System for the stabilization of an object mounted on a moving platform

• US 6,621,245 B2
• Filed: 02/06/2002
• Issued: 09/16/2003
• Est. Priority Date: 07/16/1997
• Status: Expired due to Term

• Current Assignee: Clipper Windpower Technology, Inc.
• Original Assignee: Thales Nederland BV (Thales SA)
• Inventors: Vaassen, Wilhelmus Marie Hermanus, Stavenuiter, Antonius C. J.
• Primary Examiner(s): Nappi, Robert E.
• Assistant Examiner(s): San Martin, Edgardo
• Application Number:
  US10/066,758
• Publication Number:
  US 20020105298A1
• Time in Patent Office: 587 Days
• Field of Search: 318/648, 318/649, 318/591, 318/609, 318/610, 318/584, 318/585, 318/586, 333/18, 333/21, 333/44, 74/53.4, 74/53.7, 74/57, 244/79, 244/177, 248/184.1, 248/178.1, 248/180.1, 343/765, 343/766, 701/220
• US Class Current: 318/648
• CPC Class Codes: G01C 21/18 Stabilised platforms, e.g. by gyroscope
• CPC Class Codes: H01Q 1/18 Means for stabilising antennas on an unstable platform
• CPC Class Codes: Y10T 74/1225 with rotor drives
• CPC Class Codes: Y10T 74/1282 with rotor drive

Abstract

A calculation system for calculating the control signals which are designed to perform a frequency-dependent weighting of the angular velocity signals and the angular position signals. The angular velocity indicators are preferably used for stabilization in a high frequency band while the angular position indicators are suitable for stabilization in a low frequency band. A further calculation system which is designed to perform the frequency-dependent weighting such that the control signals for frequencies below a certain frequency are substantially determined by the angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

Claims

1. A system for stabilizing an object with reference to a moving platform, comprising:

a stabilization device provided with servo motors and a servo control unit;

a stabilization platform connected to a side of said stabilization device to be stabilized;

an angular velocity measuring device for measuring angular velocities with reference to an inertial coordinate system, wherein said angular velocity measuring device is integrally connected to said stabilization platform;

an angular position measuring device utilizing gyroscopes from a central system on which the object is mounted, said gyroscope configured to encode roll, pitch, and yaw angles;

wherein said servo control unit is configured to control said servo motors based on angular position signals from said angular velocity measuring device and angular position signals from said angular position measuring device; and

wherein said angular position measuring device is connected to said moving platform.

2. A system as claimed in claim 1, wherein said servo control unit is provided with a calculation mechanism configured to combine the angular velocity signals and said angular position signals into additional control signals for said stabilization device.

3. A system as claimed in claim 2, wherein said calculation mechanism, used for calculating said additional control signals, is configured to perform a frequency-dependent weighting of said angular velocity signals and said angular position signals.

4. A system as claimed in claim 3, wherein the calculation mechanism is configured to perform the frequency-dependent weighting such that the control signals for frequencies below a predetermined frequency are substantially determined by said angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

5. A system as claimed in claim 4, wherein said calculation mechanism comprises two complementary filters, connected to said angular position signals and to said angular velocity signals, and a summation device configured to obtain said control signals at least in operational condition.

6. A system as claimed in claim 4, wherein said calculation mechanism include a Kalman filter, the output of which, at least in an operational condition, is configured to produce said control signals.

7. A system for stabilizing an object with reference to a moving platform, comprising:

a stabilization device provided with servo motors and a servo control unit;

a stabilization platform connected to a side of said stabilization device to be stabilized;

an angular velocity measuring device for measuring angular velocities with reference to an inertial coordinate system, wherein said angular velocity measuring device is integrally connected to said stabilization platform;

an angular position measuring device;

wherein said servo control unit is configured to control said servo motors based on angular position signals from said angular velocity measuring device and angular position signals from said angular position measuring device;

wherein said angular position measuring device is connected to said moving platform;

wherein said servo control unit is provided with a calculation mechanism configured to combine the angular velocity signals and said angular position signals into additional control signals for said stabilization device; and

wherein said calculation mechanism, used for calculating said additional control signals, is configured to perform a frequency-dependent weighting of said angular velocity signals and said angular position signals.

8. A system A system for stabilizing an object with reference to a moving platform, comprising:

a stabilization device provided with servo motors and a servo control unit;

a stabilization platform connected to a side of said stabilization device to be stabilized;

an angular velocity measuring device for measuring angular velocities with reference to an inertial coordinate system, wherein said angular velocity measuring device is integrally connected to said stabilization platform;

an angular position measuring device;

wherein said servo control unit is configured to control said servo motors based on angular position signals from said angular velocity measuring device and angular position signals from said angular position measuring device;

wherein said angular position measuring device is connected to said moving platform;

wherein said servo control unit is provided with a calculation mechanism configured to combine the angular velocity signals and said angular position signals into additional control signals for said stabilization device;

wherein said calculation mechanism, used for calculating said additional control signals, is configured to perform a frequency-dependent weighting of said angular velocity signals and said angular position signals; and

wherein the calculation mechanism is configured to perform the frequency-dependent weighting such that the control signals for frequencies below a predetermined frequency are substantially determined by said angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

9. A system as claimed in claim 8, wherein said calculation mechanism comprises two complementary filters, connected to said angular position signals and to said angular velocity signals, and a summation device configured to obtain said control signals at least in operational condition.

10. A system as claimed in claim 8, wherein said calculation mechanism include a Kalman filter, the output of which, at least in an operational condition, is configured to produce said control signals.