Low cost guiding device for projectile and method of operation
A guiding assembly is adapted to be connected to a projectile and comprising a rear main unit adapted to be connected to the front end of the projectile, and a front main unit rotatably connected at its rear end to the front end of the rear main unit. The front main unit is adapted to rotate about a central longitudinal axis. A relative speed control unit is operable between the rear main unit and the front main unit and capable of providing spin braking force to slow the relative speed of rotation of the front main unit. An at least one guiding fin radially extends from the front main unit. The pitch angle of the fin is controllable by a return spring connected to the fin so that the pitch angle of the fin is growing as the aerodynamic pressure on the fin lowers and it is growing smaller as the aerodynamic pressure on the fin gets bigger.
1. A guiding assembly adapted to be connected to a projectile, comprising:
a rear main unit adapted to be connected at its rear side to a front end of said projectile, said rear main unit having a central longitudinal axis;
a front main unit rotatably connected at its rear end to a front end of said rear main unit and adapted to rotate about said central longitudinal axis;
a relative speed control unit operable between said rear main unit and said front main unit and capable of providing spin braking force to slow the relative speed of rotation of said front main unit, wherein said braking force is controllable;
two guiding fins radially extending from said front main unit, wherein each of said guiding fins is shaped as a flat aerodynamic element having a fin chord extending from the front end of the fin to the rear end of the fin and residing in a plane parallel to said central longitudinal axis, said chord of said fin forms a pitch angle with said central longitudinal axis in said plane parallel to said central longitudinal axis; and
a return spring, operably connected to said guiding fins,
wherein said spring is configured to allow movement correspondingly to aerodynamic pressure on the fins, and wherein said pitch angle is controllable by said spring.
2. The guiding assembly of claim 1 , wherein said pitch angle of said single fin is set at a fixed angle between zero and fifteen degrees.
3. The guiding assembly of claim 1 , wherein said relative speed control unit is an electrical alternator, and wherein the braking force of it is controllable by controlling the amount of electrical power consumed from the alternator.
4. The guiding assembly of claim 1 , wherein the size and pitch angle of said guiding fin are big enough for causing said front main unit to spin in a rotational speed that is faster than the rotational speed of said projectile and is opposite to it in direction, when said projectile is in its trajectory.
5. The guiding assembly of claim 1 , wherein the pitch angle of said fin is controllable.
6. The guiding assembly of claim 5 , wherein the pitch angle of said fins is growing larger as the aerodynamic pressure on the fin lowers and it is growing smaller as the aerodynamic pressure on the fin gets bigger.
7. The guiding assembly of claim 1 , wherein the aerodynamic area of one of the two guiding fins is substantially larger than the other guiding fin.