STABILIZED CAMERA MOUNT

• US 3,638,502 A
• Filed: 12/01/1969
• Issued: 02/01/1972
• Est. Priority Date: 12/01/1969
• Status: Expired due to Term

• Current Assignee: Edwin C. Dafoe, John N. Leavitt, Raigo Alas
• Original Assignee: Edwin C. Dafoe, John N. Leavitt, Raigo Alas
• Inventors: Leavitt, John N., Alas, Raigo, Dafoe, Edwin C.
• Primary Examiner(s): Antonakas, Manuel A.
• Application Number:
  US04/881,244
• Time in Patent Office: 792 Days
• Field of Search: 74/5.22,5.42,5.44,5.45,5.34 95/12.5
• US Class Current: 74/5.34
• CPC Class Codes: G01C 21/18 Stabilised platforms, e.g. by gyroscope
• CPC Class Codes: G03B 15/00 Special procedures for taking photographs; Apparatus therefor
• CPC Class Codes: Y10T 74/1221 Multiple gyroscopes
• CPC Class Codes: Y10T 74/1236 by plural diverse forces

Abstract

Vehicle-mounted cameras require stabilization to compensate for the erratic movement of the vehicle. This invention provides a stabilized platform for mounting on a vehicle and supporting a camera. The platform is made slightly pendulous so that it is self-erecting to the local vertical and is stabilized first by means of plurality of gyroscopes which provide an artificially amplified mass; and secondly by the movement of suitable real masses, the whole assembly being arranged within a protective fairing and controllable from a remote operators position.

Claims

1. A stabilized platform supported to permit appreciable angular motion about three mutually perpendicular axes, at least three gyroscopes mounted on said platform with their spin axis aligned in three different directions each supported to permit rotational freedom about an axis perpendicular to its spin axis but fixed in other axes whereby rotational movement of the platform is constrained by virtue of the artificial inertia provided by the gyroscopes and such movement causes precession of at least one of said gyroscopes about its rotationally free support axis, means to measure the procession angle of said gyroscope and to produce a signal proportional to said precession angle, a pendent mass suspended from said platform and free to move on two axes at right angles to each other, means responsive to said signal to apply a force between said pendent mass and said platform proportional to said signal and thereby apply a torque to said platform the magnitude and direction of said torque being such as to minimize the rotation of said gyro about its precession axis.

2. A stabilized platform as claimed in claim 1 including a payload means associated with said platform to compensate for changes of center of gravity of said payload including a further mass moved in response to changes in center of gravity caused by operational movement of movable portions of said payload.

3. A stabilized platform as claimed in claim 2 wherein the payload includes an optical device with a movable lens element and said further mass is moved complementary to said lens to compensate for changes of center of gravity which would otherwise be caused by movements of said lens.

4. A stabilized platform as claimed in claim 2 wherein said payload includes a camera with means to cause displacement of film in said camera and said further mass is moved complementary to said film movement to compensate for changes of center of gravity which would otherwise be caused by movement of said film.

5. A stabilized platform as claimed in claim 2 wherein said payload may be steered relative to said platform.

6. A stabilized platform as claimed in claim 3 arranged for operation while supported from a moving vehicle including a rotatable surrounding fairing to protect the platform from wind loading, a window in saId fairing and means to maintain said window aligned with the line of view of said lens elements.

7. A stabilized platform as claimed in claim 1 arranged for operation while supported from a moving vehicle the supporting means including a vibration isolating and damping means including a helical spring and a coaxial helical damper said damper comprising two coaxial metallic helical strips and a layer of nonresilient deformable plastic material interposed between said strips and means to retain said strips and said layer in superposed relationship in the form of a compound strip.