Abstract: A system for performing image-guided surgery includes an instrument having a first portion configured to define a trajectory into the body of a patient, a marker device and a user-interface component. A sensing device receives electromagnetic signals that are reflected or emitted from the marker device, and a processing system, coupled to the sensing device, includes at least one processor configured with processor-executable instructions to perform operations that include tracking the position and orientation of the instrument relative to the patient based on the signals received at the sensing device, receiving a signal from the user-interface component of the instrument indicating a user-input event, and saving the trajectory into the body of the patient defined by the first portion of the instrument in response to receiving the signal.

Abstract: A watercraft propulsion system for moving a watercraft along a waterway having a bottom and a surface, wherein the watercraft presents a port side and a starboard side. The watercraft propulsion system comprises a boom assembly having a proximal end and a distal end, with the proximal end being rotatably coupled with the watercraft. The watercraft additionally comprises a wheel mounted to the distal end of the boom. The wheel includes at least one generally radially-extending blade assembly, with the blade assembly comprising a primary blade and a secondary blade. The secondary blade extends at an angle with respect to the primary blade so as to present a fluid channel between the primary blade and the secondary blade.

Abstract: A watercraft propulsion system for moving a watercraft along a waterway having a bottom and a surface, wherein the watercraft presents a port side and a starboard side. The watercraft propulsion system comprises a boom assembly having a proximal end and a distal end, with the proximal end being rotatably coupled with the watercraft. The watercraft additionally comprises a wheel mounted to the distal end of the boom. The wheel includes at least one generally radially-extending blade assembly, with the blade assembly comprising a primary blade and a secondary blade. The secondary blade extends at an angle with respect to the primary blade so as to present a fluid channel between the primary blade and the secondary blade.

Abstract: A cutterhead for cutting aquatic vegetation, includes a cutterhead shroud, stationary teeth secured to the shroud, and a drum rotatably mounted within the shroud and bearing a flight of vanes cooperating with the teeth to cut vegetation. In accordance with the non-binding aspect of the cutterhead, each vane has an edge that rises gradually from a trailing end adjacent (during drum rotation) to a stationary tooth, to provide a clearance area adjacent the vane into which a respective tooth may be deflected during cutting without impinging upon an associated vane, and thus without causing binding of the cutterhead in the event of such deflection. Each vane may have a curvilinear edge extending from its cutting end to a surface of the drum at its trailing end. The edge defines a two-dimensional profile having a trailing end tangent forming an angle of not more than 70 degrees with the drum.

Abstract: A cutterhead for cutting aquatic vegetation, includes a cutterhead shroud, stationary teeth secured to the shroud, and a drum rotatably mounted within the shroud and bearing a flight of vanes cooperating with the teeth to cut vegetation. In accordance with the non-binding aspect of the cutterhead, each vane has an edge that rises gradually from a trailing end adjacent (during drum rotation) to a stationary tooth, to provide a clearance area adjacent the vane into which a respective tooth may be deflected during cutting without impinging upon an associated vane, and thus without causing binding of the cutterhead in the event of such deflection. Each vane may have a curvilinear edge extending from its cutting end to a surface of the drum at its trailing end. The edge defines a two-dimensional profile having a trailing end tangent forming an angle of not more than 70 degrees with the drum.

Abstract: Methods and apparatus for backlit and dual-sided imaging are described. A print head array is provided comprising first and second print heads arranged along a single print head axis. The first print head is adapted to print first and second images on a substrate, and the second print head is adapted to print a coating layer between the first and second images. The coating layer may comprise a specialized printing fluid such as a layer of substantially white ink. The substrate may comprise a substantially translucent or substantially clear material.

Abstract: A printing apparatus having an array of printheads arranged along a single printhead axis, and capable of printing images and a coating layer on the substrate during a single printing operation. The coating layer can comprise a specialized printing fluid such as a layer of substantially white ink. The apparatus can perform a pre-coat printing operation, in which the coating layer is deposited first on the substrate, and the image is then printed over the coating layer. The apparatus can also perform a post-coat printing operation, in which the image is first printed onto the substrate, and the coating layer is then deposited over the image. The printhead array includes at least one printhead for printing inks to form the images, and at least one printhead for printing a specialized fluid to form the coating layer. Depending on the printing mode, a controller allocates certain nozzles of the array for printing inks and certain nozzles for printing the specialized fluid.

Abstract: Methods and apparatus for backlit and dual-sided imaging are described. A print head array is provided comprising first and second print heads arranged along a single print head axis. The first print head is adapted to print first and second images on a substrate, and the second print head is adapted to print a coating layer between the first and second images. The coating layer may comprise a specialized printing fluid such as a layer of substantially white ink. The substrate may comprise a substantially translucent or substantially clear material.