2-D projectile trajectory corrector

A 2-D projectile trajectory corrector system for improving the trajectory of a spin stabilized artillery projectile after launch, the projectile being tracked after launch by a tracking system, comprising:

• a range adjustment system located within the spin stabilized artillery projectile, wherein said range adjustment system includes a plurality of radially deployable aerodynamic surfaces which increase drag by extending generally perpendicular to a central axis of the spin stabilized projectile, said aerodynamic surfaces are substantially rectangular surfaces with a curved outboard edge and an inboard edge containing a lip which is engagable with the projectile in a maximum deployment position, said aerodynamic surface actuated by a pyrotechnic piston which drives it from a recessed disposition to an exposed aerodynamic disposition, the plurality of radially deployable aerodynamic drag surfaces are selectively deployed for providing an initial correction vector and a final residual correction vector;
• a deflection adjustment system located within the spin stabilized artillery projectile;
• and
• a command module disposed within the spin stabilized artillery projectile and operably coupled to the range adjustment system and the deflection adjustment system.

A 2-D projectile trajectory corrector system for improving the trajectory of a spin stabilized artillery projectile after launch, the projectile being tracked after launch by a tracking system, comprising:

• a range adjustment system located within the spin stabilized artillery projectile;
• a deflection adjustment system located within the spin stabilized artillery projectile, said deflection adjustment system includes a plurality of radially deployable aerodynamic surfaces having an adjustable angle of attack, the angle of attack being adjustable during projectile flight so as to provide an initial correction vector and a residual correction vector, said aerodynamic surfaces extending generally parallel to the central axis of the spin stabilized projectile at a selected angle of attack;
• and
• a command module disposed within the spin stabilized artillery projectile and operably coupled to the range adjustment system and the deflection adjustment system.

A method of adjusting a trajectory of a projectile in-flight by increasing projectile drag to effect a downrange correction and altering the yaw of repose to effect a cross range correction, said method comprising:

• determining a set of coordinates of a target;
• firing the projectile at an initial aim point, wherein said initial aim point is down range and to the right of said target;
• using a tracking system for determining a position of the projectile during flight;
• calculating a trajectory for the projectile and comparing it to a trajectory required to strike the target;
• providing a set of commands to the projectile to adjust said trajectory of the artillery projectile;
• and
• deploying a plurality of aerodynamic surfaces for an initial trajectory correction to range and cross range.

A method of adjusting a trajectory of a projectile in-flight by increasing projectile drag to effect a downrange correction and altering the yaw of repose to effect a cross range correction, said method comprising:

• determining a set of coordinates of a target;
• firing the projectile at an initial aim point, wherein said initial aim point is down range and to the right of said target;
• using a tracking system for determining a position of the projectile during flight;
• calculating a trajectory for the projectile and comparing it to a trajectory required to strike the target;
• providing a set of commands to the projectile to adjust said trajectory of the artillery projectile;
• deploying a plurality of aerodynamic surfaces for an initial trajectory correction to range and cross range;
• monitoring trajectory after said initial correction so as to provide a set of additional trajectory correction instructions as needed;
• and
• deploying a plurality of aerodynamic surfaces for a residual trajectory correction to range and cross range;
• said deployment includes timing a deployment of a plurality of radially extending spin tabs with a swept wing configuration, which are positioned so as to result in selectively decreasing or increasing spin rate to respectively decrease or increase cross range deflection as desired.

A 2-D projectile trajectory corrector system for improving an unguided spin stabilized artillery projectile, said trajectory correction system comprising:

• range adjusting means for reducing the distance the unguided spin stabilized artillery projectile travels, said means including deployment of a plurality of radially extending drag inducing surfaces;
• deflection adjusting means for changing projectile cross range deflection, said means including a timed deployment of a plurality of radially extending aerodynamic surfaces which affect projectile cross range deflection by affecting projectile spin rate;
• tracking means for determining the position of the projectile in-flight so as to correct trajectory errors;
• and
• vernier trajectory correction means for providing at least two stages of trajectory correction so as to correct initial and residual flight error.

An unguided spin stabilized artillery projectile, comprising:

• a projectile body;
• and
• a 2-D projectile trajectory corrector system having:
• a first set of primarily drag inducing surfaces selectively deployable in-flight to effect projectile range, wherein said surfaces are deployed in at least two steps;
• a second set of primarily spin affecting surfaces selectively deployable in flight to affect projectile cross range deflection, wherein said surfaces are deployed in at least two steps;
• and
• an electronic command device operably coupled to the drag inducing and spin affecting surfaces for selectively deploying the drag inducing and spin affecting surfaces.