Vibration detection and reduction system and vibration sensors for use in micro-gravity environment

• US 5,571,969 A
• Filed: 05/12/1993
• Issued: 11/05/1996
• Est. Priority Date: 05/14/1992
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Jukogyo Kabushiki Kaisha (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Mitsubishi Jukogyo Kabushiki Kaisha (Mitsubishi Heavy Industries, Ltd.)
• Inventors: Kawasaki, Shuichi
• Primary Examiner(s): Chilcot, Richard
• Assistant Examiner(s): NOORI, MAX H
• Application Number:
  US08/059,753
• Time in Patent Office: 1,273 Days
• Field of Search: 73/505, 73/649, 73/602, 73/652, 73/653, 73/662
• US Class Current: 73/649
• CPC Class Codes: B64G 1/22 Parts of, or equipment specially adapted for fitting in or to, cosmonautic vehicles
• CPC Class Codes: B64G 1/36 using sensors, e.g. sun-sensors, horizon sensors
• CPC Class Codes: B64G 1/38 damping of oscillations, e.g. nutation dampers
• CPC Class Codes: G01H 9/00 Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
• CPC Class Codes: G01P 15/093 by photoelectric pick-up
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G05D 19/02 characterised by the use of electric means
• CPC Class Codes: G10K 11/17823 Reference signals, e.g. ambient acoustic environment
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17873 using a reference signal without an error signal, e.g. pure feedforward
• CPC Class Codes: G10K 2210/129 Vibration, e.g. instead of, or in addition to, acoustic noise
• CPC Class Codes: G10K 2210/3025 Determination of spectrum characteristics, e.g. FFT
• CPC Class Codes: G10K 2210/3029 Fuzzy logic; Genetic algorithms
• CPC Class Codes: G10K 2210/3038 Neural networks
• CPC Class Codes: G10K 2210/3212 Actuator details, e.g. composition or microstructure
• CPC Class Codes: G10K 2210/501 Acceleration, e.g. for accelerometers

Abstract

The invention is to detect vibrations which would destroy a micro-gravity environment, to grasp factors of the vibrations, to detect and grasp a position and a scale of meteoroid/debris collisions, and to establish a counter-measure. Vibration sensors are disposed in a matrix array on a vibrating body placed in a micro-gravity environment. A computer analyzes a spectrum of the vibration, in a neural network section a vibration source is specified on the basis of the analyzed spectra, in a fuzzy control section, actuators are driven so as to reduce harmful vibrations in response to the vibration energy and the energy source specified by the neural network section, and if necessary, a vibration factor is eliminated. The computer takes in the result of driving for the actuators, the results are learnt in the neural network section and in the fuzzy control section to be ready for generation of vibrations at the next time. The vibration sensor comprises a reflector or a transparent refractor disposed as floating in a micro-gravity space, output means fixed to the vibrating body for emitting energy towards the reflector or transparent refractor, and a receiver fixed to the vibrating body for receiving energy sent from the reflector or transparent refractor and measuring the nature of vibrations of the vibrating body on the basis of movement of the reflected or permeated energy.

Claims

1. A vibration factor analyzing system for use in a micro-gravity environment, comprising:

a plurality of vibration sensors disposed on a vibration body held under a micro-gravity environment;

data storage means for storing vibration data of said sensors and a threshold vibration spectra;

analyzing means for analyzing vibration data detected by said vibration sensors to obtain vibration spectra;

a factor extracting section for specifying a vibration source on the basis of a comparison between said vibration spectra obtained by said analyzing means and said threshold vibration spectra stored in said data storage means;

actuators disposed on said vibration body;

an actuator control section responsive to vibration energy detected by said vibration sensor and a vibration source specified by said factor extracting section for controllably driving said actuators so as to reduce harmful vibrations and eliminating the factors of vibrations and for sending data to said data storage means; and

prediction means for predicting a next occurrence of vibrations based on said data and for improving said threshold vibration spectra and sending said prediction and said improved threshold vibration spectra to said data storage means.

2. A vibration sensor for measuring vibrations under a micro-gravity environment, comprising:

a reflector disposed as floating in a micro-gravity space and consisting of a polyhedron having an arbitrary number of surfaces reflecting predetermined energy having various frequencies according to known characteristics;

output means fixed to a vibration body for irradiating said reflector with said predetermined energy; and

receiving means fixed to said vibration body for receiving reflection energy reflected from said reflector and measuring the natures of vibrations of said vibrating body on the basis of variations of said reflection energy

wherein there is provided active vibration suppressing means for holding said reflector and refractor stationary in a micro-gravity space.

4. A vibration sensor as recited in claim 2, wherein said predetermined energy is at least one of laser beams, light, electromagnetic waves and sound waves.

3. A vibration sensor for detecting vibrations under a micro-gravity environment, comprising:

a transparent refractor disposed as floating in a micro-gravity space and having know characteristics;

an irradiator disposed on one side of said transparent refractor and fixed to a structure whose vibrations are to e detected for irradiating with light rays; and

a light receiver disposed on the other side of said transparent refractor as opposed to said irradiator and fixed to said structure for receiving the light rays radiated by the irradiator via the transparent refractor

wherein there is provided active vibration suppressing means for holding said reflector and refractor stationary in a micro-gravity space.

5. A vibration factor analyzing system for use in a micro-gravity environment, comprising:

a plurality of vibration sensors disposed on a vibrating body held under a micro-gravity environment;

analyzing means for collecting vibration data and vibration spectra;

a neural network extracting section for specifying a vibration source on the basis of the vibration spectra analyzed by said analyzing means;

actuators disposed on said vibration body; and

a fuzzy control section responsive to vibration energy detected by said vibration sensor and said vibration source specified by said neural network section for controllably driving some of said actuators so as to reduce harmful vibrations and/or eliminating the factors of vibrations; and

wherein vibration sensor comprises;

a reflector disposed as floating in a micro-gravity space and consisting of a polyhedron having an arbitrary number of surfaces reflecting predetermined energy such as laser beams, light electromagnetic waves, sound waves and the like having various frequencies according to known characteristics;

output means fixed to a vibration body for irradiating said reflector with said predetermined energy; and

receiving means fixed to said vibration body for receiving reflection energy reflected from said reflector and measuring the natures of vibrations of said vibrating body on the basis of variations of said reflection energy.

6. A vibration sensor as recited in claim 5, wherein said predetermined energy is at least one of laser beams, light, electromagnetic waves and sound waves.

7. A vibration factor analyzing system for use in a micro-gravity environment, comprising:

a plurality of vibration sensors disposed on a vibrating body held under a micro-gravity environment;

analyzing means for collecting vibration data and vibration spectra;

a neural network extracting section for specifying a vibration source on the basis of the vibration spectra analyzed by said analyzing means;

actuators disposed on said vibration body; and

a fuzzy control section responsive to vibration energy detected by said vibration sensor and said vibration source specified by said neural network section for controllably driving some of said actuators so as to reduce harmful vibrations and/or eliminating the factors of vibrations; and

wherein vibration sensor comprises;

a transparent refractor disposed as floating in a micro-gravity space and having know characteristics;

an irradiator disposed on one side of said transparent refractor and fixed to a structure whose vibrations are to e detected for irradiating with light rays; and

a light receiver disposed on the other side of said transparent refractor as opposed to said irradiator and fixed to said structure for receiving the light rays radiated by the irradiator via the transparent refractor.

8. A vibration sensor as recited in claim 7, wherein said predetermined energy is at least one of laser beams, light, electromagnetic waves and sound waves.