Redundant inertial measurement system with improved failure-detection capability

Claim 2

A redundant inertial measuring system, comprising: at least two platforms; each platform supporting at least three gyros for stabilizing the platform; the gyros being oriented by disposing the gyro axes substantially normal to the pairs of parallel faces of a regular icosahedron for maximizing the scale triple products of unit vector triads; means for providing signals corresponding to angular misalignment between the platforms; and means connected to the last mentioned means and to selected gyros for controlling said gyros in response to the misalignment signals.

Claim 3

A system as described by claim 1, wherein each of the platforms includes: gimbal means; torquing means supported by the gimbal means; means connected to the gyros supported by the platform for summing output signals therefrom and for providing a summation signal; and the torquing means connected to the summing means and responsive to the summation signal for torquing the gimbal means.

Claim 4

A system as described by claim 1, wherein: each of the platforms includes a base and inner, middle, outer and redundant gimbals; sensors are supported by the base and the gimbals for sensing the angular displacement thereof and for providing corresponding signals; and the means for providing signals corresponding to angular misalignment between the platforms includes means connected to corresponding sensors on selected platforms for summing the signals therefrom.

Claim 5

A system as described by claim 3, wherein: the gyros are supported on the platform inner gimbal.

Claim 6

A system as described by claim 3, including: means connected to the gyros supported by the platform for summing the signals therefrom; torquing means supported by the inner gimbal and connected to the gyro signal summing means for torquing the inner gimbal in response to the signal from said means; torquing means supported by the middle gimbal and connected to the gyro signal summing means for torquing the middle gimbal in response to the signal from said means; torquing means supported by the outer gimbal and connected to the gyro signal summing means for torquing the outer gimbal in response to the signal from said means; and torquing means supported by the redundant gimbal and connected to the outer gimbal sensor for torquing the redundant gimbal in response to the signal from the sensor.

Claim 7

A system as described by claim 5, wherein: the inner gimbal torquing means is coupled to the middle gimbal sensor; the middle gimbal torquing means is coupled to the outer gimbal sensor; the outer gimbal torquing means is coupled to the redundant gimbal sensor; and the redundant gimbal torquing means is coupled to the base sensor.

Claim 8

A system as described by claim 5, including: a resolver connected to the gyro signal summing means and coupled to the inner gimbal torquing means for resolving the signal from said summing means to the inner gimbal outpuT; and the middle and outer gimbal torquing means connected to the gyro signal summing means through the resolver.

Claim 9

A system as described by claim 1, wherein: two platforms are in a coupled pair configuration; and a third platform is slaved to one of the two platforms.

Claim 10

A system as described by claim 8, wherein: each of the three platforms supports three gyros; and the gyro controlling means is connected to one of the gyros on one platform and to two of the gyros on the other platform of the coupled pair, and connected to all three of the gyros on the slaved platform.

Claim 11

A system as described by claim 1, including: means connected to the gyro controlling means and controlled thereby for detecting excessive drift in at least one of the gyros and for eliminating said gyros from the system.

Claim 12

A system as described by claim 1, including: three platforms, each having an inner gimbal for supporting three gyros; and each of the gyro axes being substantially normal to a different pair of the nine parallel pairs of faces of the regular icosahedron and the inner gimbal axes being normal to the tenth pair of parallel faces.

Claim 13

A system as described by claim 1, wherein: each of the platforms includes an inner gimbal; and the gyros are supported on the inner gimbals of the platforms and arranged so that the gyro axes on one platform can be made substantially parallel to the gyro axes on any other platform by rotation about the inner gimbal axis.

Claim 14

A redundant inertial measuring system, comprising: at least two platforms, each of which includes an inner gimbal; each of the inner gimbals supporting at least three gyros for stabilizing the platform, said gyros arranged so that the gyro axes on one platform can be made substantially parallel to the gyro axes on any other platform by rotation about the inner gimbal axis; the gyros being oriented by disposing the gyro axes substantially normal to the pairs of faces of a regular icosahedron for maximizing the scaler triple products of unit vector triads; means for providing signals corresponding to angular misalignment between the platforms; means connected to the last mentioned means and to selected gyros for controlling said gyros in response to the misalignment signals; and means connected to the gyro controlling means and controlled thereby for detecting excessive drift in at least one of the gyros and for eliminating said gyros from the system.

Claim 15

A redundant inertial measuring system, comprising: at least two platforms, each of which includes an inner gimbal; each of the inner gimbals supporting at least three gyros for stabilizing the platform, said gyros arranged so that the gyro axes on one platform can be made substantially parallel to the gyro axes on any other platform by rotation about the inner gimbal axis; the gyros being oriented by disposing the gyro axes substantially normal to the pairs of faces of a regular icosahedron for maximizing the scaler triple products of unit vector triads; means for providing signals corresponding to angular misalignment between the platforms; means connected to the last mentioned means and to selected gyros for controlling said gyros in response to the misalignment signals; and means connected to the gyro controlling means and controlled thereby for detecting excessive drift in at least one of the gyros and for eliminating said gyros from the system.

Claim 16

A system as described by claim 13, including: means connected to the gyros on each of the platforms for summing the signals therefrom and for providing a summation signal; and each of the platforms being connected to a corresponding summing means and controlled by the summation signal therefrom.

Claim 17

A system as described by claim 14, including: means connected to the summing means for resolving the summation signal therefrom to the inner gimbal output; and the platform being connected to the resolving means and controlled by the signal therefrom.

Claim 18

A system as described by claim 13, wherein: each of the gyro axes is substantially normal to a different pair of parallel faces of a regular iscosahedron.