Personal watercraft for amplifying manual rowing or paddling with propulsion

1. A powered watercraft system for a user comprising:

a watercraft body;

a propulsion system;

a sensor configured to measure a value indicative of a time-variable first propulsive force acting on the watercraft body resulting from an engagement by arm motion of the user with water at a side of the watercraft body; and

a controller configured control the propulsion system to generate a second propulsive force for powering the watercraft body based on the value indicative of the first propulsive force, the generated second propulsive force being at least partially contemporary with the first propulsive force.

2. The powered watercraft according to claim 1 , wherein the controller is configured to process the value indicative of the first propulsive thrust to generate a set value for the propulsion system to generate the second propulsive force to be substantially proportional to a factor k to the first propulsive force.

3. The powered watercraft according to claim 1 , wherein the sensor is external to the watercraft body and the propulsion system, and is operatively connected to the controller in a wireless or wired fashion.

4. The powered watercraft according to claim 3 , wherein the sensor includes a bending measurement device operatively attached to a paddling device operated by the arm motion of the user, and the value indicative of the first propulsive force is based on a bending of at least a part of the paddling device.

5. The powered watercraft according to claim 3 , wherein the sensor includes a flow meter operatively attached to a paddling device operated by the arm motion of the user, and the value indicative of the first propulsive force is based on a water flow measured by the flow meter.

6. The powered watercraft according to claim 1 , wherein the sensor includes an accelerometer arranged at the watercraft body, and the value indicative of the first propulsive force is based on an acceleration of the watercraft body caused by the first propulsive force.

7. A powered watercraft for a user comprising:

a watercraft body;

a propulsion system;

a device for receiving a value indicative of a time-variable first propulsive force acting on the watercraft body resulting from an engagement by arm motion of the user with water at a side of the watercraft body; and

a controller for controlling the propulsion system to generate a second propulsive force for powering the watercraft body based on the value indicative of the first propulsive force, the generated second propulsive force being at least partially contemporary with the first propulsive force.

8. The powered watercraft according to claim 7 , wherein the device for receiving receives wireless data or wired data from a sensor external to the powered watercraft that generates the value indicative of the first propulsive force.

9. The powered watercraft according to claim 7 , wherein the device for receiving receives wired data from a sensor arranged on the watercraft body that generates the value indicative of the first propulsive force.

10. The powered watercraft according to claim 7 , wherein the controller is configured to process the value indicative of the first propulsive thrust to generate a set value for the propulsion system to generate the second propulsive force to be substantially proportional to a factor k to the first propulsive force.

11. A propulsion container for attachment to a personal watercraft for a user, the container comprising:

a propulsion system;

a device for receiving a value indicative of a time-variable first propulsive force acting on the personal watercraft resulting from an engagement by arm motion of the user with water at a side of the personal watercraft; and

a controller for controlling the propulsion system to generate a second propulsive force for powering the personal watercraft based on the value indicative of the first propulsive force, the generated second propulsive force being at least partially contemporary with the first propulsive force.

12. The propulsion container according to claim 11 , wherein the controller is configured to process the value indicative of the first propulsive thrust to generate a set value for the propulsion system to generate the second propulsive force to be substantially proportional to a factor k to the first propulsive force.

13. The propulsion container according to claim 11 , further comprising:

a sensor operatively connected to the device for receiving, configured to measure the value indicative of the first propulsive force resulting from the engagement of the user by the arm motion.

14. The propulsion container according to claim 13 , wherein the sensor includes an accelerometer arranged to measure an acceleration of the propulsion container caused by the first propulsive force.

15. The powered watercraft system according to claim 1 , wherein the engagement of the user by the arm motion includes at least one of a paddling motion by direct water engagement of a hand of the user, a paddling motion caused by the arm motion with a paddle, and a rowing motion caused by the arm motion with an oar.

16. The powered watercraft according to claim 7 , wherein the engagement of the user by the arm motion includes at least one of a paddling motion by direct water engagement of a hand of the user, a paddling motion caused by the arm motion with a paddle, and a rowing motion caused by the arm motion with an oar.

17. The propulsion container according to claim 11 , wherein the engagement of the user by the arm motion includes at least one of a paddling motion by direct water engagement of a hand of the user, a paddling motion caused by the arm motion with a paddle, and a rowing motion caused by the arm motion with an oar.

18. The powered watercraft system according to claim 1 , wherein when the first propulsive force is decreasing, the controller is configured control the propulsion system to generate the second propulsive force to limit a deceleration of the watercraft body to a threshold value.

19. The powered watercraft according to claim 7 , wherein when the first propulsive force is decreasing, the controller is configured control the propulsion system to generate the second propulsive force to limit a deceleration of the watercraft body to a threshold value.

20. The propulsion container according to claim 11 , wherein when the first propulsive force is decreasing, the controller is configured control the propulsion system to generate the second propulsive force to limit a deceleration of the personal watercraft to a threshold value.