Method and system for maneuvering movable object

• US 7,366,593 B2
• Filed: 05/20/2003
• Issued: 04/29/2008
• Est. Priority Date: 05/20/2002
• Status: Active Grant

• Current Assignee: Kawasaki Jukogyo Kabushiki Kaisha
• Original Assignee: Kabushiki Kaisha Kawasaki Zosen, Kawasaki Jukogyo Kabushiki Kaisha
• Inventors: Saito, Yasuo, Ohnishi, Hiroshi, Higashi, Masaaki, Nakashima, Kenichi, Kohno, Yukinobu, Hamamatsu, Masanori, Fujimoto, Hiroaki
• Primary Examiner(s): To; Tuan C
• Application Number:
  US10/442,003
• Publication Number:
  US 20040006423A1
• Time in Patent Office: 1,806 Days
• Field of Search: 701/210, 701/1, 701/3, 701/7, 701/8, 701/21, 701/25, 701/201, 244/182, 244/191, 244/76.B, 731/78.R, 731/79, 731/701.5, 731/174, 340/994, 440/10, 440/100, 440/38, 114/312, 114/337, 114/144, 744/80.B
• US Class Current: 701/21
• CPC Class Codes: G05D 1/0206 specially adapted to water vehicles

Abstract

A movable object maneuver method wherein a destination point is set; wherein a thrust value is calculated in real time which minimizes or maximizes a performance index associated with one or more state variables and thrust required for a movable object to reach the destination point and which takes into account non-linear conditions inherent to the movable object; and wherein the movable object is moved based on the calculated thrust value.

Claims

1. A method of maneuvering a movable object, comprising:

setting a planned route of the movable object and a destination point on the planned route;

calculating a thrust value in real time which minimizes or maximizes a performance index, over a specified period of time from a present time to a future time, associated with one or more state variables and thrust required for the movable object to reach the destination point;

controlling the movable object to cause the movable object to output the thrust of the calculated thrust value to move the movable object; and

setting constraint of the movable object on the planned route by setting weights for the state variables and the thrust, wherein

the performance index is a function of variables including the weighted state variables and the weighted thrust; and

wherein one or more transit points are set on the planned route, and the control is performed by sequentially setting the one or more set transit points as the destination point.

2. The method according to claim 1, wherein a guide point is set which consists of a virtual point and moves on the planned route, preceding the movable object, and wherein when the guide point has reached a transit point which is the present destination point, the destination point is switched to the next transit point.

3. The method according to claim 1, wherein the weights are set for each zone of the planned route, each zone being defined by the transit points.

4. A method of maneuvering a movable object, comprising:

setting a planned route of the movable object and a destination point on the planned route;

calculating a thrust value in real time which minimizes or maximizes a performance index, over a specified period of time from a present time to a future time, associated with one or more state variables and thrust required for the movable object to reach the destination point;

controlling the movable object to cause the movable object to output the thrust of the calculated thrust value to move the movable object; and

setting constraint of the movable object on the planned route by setting weights for the state variables and the thrust, wherein

the performance index is a function of variables including the weighted state variables and the weighted thrust; and

wherein the weights are set as function of positions.

5. A system for maneuvering a movable object, comprising:

means for setting a planned route of the movable object and a destination point on the planned route;

arithmetic operation means for calculating a thrust value in real time which minimizes or maximizes a performance index, over a specified period of time from a present time to a future time, associated with one or more state variables and thrust required for the movable object to reach the destination point;

a control means for controlling an actuator to cause the actuator to output the thrust of the calculated thrust value to move the movable object; and

means for setting constraint of the movable object on the planned route by setting weights for the state variables and the thrust, wherein

the performance index is a function of variables including the weighted state variables and the weighted thrust; and

further comprising;

means for setting one or more transit points on the planned route, wherein the control means perform the control by sequentially setting one or more set transit points as the destination point.

6. The system according to claim 5, further comprising means for setting a guide point which consists of a virtual point and moves on the planned route, preceding the movable object,

wherein when the guide point has reached a transit point which is the present destination point, the destination point is switched to the next transit point.

7. The system according to claim 5, wherein the means for setting the weights sets

the weights for each zone of the planned route, each zone being defined by the transit points.

8. A system for maneuvering a movable object, comprising:

means for setting a planned route of the movable object and a destination point on the planned route;

arithmetic operation means for calculating a thrust value in real time which minimizes or maximizes a performance index, over a specified period of time from a present time to a future time, associated with one or more state variables and thrust required for the movable object to reach the destination point;

a control means for controlling an actuator to cause the actuator to output the thrust of the calculated thrust value to move the movable object; and

means for setting constraint of the movable object on the planned route by setting weights for the state variables and the thrust, wherein

the performance index is a function of variables including the weighted state variables and the weighted thrust; and

wherein the weights are set as function of positions.

9. A system for maneuvering a movable object, comprising:

means for setting a planned route of the movable object and a destination point on the planned route;

arithmetic operation means for calculating a thrust value in real time which minimizes or maximizes a performance index, over a specified period of time from a present time to a future time, associated with one or more state variables and thrust required for the movable object to reach the destination point;

a control means for controlling an actuator to cause the actuator to output the thrust of the calculated thrust value to move the movable object; and

means for setting constraint of the movable object on the planned route by setting weights for the state variables and the thrust, wherein

the performance index is a function of variables including the weighted state variables and the weighted thrust; and

wherein a state of the movable object is estimated, using a non-linear or linear state observer.