Acceleration measuring system

Claim 1

A system for providing an indication of the acceleration experienced by a vehicle in the plane of the surface over which the vehicle moves, in which the system is mounted on the vehicle body and in which the suspension system of the vehicle permits the vehicle body to pitch and roll with respect to the surface when the vehicle is subjected to acceleration, comprising: acceleration transducer means for providing indications of acceleration in nominal lateral, forward and vertical directions; processor means, including: leveling means, responsive to said indications from said acceleration transducer means, for providing indications of lateral and forward acceleration in a reference plane and of acceleration normal to the reference plane, with reference plane being fixed with respect to the body of the vehicle and horizontal when the vehicle is at rest on a horizontal surface, said leveling means performing the transformation: ##EQU9## where is the acceleration vector with respect to the reference plane, is the acceleration vector in the nominal lateral, forward and vertical directions, α is the angle between the nominal forward direction and the reference plane, and β is the angle between the nominal lateral direction and the reference plane, roll and pitch compensation means, responsive to said indications from the leveling means, for providing indications of lateral and forward acceleration in the plane of said surface, and display means, responsive to said roll and pitch means, for displaying said indications of lateral and forward acceleration in the plane of said surface.

Claim 2

A system for providing an indication of the acceleration experienced by a vehicle in the plane of the surface over which the vehicle moves, in which the system is mounted on the vehicle body and in which the suspension system of the vehicle permits the vehicle body to pitch and roll with respect to the surface when the vehicle is subjected to acceleration, comprising: acceleration transducer means for providing indications of acceleration in nominal lateral, forward and vertical directions; processor means, including: leveling means, responsive to said indications from said acceleration transducer means, for providing indications of lateral and forward acceleration in a reference plane and of acceleration normal to the reference plane, with reference plane being fixed with respect to the body of the vehicle and horizontal when the vehicle is at rest on a horizontal surface, said leveling means performing the transformation: ##EQU9## where is the acceleration vector with respect to the reference plane, is the acceleration vector in the nominal lateral, forward and vertical directions, α is the angle between the nominal forward direction and the reference plane, and β is the angle between the nominal lateral direction and the reference plane, roll and pitch compensation means, responsive to said indications from the leveling means, for providing indications of lateral and forward acceleration in the plane of said surface, and display means, responsive to said roll and pitch means, for displaying said indications of lateral and forward acceleration in the plane of said surface.

Claim 10

A system for providing an indication of the acceleration experienced by a vehicle in the plane of the surface over which the vehicle moves, in which the system is mounted on the vehicle body and in which the suspension system of the vehicle permits the vehicle body to pitch and roll with respect to the surface when the vehicle is subjected to acceleration, comprising: acceleration transducer means for providing indications of acceleration in nominal lateral, forward and vertical directions; processor means, including: leveling means, responsive to said indications from said acceleration transducer means, for providing indications of lateral and forward acceleration in a reference plane and of acceleration normal to the reference plane, with reference plane being fixed with respect to the body of the vehicle and horizontal when the vehicle is at rest on a horizontal surface, roll and pitch compensation means, responsive to said indications from the leveling means, for providing indications of lateral and forward acceleration in the plane of said surface, said roll and pitch compensation means performing the transformation: ##EQU10## where [SURFACE] is the acceleration vector with respect to the surface, [LEVEL] is the acceleration vector with respect to the reference plane, θ is the angle of roll of the vehicle body with respect to said surface, and φ is the angle of pitch with respect to said surface, and display means, responsive to said roll and pitch means, for displaying said indications of lateral and forward acceleration in the plane of said surface.

Claim 11

A system for providing an indication of the acceleration experienced by a vehicle in the plane of the surface over which the vehicle moves, in which the system is mounted on the vehicle body and in which the suspension system of the vehicle permits the vehicle body to pitch and roll with respect to the surface when the vehicle is subjected to acceleration, comprising: acceleration transducer means for providing indications of acceleration in nominal lateral, forward and vertical directions; processor means, including: leveling means, responsive to said indications from said acceleration transducer means, for providing indications of lateral and forward acceleration in a reference plane and of acceleration normal to the reference plane, with reference plane being fixed with respect to the body of the vehicle and horizontal when the vehicle is at rest on a horizontal surface, roll and pitch compensation means, responsive to said indications from the leveling means, for providing indications of lateral and forward acceleration in the plane of said surface, said roll and pitch compensation means performing the transformation: ##EQU10## where [SURFACE] is the acceleration vector with respect to the surface, [LEVEL] is the acceleration vector with respect to the reference plane, θ is the angle of roll of the vehicle body with respect to said surface, and φ is the angle of pitch with respect to said surface, and display means, responsive to said roll and pitch means, for displaying said indications of lateral and forward acceleration in the plane of said surface.

Claim 12

A system for providing an indication of the acceleration experienced by a vehicle in the plane of the surface over which the vehicle moves, in which the system is mounted on the vehicle body and in which the suspension system of the vehicle permits the vehicle body to pitch and roll with respect to the surface when the vehicle is subjected to acceleration, comprising: acceleration transducer means for providing indications of acceleration in nominal lateral, forward and vertical directions; processor means, including: leveling means, responsive to said indications from said acceleration transducer means, for providing indications of lateral and forward acceleration in a reference plane and of acceleration normal to the reference plane, with reference plane being fixed with respect to the body of the vehicle and horizontal when the vehicle is at rest on a horizontal surface, roll and pitch compensation means, responsive to said indications from the leveling means, for providing indications of lateral and forward acceleration in the plane of said surface, said roll and pitch compensation means performing the transformation: ##EQU11## where [SURFACE] is the acceleration vector with respect to the surface, [LEVEL] is the acceleration vector with respect to the reference plane, θ is the angle of roll of the vehicle body with respect to said surface, and φ is the angle of pitch with respect to said surface, wherein said roll and pitch compensation means determines θ and φ by the approximations: θ=xR/(1+zR) and φ=yP/(1+zP), where x is the lateral acceleration component of the vector [LEVEL], z is the vertical acceleration component of the vector [LEVEL], y is the forward acceleration component of the vector [LEVEL], R is roll sensitivity of the vehicle, and P is the pitch sensitivity of the vehicle, and display means, responsive to said roll and pitch means, for displaying said indications of lateral and forward acceleration in the plane of said surface.

Claim 13

A system for providing an indication of the acceleration experienced by a vehicle in the plane of the surface over which the vehicle moves, in which the system is mounted on the vehicle body and in which the suspension system of the vehicle permits the vehicle body to pitch and roll with respect to the surface when the vehicle is subjected to acceleration, comprising: acceleration transducer means for providing indications of acceleration in nominal lateral, forward and vertical directions; processor means, including: leveling means, responsive to said indications from said acceleration transducer means, for providing indications of lateral and forward acceleration in a reference plane and of acceleration normal to the reference plane, with reference plane being fixed with respect to the body of the vehicle and horizontal when the vehicle is at rest on a horizontal surface, roll and pitch compensation means, responsive to said indications from the leveling means, for providing indications of lateral and forward acceleration in the plane of said surface, said roll and pitch compensation means performing the transformation: ##EQU11## where [SURFACE] is the acceleration vector with respect to the surface, [LEVEL] is the acceleration vector with respect to the reference plane, θ is the angle of roll of the vehicle body with respect to said surface, and φ is the angle of pitch with respect to said surface, wherein said roll and pitch compensation means determines θ and φ by the approximations: θ=xR/(1+zR) and φ=yP/(1+zP), where x is the lateral acceleration component of the vector [LEVEL], z is the vertical acceleration component of the vector [LEVEL], y is the forward acceleration component of the vector [LEVEL], R is roll sensitivity of the vehicle, and P is the pitch sensitivity of the vehicle, and display means, responsive to said roll and pitch means, for displaying said indications of lateral and forward acceleration in the plane of said surface.