A device, which is autonomous or which can be associated with another structure, for propulsion in a liquid environment, is described. The device has a bladder body made of a soft material, developing along and around a central longitudinal axis, defining an internal chamber between a dorsal wall and a ventral wall; in the bladder body, an inlet opening and an outlet opening of a liquid in and out of the chamber, arranged at a longitudinal end of the body; and drive means for driving a contraction of the bladder, arranged on the dorsal wall and having a mechanical connection with the ventral to cyclically attract the ventral wall to the dorsal wall, thereby causing a pulsed ejection of a propeller jet from the chamber through the outlet opening.

A blade for cycloidal rotor or propeller is provided with means to dynamically change within each revolution: its relative pivot point location along chord, extend or retract trailing edge, make actuated or passive turns of trailing edge flap, dynamically control stiffness of at least the flexible trailing edge, open or close strips covering much of blade surface area to allow flow through the blade. These features will enable the control system to continually adjust each blade to its immediate operating environment along the orbit.

A blade for cycloidal rotor or propeller is provided with means to dynamically change within each revolution: its relative pivot point location along chord, extend or retract trailing edge, make actuated or passive turns of trailing edge flap, dynamically control stiffness of at least the flexible trailing edge, open or close strips covering much of blade surface area to allow flow through the blade. These features will enable the control system to continually adjust each blade to its immediate operating environment along the orbit.

Disclosed herein are permanent magnetic AC machine direct-drive resonant flapper system for flapping wing micro air vehicles and flapping fin autonomous underwater vehicles.

A control system for a trolling motor operated based upon commands generated by a wireless remote control device and a wired foot pedal is provided. The controller is interposed between the trolling motor and the wired foot pedal to add wireless controllability to the trolling motor via the wireless remote control. The controller communicates with the remote control through a bidirectional wireless communication link to receive commands and to provide status information on the operation of the motor. The remote control includes user inputs for generating commands that are sent wirelessly to the controller to control operation of the marine device. The remote control also includes a display for displaying real time status information that is received wirelessly from the controller. The controller generates control signals upon receipt of wireless communication from the remote control that simulate signals that are normally generated by the wired foot pedal.

A control system for a trolling motor operated based upon commands generated by a wireless remote control device and a wired foot pedal is provided. The controller is interposed between the trolling motor and the wired foot pedal to add wireless controllability to the trolling motor via the wireless remote control. The controller communicates with the remote control through a bidirectional wireless communication link to receive commands and to provide status information on the operation of the motor. The remote control includes user inputs for generating commands that are sent wirelessly to the controller to control operation of the marine device. The remote control also includes a display for displaying real time status information that is received wirelessly from the controller. The controller generates control signals upon receipt of wireless communication from the remote control that simulate signals that are normally generated by the wired foot pedal.

A method of de-spinning a rotor of a propulsion system includes providing one or more spinning rotors rotatably mounted on a frame with a bearing having a bearing outer race, bearing balls, and bearing inner race; providing a force mechanism coupled with the one or more spinning rotors for applying a load to the one or more spinning rotors; and loading an outer portion of the outer bearing race, bearing ball, and inner bearing race of the bearing, a load on the outer portion of the bearing race, bearing ball, and inner bearing race of the bearing corresponding to a force applied to the one or more spinning rotors by the drive mechanism. The one or more spinning rotors de-spin at a rate corresponding to the load on the bearing balls.

Provided is a mobile water quality monitoring platform for a fishpond, belonging to the technical field of water quality monitoring devices. The mobile water quality monitoring platform for a fishpond includes a floating body, a first rotating shaft and a second rotating shaft are disposed on the floating body, the first rotating shaft is rotatably disposed on the floating body through two first support plates, two second support plates are vertically disposed on the floating body, an elongated chute hole is horizontally disposed on two second support plates respectively, both ends of the second rotating shaft are inserted into two chute holes respectively, the first rotating shaft and the second rotating shaft are connected through a connecting rod mechanism, a driving mechanism that enables the first rotating shaft and the second rotating shaft to rotate simultaneously is disposed on the connecting rod mechanism.

Provided is a mobile water quality monitoring platform for a fishpond, belonging to the technical field of water quality monitoring devices. The mobile water quality monitoring platform for a fishpond includes a floating body, a first rotating shaft and a second rotating shaft are disposed on the floating body, the first rotating shaft is rotatably disposed on the floating body through two first support plates, two second support plates are vertically disposed on the floating body, an elongated chute hole is horizontally disposed on two second support plates respectively, both ends of the second rotating shaft are inserted into two chute holes respectively, the first rotating shaft and the second rotating shaft are connected through a connecting rod mechanism, a driving mechanism that enables the first rotating shaft and the second rotating shaft to rotate simultaneously is disposed on the connecting rod mechanism.

A propulsion method includes: providing a pair of synchronized rotors rotatably mounted on a frame with a bearing having a bearing outer race, bearing balls, and bearing inner race; providing a plurality of permanent magnets mounted on the pair of synchronized rotors; rotating the pair of synchronized rotors such that one of the pair of synchronized rotors rotates in a clockwise direction and the other of the pair of synchronized rotors rotates in a counterclockwise direction; loading an outer portion of the outer bearing race, bearing ball, and inner bearing race of each of the bearings, a load on the outer portion of the bearings corresponding to an attractive force between the permanent magnets of the pair of synchronized rotors. A thrust is imparted on the frame in a direction corresponding to a direction of loading of the inner bearing race.