The present application is directed to a selectively deployable fin system which includes at least one housing positioned within a body of a standup paddleboard, the housing defining at least one housing passage therein, at least one actuator is positioned within the housing. The actuator is con figured to be operable by a user positioned on the standup paddleboard or similar watercraft during use. At least one linkage system, in communication with the actuator, is positioned within the housing. In addition, at least one fin is in communication with the actuator via the linkage device. The fin is configured to be selectively positioned within the housing in a retracted configuration and selectively extending from the housing in a deployed configuration.

The present application is directed to a selectively deployable fin system which includes at least one housing positioned within a body of a standup paddleboard, the housing defining at least one housing passage therein, at least one actuator is positioned within the housing. The actuator is con figured to be operable by a user positioned on the standup paddleboard or similar watercraft during use. At least one linkage system, in communication with the actuator, is positioned within the housing. In addition, at least one fin is in communication with the actuator via the linkage device. The fin is configured to be selectively positioned within the housing in a retracted configuration and selectively extending from the housing in a deployed configuration.

Stirling cycle machine. The machine includes at least one rocking drive mechanism which includes: a rocking beam having a rocker pivot, at least one cylinder and at least one piston. The piston is housed within a respective cylinder and is capable of substantially linearly reciprocating within the respective cylinder. Also, the drive mechanism includes at least one coupling assembly having a proximal end and a distal end. The linear motion of the piston is converted to rotary motion of the rocking beam. Also, a crankcase housing the rocking beam and housing a first portion of the coupling assembly is included. The machine also includes a working space housing the at least one cylinder, the at least one piston and a second portion of the coupling assembly. An airlock is included between the workspace and the crankcase and a seal is included for sealing the workspace from the airlock and crankcase. A burner and burner control system is also included for heating the machine and controlling ignition and combustion in the burner.

Stirling cycle machine. The machine includes at least one rocking drive mechanism which includes: a rocking beam having a rocker pivot, at least one cylinder and at least one piston. The piston is housed within a respective cylinder and is capable of substantially linearly reciprocating within the respective cylinder. Also, the drive mechanism includes at least one coupling assembly having a proximal end and a distal end. The linear motion of the piston is converted to rotary motion of the rocking beam. Also, a crankcase housing the rocking beam and housing a first portion of the coupling assembly is included. The machine also includes a working space housing the at least one cylinder, the at least one piston and a second portion of the coupling assembly. An airlock is included between the workspace and the crankcase and a seal is included for sealing the workspace from the airlock and crankcase. A burner and burner control system is also included for heating the machine and controlling ignition and combustion in the burner.

An actuator system having a controlled element configured for rotary movement about a first axis relative to a reference structure; a linkage system between the element and reference structure; a first actuator and a second actuator configured to power a first degree of freedom and an independent second degree of freedom of the linkage system, respectively; the linkage system having a first link configured for rotary movement about a second axis not coincident to the first axis and second link configured for rotary movement about a third axis; the linkage system configured such that a first angle of rotation may be driven independently of a second angle of rotation between said first link and said reference structure; wherein one of the first or second actuators is configured and arranged to drive rotation of the element about the first axis when the other is operatively locked.

A multi-link rotation structure is provided, including: a base; two arm assemblies, each of the two arm assemblies including a pivot portion pivoted to the base and at least two arms connected with the pivot portion and extending away from each other, the pivot portions of the two arm assemblies being non-coaxial; at least two unidirectional rotation devices, respectively axially pivoted to the at least two arms of one of the two arm assemblies, rotatable in a same direction; at least two linkage assemblies, each of the at least two linkage assemblies pivoted to the at least two arms of the other of the two arm assemblies and pivoted to one of the at least two unidirectional rotation devices.

A multi-link rotation structure is provided, including: a base; two arm assemblies, each of the two arm assemblies including a pivot portion pivoted to the base and at least two arms connected with the pivot portion and extending away from each other, the pivot portions of the two arm assemblies being non-coaxial; at least two unidirectional rotation devices, respectively axially pivoted to the at least two arms of one of the two arm assemblies, rotatable in a same direction; at least two linkage assemblies, each of the at least two linkage assemblies pivoted to the at least two arms of the other of the two arm assemblies and pivoted to one of the at least two unidirectional rotation devices.

The simultaneous actuating mechanism for parallel axis rotors includes a base and a plurality of rotating rotors mounted in spaced relation inside the base, the rotors having parallel axes of rotation. A crank pin extends from each rotor at a position offset from the corresponding axis of rotation. A driving assembly is coupled to the crank pin of all the rotors. Operation of the driving assembly causes simultaneous rotation of the rotors to facilitate various mechanical functions, such as threading, steering, and reciprocation of multiple elements.

The simultaneous actuating mechanism for parallel axis rotors includes a base and a plurality of rotating rotors mounted in spaced relation inside the base, the rotors having parallel axes of rotation. A crank pin extends from each rotor at a position offset from the corresponding axis of rotation. A driving assembly is coupled to the crank pin of all the rotors. Operation of the driving assembly causes simultaneous rotation of the rotors to facilitate various mechanical functions, such as threading, steering, and reciprocation of multiple elements.

Systems and methods for converting ordinary circular rotary motion into any non-circular motion that can be defined as a non-overlapping proper function in polar coordinates are provided. Embodiments disclosed teach how to make and use devices that can use the rotary output from motors, turbines and other sources of circular rotary motion to create motion that follows square, rectangular, triangular, or other useful paths. Such devices can be usefully employed as a replacement for conventional devices in applications where the desired path or area of coverage is not circular, including air-moving (fans), air-energy capture (turbines), surface finishing (sanding, polishing, cleaning), among many others.