Test method and system for dynamic positioning systems

• US 20060111855A1
• Filed: 04/04/2005
• Published: 05/25/2006
• Est. Priority Date: 11/19/2004
• Status: Active Grant

• Current Assignee: Marine Cybernetics AS (Stiftelsen Det Norske Veritas)
• Original Assignee: Marine Cybernetics AS (Stiftelsen Det Norske Veritas)
• Inventors: Skjetne, Roger, Johansen, Tor Arne, Sorensen, Asgeir Johan
• Granted Patent: US 7,818,103 B2
• Time in Patent Office: Days
• US Class Current: 702/67
• CPC Class Codes: G05D 1/0206 specially adapted to water vehicles

Abstract

A method for testing a marine vessel (0) control system (2), said system (2) receiving real measurement signals (7) from sensors (8) and providing control signals (13) to actuators (16, 17, 18), characterized in

• connecting a signal modifying computer (80) and receiving one or more of said real measurement signals (7),
• said signal modifying computer (80) modifying said real measurement signals (7) into modified measurement signals (70) that depend on the real value of said real measurement signals (7);
• said signal modifying computer (80) sending said modified measurement signals (70) to said control system (2), said one or more modified measurement signal (70) input replacing some or all of said real measurement signal (8) input;
• said control system (2) acting upon said one or more modified measurement signals (70) and remaining unaffected real measurement signals (7);
  for testing whether said control system (2) acts in a desired way on errors represented by said modified measurement signal (70) imagined to occur in one or more sensors (8).

Claims

1. A test system for a marine vessel (0) control system (2) arranged for receiving real measurement signals (7) from sensors (8) and for output of control signals (13) to actuators (16, 17, 18),

characterized by

a signal modifying computer (80) arranged for being connected for receiving one or more of said real measurement signals (7),

said signal modifying computer (80) being arranged for modifying said real measurement signals (7) into modified measurement signals (70) that depend on real values of said real measurement signals;

said signal modifying computer (80) arranged for sending said modified measurement signals (70) to said control system (2), said one or more modified measurement signal (70) input replacing some or all of said real measurement signal (8) input;

said control system (2) arranged for acting upon said one or more modified measurement signals (70) and remaining unaffected real measurement signals (7);

so as for enabling testing of said control system (2) function on errors represented by said modified measurement signal (70) imagined to occur in one or more sensors (8)

2. The test system of claim 1, said marine control system (2) arranged for receiving input cbmmand signals (9) from a command input device (10) on a command signal line (11).

3. The test system of claim 1, said sensors (8) connected to said control system using a sensor signal line (12).

4. The test system of claim 3, said sensor signal line (12) comprising an analog line, a serial line, or a digital ethernet line, a fieldbus or CAN-bus, or a local radio communication system.

5. The test system of claim 1, arranged for outputting control signals (13) to said actuators (16, 17, 18), like propellers (16), thrusters (17), and rudders (18).

6. The test system of claim 1, said signal modifying computer (80) being arranged for modifying said real measurement signals (7) in a relatively short time into modified measurement signals (70), so as for said control system (2) experiencing no significant delay of said modified measurement signals (70) as compared to the corresponding reception time said control system (2) would have received said real measurement signals (7).

7. The test system of claim 1, said control system (2) comprising a power management system 0 including power sensors (8p) for sensing power signals like generator output voltage (7pV), generator output current (7pA), generator power (7pP), fractional total generator power (7pTf), generator status (7pS), and the like.

8. The test system of claim 1, said marine control system (2) arranged for receiving input command signals (9) from a command input device (10) on a command signal line (11).

10. The method according to claim 8, said control system sending control signals (13) to said actuators (16, 17, 18) like propellers (16), thrusters (17), and rudders (18).

9. A method for testing a marine vessel (0) control system (2), said system (2) receiving real measurement signals (7) from sensors (8) and providing control signals (13) to actuators (16, 17, 18),

characterized in

connecting a signal modifying computer (80) and receiving one or more of said real measurement signals (7),

said signal modifying computer (80) modifying said real measurement signals (7) into modified measurement signals (70) that depend on the real value of said real measurement signals (7);

said signal modifying computer (80) sending said modified measurement signals (70) to said control system (2), said one or more modified measurement signal (70) input replacing some or all of said real measurement signal (8) input;

said control system (2) acting upon said one or more modified measurement signals (70) and remaining unaffected real measurement signals (7);

for testing whether said control system (2) acts in a desired way on errors represented by said modified measurement signal (70) imagined to occur in one or more sensors (8).

11. The method according to claim 9, said signal modifying computer (80) modifying said real measurement signals (7) in a relatively short time into modified measurement signals (70), so as for said control system (2) experiencing no significant delay of said modified measurement signals (70) as compared to the corresponding reception time said control system (2) would have received said real measurement signals (7).

12. The method of claim 9, said signal modifying computer (80) modifying one or more of said real measurement signals (7) into one or more modified measurement signals (70) that depend on the real value of said one or more real measurement signals (7), said modified measurement signals (70) being functions of said one or more real values of said measurement signals (7), said functions comprising adding constant or varying values to said real measurement signals (7), multiplying said real measurement signals (7) by constant or varying values, or using linear function depending on said real measurement signal to modify said real measurement signals (7).

13. The method according to claim 9, connecting one or more of said sensors (8) to said control system using one or more of sensor signal lines (12), and connecting said sensor simulator (80) on said sensor signal line (12) for receiving said one or more real sensor signals (8), and modifying said one or more real sensor signals in said sensor simulator (80) into said one or more modified sensor signals (70), and sending said one or more modified sensor signals (70) along said sensor signal lines (12) from said sensor simulator (80) to said control system (2).

14. The method according to claim 9, using one or more serial lines for said sensor signal lines (12), e.g. RS232, RS422.

15. The method according to claim 9, using one or more computer network bus lines like a redundant or non-redundant Ethernet network on UDP protocol, a Fieldbus or CAN-bus, or a radio signal transmission system

16. The method according to claim 9, using one or more ethernet communication lines, a fieldbus or CAN-bus, or a local radio communication system