Counterbalanced triaxial multisensor with resonant accelerometers
First Claim
1. A multisensor comprising, in combination:
- a) a pair of rotors, each of said rotors comprising a plurality of radially-directed rotor arms;
b) means for driving said rotors to counteroscillate at a resonant frequency ω
D ;
c) an accelerometer assembly fixed to each of said rotor arms;
d) each of said accelerometer assemblies including an accelerometer having a substantially-planar proofmass, said proofmass being joined to a substantially-planar accelerometer frame by a hinge so that said proofmass may be angularly displaced with respect to the plane of said frame; and
e) each of said accelerometers being arranged so that a natural frequency of vibration of said proofmass is substantially the same as that of said resonant frequency ω
D.
2 Assignments
0 Petitions
Accused Products
Abstract
A multisensor of the type that employs counteroscillating rotor-mounted accelerometers to measure both linear and Coriolis accelerations operates open loop to sense linear acceleration and closed loop to sense the Coriolis acceleration from angular rate inputs. Accelerometers mounted to arms of the counteroscillating rotors are designed so that the natural frequency of the proofmass with respect to the accelerometer frame closely approximates the resonant frequency ωD of the driven rotor pair. A robust hinge design permits open loop operation for low frequency linear acceleration inputs without saturation. Low voltage closed-loop operation is made possible by the highly compliant nature of the resonant structure in responding to the much higher frequency Coriolis accelerations generated by angular rate inputs.
20 Citations
23 Claims
-
1. A multisensor comprising, in combination:
-
a) a pair of rotors, each of said rotors comprising a plurality of radially-directed rotor arms; b) means for driving said rotors to counteroscillate at a resonant frequency ω
D ;c) an accelerometer assembly fixed to each of said rotor arms; d) each of said accelerometer assemblies including an accelerometer having a substantially-planar proofmass, said proofmass being joined to a substantially-planar accelerometer frame by a hinge so that said proofmass may be angularly displaced with respect to the plane of said frame; and e) each of said accelerometers being arranged so that a natural frequency of vibration of said proofmass is substantially the same as that of said resonant frequency ω
D. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 20, 21, 22, 23)
-
-
13. A multisensor comprising, in combination:
-
a) a pair of rotors, each of said rotors comprising a plurality of radially-directed rotor arms; b) means for driving said rotors to counteroscillate at a resonant frequency ω
D ;c) an accelerometer assembly fixed to each of said rotor arms; d) each of said accelerometer assemblies including an accelerometer having a substantially-planar proofmass, said proofmass being joined to a substantially-planar accelerometer frame by a hinge so that said proofmass may be angularly displaced with respect to the plane of said frame and said hinge being of sufficient stiffness so that the natural frequency of said proof mass is substantially equal to ω
D ;e) means for generating a first signal in response to said angular displacement of said proofmass wherein said first signal provides a measure of linear acceleration; and f) means for generating a second signal in response to said first signal for nulling displacements of said proofmass of frequency substantially equal to ω
D. - View Dependent Claims (14, 15, 16, 17, 18, 19)
-
Specification