Device for detecting activation movement for laser gyroscope

• US 6,498,651 B1
• Filed: 10/18/2000
• Issued: 12/24/2002
• Est. Priority Date: 02/19/1999
• Status: Expired due to Term

• Current Assignee: Thomson-Csf Sextant
• Original Assignee: Thomson-Csf Sextant
• Inventors: Loil, Eric
• Primary Examiner(s): Turner, Samuel A.
• Application Number:
  US09/647,936
• Time in Patent Office: 797 Days
• Field of Search: 356/459, 356/472, 356/474, 356/475, 356/476, 310/319, 310/328, 310/331
• US Class Current: 356/476
• CPC Class Codes: G01C 19/70 by mechanical means

Abstract

An actuating motion detection device for a mechanically actuated gyrolaser including at least one fastening ring coaxial with an actuation axis of the gyrolaser. The fastening ring includes a hub held at a center of a rim by radial flexible strips distributed about the hub, and the radial flexible strips are configured to act as springs and to vibrate under an actuating motion. The motion detecting device includes torsion detectors having a pair of piezoelectric plates disposed at a radial position along one radial flexible strip. The piezoelectric plates have respective remanent magnetic fields aligned in opposite directions, and each piezoelectric plate has two electrodes positioned on opposite sides of the piezoelectric plate with one of the two electrodes contacting the radial flexible strip. The electrodes are connected to a common output. In response to deformations of the flexible strips due to rotational motions along the actuation axis, the torsion detectors generate electrical signals of a same polarity that collect at the common output. In response to deformations of the flexible strips coming from motions not along the actuation axis, the torsion detectors generate electrical signals that cancel at the common output.

Claims

1. An actuating motion detection device for a mechanically actuated gyrolaser including at least one fastening ring coaxial with an actuation axis of the gyrolaser, the fastening ring including a hub held at a center of a rim by radial flexible strips distributed about the hub, the radial flexible strips configured to act as springs and to vibrate under an actuating motion, said detection device comprising:

torsion detectors including,

a pair of piezoelectric plates disposed at a radial position along one of the radial flexible strips and having respective remanent magnetic fields for each piezoelectric plate aligned in opposite directions, each piezoelectric plate having two electrodes positioned on opposite sides of the piezoelectric plate with one of said two electrodes contacting said one of the radial flexible strips, and

said two electrodes connected to a common output so that, in response to deformations of the radial flexible strips due to rotational motions along the actuation axis, the torsion detectors generate electrical signals of a same polarity that collect at the common output and, in response to deformations of the flexible strips coming from motions not along the actuation axis, the torsion detectors generate electrical signals of opposite polarities that cancel one another at the common output.

2. Device according to claim 1, wherein for at least one pair of torsion detectors the two electrodes of said piezoelectric plates are connected in an antiparallel connection to the common output.

3. Device according to claim 1, wherein multiple piezoelectric plates are distributed on a same side of different radial flexible strips in accordance with a symmetry of revolution with respect to the actuation axis and the multiple piezoelectric plates have electrodes parallel-connected to the common output.

4. Device according to claim 1, wherein the torsion detectors comprise:

a first pair of said piezoelectric plates having electrodes of said first pair antiparallel-connected to intermediate output terminals; and

a set of multiple piezoelectric plates distributed on a same side of the radial flexible strips in accordance with a symmetry of revolution with respect to the actuation axis and having electrodes of each of said multiple piezoelectric plates parallel connected to the intermediate output terminals.

5. An actuating motion detection device for a mechanically actuated gyrolaser including at least one fastening ring coaxial with an actuation axis of the gyrolaser, the fastening ring including a hub held at a center of a rim by radial flexible strips distributed about the hub, the radial flexible strips configured to act as springs and to vibrate under an actuating motion, said detection device comprising:

torsion detectors including multiple piezoelectric plates distributed on a same side of different radial flexible strips in accordance with a symmetry of revolution with respect to the actuation axis, the multiple piezoelectric plates having electrodes parallel-connected to the common output.