Low inertia rolling control actuation system

Abstract

The system and method of a low inertia, rolling control actuation system (CAS) for a projectile. A CAS having only two canards provides reduced cost and quicker reaction times. In some cases one or more bearings can intermittently decouple the CAS from the projectile and in some cases with the use of a brake. If there are two bearings on either side of the CAS, the front and/or back of the projectile can be decoupled to provide even quicker response times. The front of the projectile may have a warhead and additional sensors or imagers. The rear of the projectile may contain a booster or the like.

What is claimed: 
     
         1 . A low inertia, rolling control actuation system, comprising:
 a projectile having a front portion and a rear portion;   a control actuation system located between the front portion and the rear portion of the projectile, the control actuation system having only two canards;   at least one bearing set located between the control actuation system and the front portion, the rear portion, or both to decouple the control actuation system from the inertia of the front portion, the rear portion, or both the front portion and the rear portion of the projectile;   at least one canard control motor; and   a non-transitory computer-readable storage medium carried by the projectile having a set of instructions encoded thereon that when executed by one or more processors, provide in guidance and navigation of the projectile, the set of instructions being configured to perform:
 coupling of the front portion or rear portion from the control actuation system; 
 decoupling the front or the rear portion from the control actuation system; 
 detecting an angle differential between the front portion or the rear portion and the control actuation system; and 
 moving the control actuation system for a course correction. 
   
     
     
         2 . The low inertia, rolling control actuation system according to  claim 1 , further comprising at least one brake. 
     
     
         3 . The low inertia, rolling control actuation system according to  claim 1 , further comprising an angle measuring device. 
     
     
         4 . The low inertia, rolling control actuation system according to  claim 1 , further comprising an inertial measurement unit. 
     
     
         5 . The low inertia, rolling control actuation system according to  claim 1 , wherein the at least one bearing set is two bearing sets, a first bearing set located between the front portion and the control actuation system and a second bearing set located between the rear portion and the control actuation system. 
     
     
         6 . The low inertia, rolling control actuation system according to  claim 1 , wherein the front portion comprises a warhead. 
     
     
         7 . The low inertia, rolling control actuation system according to  claim 1 , wherein the front portion further comprises one or more sensors. 
     
     
         8 . The low inertia, rolling control actuation system according to  claim 7 , wherein the one or more sensors comprises one or more of the following a LWIR imager, a SWIR imager, a Visible imager, a GPS, an RF antenna, and a SAR antenna. 
     
     
         9 . The low inertia, rolling control actuation system according to  claim 1 , wherein the rear portion comprises a booster. 
     
     
         10 . The low inertia, rolling control actuation system according to  claim 1 , wherein the at least one canard control motor is two canard control motors. 
     
     
         11 . A method of guiding comprising:
 providing a projectile comprising:
 a front portion and a rear portion; 
 a control actuation system located between the front portion and the rear portion of the projectile, the control actuation system having only two canards and at least one canard control motor; and 
 at least one bearing set being located between the control actuation system and the front portion, the rear portion, or both the front and the rear portion; 
   decoupling the control actuation system from the inertia of the front portion, the rear portion, or both the front and rear portion of the projectile via the at least one bearing set;   detecting one or more angle differentials between the control actuation system and the front portion, the rear portion, or both the front portion and the rear portion of the projectile via an angle measuring device;   moving the control actuation system into a radial direction using the control actuation system in a roll maneuver to set up for a course correction for the projectile by counter rotating the two canards of the control actuation system relative to the front portion, the rear portion, or both the front portion and the rear portion via the at least one bearing set and/or the motor and/or the brake; and   applying positive lift or negative lift to the control actuation system via the motor and/or the brake to complete a course correction of the projectile.   
     
     
         12 . The method of guiding a projectile with a low inertia, rolling control actuation system according to  claim 11 , wherein the at least one bearing set is two bearing sets, a first bearing set being located between the front portion and the control actuation system and a second bearing set being located between the rear portion and the control actuation system. 
     
     
         13 . The method of guiding a projectile with a low inertia, rolling control actuation system according to  claim 11 , wherein the front portion comprises a warhead and one or more sensors. 
     
     
         14 . The method of guiding a projectile with a low inertia, rolling control actuation system according to  claim 13 , wherein the one or more sensors comprises one or or of the following a LWIR imager, a SWIR imager, a Visible imager, a GPS, an RF antenna, and a SAR antenna. 
     
     
         15 . The method of guiding a projectile with a low inertia, rolling control actuation system according to  claim 14 , further comprising an inertial measuring unit for maintaining attitude of the one or more sensors during flight. 
     
     
         16 . The method of guiding a projectile with a low inertia, rolling control actuation system according to  claim 11 , wherein the at least one canard control motor is two canard control motors. 
     
     
         17 . A computer program product including one or more non-transitory machine mediums having instructions encoded there on, that when executed by one or more processors, result in a plurality of operations for directing at least one air-borne device toward at least one target, the operations comprising:
 decouple a control actuation system from the inertia of a front portion, a rear portion, or both the front and the rear portion of a projectile via at least one bearing set;   detect one or more angle differentials between the control actuation system and the front portion, the rear portion, or both the front and the rear portion of the projectile via an angle measuring device;   move the control actuation system into a radial direction using the control actuation system in a roll maneuver to set up for a course correction for the projectile by counter rotating the two canards of the control actuation system relative to the front, the rear, or both the front and the rear portion via the at least one bearing set and/or a motor and/or a brake; and   apply positive lift or negative lift to the control actuation system via the motor and/or the brake to complete a course correction of the projectile.