptor may be configured for coupling to the drive. The drive adaptor may include an adaptor shaft disposed in the hub drive sleeve of the hub. At least one continuous circumferential damper member may encircle the adaptor shaft of the drive adaptor. The at least one circumferential damper member may be drivingly engaged by the adaptor shaft of the drive adaptor and drivingly engage the hub drive sleeve of the hub. At least one deformation space may be disposed adjacent to the at least one continuous circumferential damper member. The at least one deformation space may at least partially coincide in circumference with the at least one circumferential damper member. Marine propellers having damper assemblies are also disclosed.

A marine engine coupler for connecting a sterndrive input shaft to an engine flywheel. A splined central shaft connects the sterndrive input shaft to the coupling. Polyurethane dampers interface between the engine to the sterndrive to reduce vibration. There is a visual indicator on the coupler to allow the user to assess the integrity of the dampening material and give the user an indication that the dampening materials needs to be replaced.