PREVENTION OF SERIOUS INJURY BY NON-LETHAL PROJECTILE FIRE FIELD OF THE INVENTION The present invention relates generally to non-lethal projectiles. BACKGROUND OF THE INVENTION Bullets of typical projectile ammunition are built from the main components, shown in Fig. 1A. Projectile (1) – the part that is ejected via the barrel bore towards the target Cartridge Case (2) – cylindrical part that encloses the projectile Burn powder (3) – a measured amount of explosives in the cartridge case that is ejected Primer (4)- a metal part at the bottom of the cartridge case, where sensitive explosive powder resides. Shooting causes the explosion of a small amount of sensitive explosive powder that is in the primer, which lights the explosive material that is in the cartridge case. Burning of the explosive material in the cartridge casing causes the release of gases into the cartridge case space. The gas pressure rises until it pushes the projectile from the edge of the casing into the barrel and from there through the barrel, until the projectile exits the barrel. From the moment the projectile is fired and exits the barrel, it moves in a ballistic trajectory influenced by gravity and by friction between the projectile and the air. The muzzle velocity (the speed with which the projectile exits the barrel) effects the flying range and precision of the projectile. As the muzzle velocity increases, the range and precision increase, and the ballistic flight flattens. The muzzle velocity is influenced by the following parameters: Barrel length Projectile weight Pressure of the gasses in the cartridge casing and in the barrel, caused by the burning of explosive materials in the cartridge case. Non-fatal bullets (rubber, sponge, etc) are used to disperse demonstrations by law enforcement personnel around the world and are shot from a wide variety of rifles and launchers. Parts are shot from rifle extensions to live fire rifles or from ammunition intended for demonstration dispersion. Non-fatal bullets are intended to cause pain, immobilize and/or knock down a person without causing serious injury. Towards this end their shape is large and speed low. Projectiles shot at close range can cause serious injury and even death. There is a correspondence between the shooting range and the injury severity. Fire from non-fatal projectiles at close range can cause serious injuries and disabilities. Severity of non-fatal projectile hits are determined by the following parameters: Projectile velocity v Projectile mass m Area of the injured body 2d , where d is the diameter of the projectile injury (which may be different than its caliber when referring to bullets made of flexible material) Mass of the injured body M Injuries are more severe as the kinetic energy of the projectile2mV, at the moment of impact, rises, as the energy is focused on a smaller area, and as the mass of the injured body is smaller. The non-fatal projectile velocity at the moment of impact is limited by value: md MV 5 .
Or the projectile kinetic energy at the moment of impact is limited by value: d MmV 21 where: M and m in [kg], d in [m] and V in [m/s]. SUMMARY OF THE INVENTION The present invention is intended to prevent serious injuries at targets from any shooting distance as a result of fire from non-lethal bullets. This is accomplished by adjusting the muzzle velocity prior to firing, to a value where the projectile’s kinetic energy, upon impact of the target, will not cause serious injury. Adjustment of the muzzle velocity is done using a controlled release of the gas pressure that ejects the projectile as a function of the distance from the firing position to the target, and of the target’s mass. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawing in which: Fig. 1A illustrates prior art projectile ammunition.
Fig. 1B is a simplified pictorial illustration of a launcher or rifle [A] and projectile ammunition, constructed and operative in accordance with a non-limiting embodiment of the present invention. Fig. 2 ldri bricc ri riFi ci idrissFl rrer ssi p rriF Fig. 3 the barrel Fire pressure from the case. Figure 4 depicts the mechanism for the controlled release of the fire pressure using a linear slider that moves along the barrel. Figure 5 describes the mechanism for the controlled release of the fire pressure using a rotational slider. Figure 6 describes the mechanism for the controlled release of the fire pressure using a solenoid valve. Figure 7 depicts the mechanism for the controlled release of the fire pressure using a solenoid valve. DETAILED DESCRIPTION The device is comprised of a launcher or rifle [A] and projectile ammunition [B] as shown in Figure 1B. The launcher or rifle [A], is composed of a barrel [5], with exit openings [6], a mechanism for the controlled release of gas [10], a laser (or other) range finder [11], a camera for weight estimation [12], and a controller with energy source [13]. The projectile ammunition [B] is comprised of a cartridge case [2], explosive powder [3], projectile [1], a mechanical or electric primer [4], a firing pin [7] when using a mechanical primer or an electric contact for an electric primer. Operation: The range finder [11] measures the distance to the target [14]. The target mass [14] is estimated using the camera [12]. The distance and mass values are broadcast to the controller [13]. The mechanism [10] controls the opening and closing of the exit openings [6]. The controller [13] determines the size of the exit openings [6], based on the range and mass that were measured. The exit opening size is chosen as to decrease the gas pressure that pushes the projectile [1] (hereinafter: "fire pressure"), from the space [15]. Controlling the muzzle pressure ensures that the kinetic energy of the projectile [1] at time of impact with the target [14], will not cause severe damage. Release of the fire pressure by the controller can be done from the barrel [5] after the projectile [1] exits the case [2] as is shown in Figure 2, or from the cartridge case [8] before the projectile [1] leaves the cartridge case [8] as shown in Figure 3 (preferred option). The cartridge case [8] has openings [26] and a circumferential channel [27]. The barrel [5] has openings [9]. During the controlled release of the firing pressure by means of the mechanism [10], the released gases exit through the openings [26] to the circumferential channel [27] and out through the openings [9]. The circumferential channel [27] can be located on the outside of the cartridge case [8] as shown in Figure 3a or on the inside of the barrel [5], as it shown on Fig. 3b. Mechanisms for the controlled release of fire pressure Linear slider Figure 4 depicts the mechanism [10] for the controlled release of the fire pressure using a linear slider [16] that moves along the barrel [5]. Operation: The range finder [11] measures the distance to the target [14]. The target mass is estimated using the camera [12]. The distance and mass values are broadcast to the controller [13]. The controller [13] activates the mechanism [10] that contains an actuator [17] with a nut and screw mechanism [18] (for example only). This in turn operates the linear slider [16] which opens, in a controlled fashion, the gas exit openings [9] according to the controlling the muzzle velocity ensures that the kinetic energy of the projectile [1] at time of impact with the target, will not cause severe damage. Rotational slider Figure 5 describes the mechanism for the controlled release of the fire pressure using a rotational slider [21]. Operation: Rangefinder [11] measures the distance to target [14] The target mass is estimated using the camera [12] The distance and mass values are transmitted to the controller [13] The controller [13] drives the electric motor [23] The electric motor [23] drives gears [22] (for example only). The gear transmission [22] drives the rotary slider [21] so that the openings [20] allow controlled release of the firing pressure through the openings [19] so that the magnitude of the muzzle velocity will ensure that the kinetic energy of the bullet [1] at the moment of hitting target [14] will not cause it serious damage. Solenoid valve Solenoid valve connected directly to the barrel Figure 6 describes the mechanism [10] for the controlled release of the fire pressure using a solenoid valve [24] which is connected directly to the barrel [5]. Operation: The range finder [11] measures the distance to the target [14]. The target mass is estimated using the camera [12]. The distance and mass values are broadcast to the controller [13]. The controller [13] opens and closes the gas exit openings [9] from the space [15] using a solenoid valve [24] at a frequency appropriate for the measured range and mass values, in order to reduce the fire pressure from the space [15] such that muzzle velocity ensures the kinetic energy of the projectile [1] will not cause severe damage at time of impact with the target. Solenoid valve connected via pipe to the barrel Figure 7 depicts the mechanism [10] for the controlled release of the fire pressure using a solenoid valve [24], which is connected to the barrel [5] using piping [25].