US20070205560A1

US20070205560A1 - Target and method of making same

Info

Publication number: US20070205560A1
Application number: US11/365,033
Authority: US
Inventors: David Hebble
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-03-02
Filing date: 2006-03-02
Publication date: 2007-09-06

Abstract

A visually and thermally realistic target for firearms shooting practice.

Description

FIELD OF INVENTION

This invention relates to visually and thermally realistic targets for firearms and missiles. Specifically, this invention relates to visually and thermally realistic targets for shooting practice and a method of making such targets.

BACKGROUND OF INVENTION

Various law enforcement and military groups practice the handling of potentially dangerous and problematic situations and have a need for targets that are visually and thermally realistic. Realistic targets are useful for practicing activities necessary to resolve potential conflicts and threats such as attacks conducted from civilian and military vehicles. Similarly, hunters and sportsmen practice shooting using realistic game animal targets such as deer, moose, elk and the like.
Technologies have been developed that include infrared detectors that collect thermal data in an effort to distinguish between decoys and real targets and to identify the true nature of the target. For example, if the threat or target is a human being or a vehicle, thermal sensors can detect and identify the source of heat by matching a thermal pattern emanating from the target with heat patterns emitted by known objects. The use of thermal and visual sensing allows not only differentiation and identification of real and decoy targets but also better classification of the object observed.

SUMMARY OF INVENTION

This invention relates to a decoy or target that has both the visual and thermal characteristics of a real world object to make practice and training effective and realistic. More specifically, this invention relates to a visually and thermally realistic target for shooting practice and a method of creating such target.
In detail, the invention comprises a visually realistic object having heat generating devices that emit thermal radiation having defined patterns.
The method of creating the target comprises the steps of:

- creating a mold defining a cavity representative of an object;
- covering at least a part of the mold with a heater;
- controlling the location of the heater within the mold;
- charging the mold with a measured amount of powdered polymeric material;
- rotating and heating the mold to melt the polymeric powder and coat the surface of the mold to create a target having a visually realistic shape and incorporate the heater therein;
- cooling the mold to fix the molded target; and
- removing the target from the mold.

This invention further comprises the step of providing energy to the heater for causing emission of thermal radiation therefrom creating a thermal image of a real world object.
Still further, this invention comprises coloring the heater to achieve a realistic visual appearance in the molded target.
A primary object of this invention is to produce an object for use as a target that is visually and thermally realistic.
Another object of the invention is to create a visually and thermally realistic target wherein the heater is a thermosetting polymer comprising nickel and polyethelyne powder.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a front view a two dimensional target.
FIG. 2 is a front view of the target of FIG. 1 including a representation of molded in place heaters and electrical circuit for actuating the heaters in the target of FIG. 1.
FIG. 3 is a front view of a three dimensional target.
FIG. 4 is a side view of the three dimensional target of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A polymeric object for use as a firearms shooting target having realistic visual and thermal characteristics is made by a rotational molding process. During the molding process, an electrically actuated heater comprising a mixture of nickel and thermosetting polymer powders and conductive strips or ribbons of similar materials is molded in place in the object to generate an electrically actuated thermal image that is representative of the object being molded. The heat pattern may be representative of any animal, article or machine that radiates heat. For example, the pattern may represent heat from an internal combustion engine, transmission, exhaust, or tracks of a vehicle or the body of an animal such as a human being.
Rotational molding is a manufacturing process that allows for design and production of two and three-dimensional objects.
The rotational molding process starts with a mold that is placed in a molding machine that has loading, heating, and cooling areas. Within reason, the mold may represent the physical appearance of any desired animal or inanimate object such as a vehicle or weapon.
Rotational molding uses a polymeric powder, preferably polyethylene powder. The process is a low pressure process and relies on an oven to heat the mold and melt the powder inside.
A measured quantity of polyethylene resin powder is loaded into the mold, and the mold is moved into an oven where it is heated and rotated about two perpendicular axes, usually vertical and horizontal, concurrently. The molds are located in the oven and slowly rotate about the perpendicular axes. The oven heats the mold and melts the polyethylene powder or resin. The rotational speed, temperature, heating and cooling times are controlled to produce the uniform thickness and other desired features in the finished part. The rotation of the mold about perpendicular axes serves to allow gravity to move the powder and molten polyethylene to achieve full coverage and a uniform thickness of coverage of molten polyethylene over the complete inner surface of the mold.
When the molten polyethylene has fully coated the mold to a constant thickness, the mold moves into a cooling chamber where a combination of air and water are used to cool the mold and turn the molten polyethylene back into a solid.
The mold continues to rotate during the cooling cycle so as to retain the constant wall thickness. After cooling the objects are released and removed from the mold.
As illustrated in FIGS. 1, 2, 3 and 4, targets 10 and 210 produced by the above molding process are used by the military and law enforcement agencies for crisis situation training and practice and are often hit with bullets and other projectiles and punctured. With sufficient hits, the targets will be destroyed and must be replaced. The present invention includes features such as wide electrical input and ground conductor ribbons and conductive graphics. The ribbons and graphics will operate despite damage from projectiles thereby reducing the frequency that replacement of the targets is required.
The graphics used for creating the thermal images are conductive graphics manufactured and sold by Mold In Graphics Systems, PO Box 1650, Clarkdale, Ariz. 86324. The graphics are a mixture of polyethylene powder and a conductive metallic powder, such as nickel. The graphics are manufactured in the form of decals that can be placed in any desired location in a mold.
To start the process of making the target 10 of FIG. 1, a mold is constructed in a manner that will produce the desired shape and contour of the target 10. The target 10 is a silhouette of a military tank and includes portions representing a turret 12, main body 14, and tracks 16 and 18.
As shown in FIG. 2, the decals containing thermal image graphics or heaters 22, 24, 36 and 38 are placed at appropriate locations in the mold. Specifically, the graphics 22 and 24 are placed in the mold so as to be properly positioned to generate heat and emit radiation that simulates the heat pattern of a radiator, engine, etc. in tank body 14. The graphics 36 and 38 are located in the mold so as to generate heat, emit radiation that simulates heat from tracks 16 and 18.
The polyethylene powder necessary to create the primary article, i.e., the target 10, is put in the mold and the heating cycle is started. Because one of the materials of the thermal image graphic decal is polyethylene powder, it melts with the powdered polyethylene and the thermal image graphic becomes a physical part of the molded article.
The mold is closed and placed into the oven. After heating and cooling, the target 10 with the thermal image graphics properly located therein is complete.
The thermal image graphics 22, 24, 36 and 38 are constructed as a powder matrix comprising nickel or other conductive metal powder mixed with polyethylene powder fixed on a decal or other device to secure the powders in place during the locating and molding process. The metal powder in the thermal image graphic is designed to have a high electrical resistance. When a voltage is applied to the graphic, the resistance to current generates heat and radiates a thermal image that corresponds to the configuration of the graphic. In the specific heater of the preferred embodiment, at about 9 volts, the resistance of the electric current raises the temperature of the graphic by about 10 degrees Fahrenheit above ambient. In the preferred embodiment, it takes about 2/10 of a watt to achieve a 10 degree Fahrenheit temperature rise for about every 10 square inches of graphic. The shape of the graphic becomes the heat pattern that is emitted. The shape and location of the graphic in the target 10 depends upon the effect desired for the target. For example, the headlights of a vehicle can have a different thermal signature pattern and be located in a different position in the mold than the engine of that vehicle.
The invention also uses a “wire” graphic or lead 32 and 34 to get the electric power to the above-described conductive graphic. This wire graphics 32 and 34 are generally constructed in a manner that is similar to the thermal image graphic 22, 24, 36 and 38 but the wire graphic 32, 34 has a higher concentration of conductive metallic powder and lower resistance than the thermal image graphic. The additional conductive metal allows the voltage to travel through the wire graphic 32, 34 with a lower electrical resistance and gets the voltage to the thermal image graphic 22, 24, 36 and 38 with less heating the wire graphics 32, 34. Hence, the wire graphics 32, 34 create no detectable thermal image.
As stated above, conductive thermal image graphics 22, 24, 36 and 38 are placed in a predetermined spot on the inner surface of the mold. This creates a thermal image or signature for a portion of the molded object such as a vehicle engine, radiator, headlight, etc. The wire graphics 32, 34 are added in a pattern that provide positive and negative electrical leads to the conductive graphic. Normally the wire conductors terminate at the bottom of the target 10 and the end user of the target would apply a connector, i.e., an alligator clip or otherwise, from an electrical power source 30.
FIG. 1 is a front view of a two dimensional target 10 made with features of the present invention. In FIG. 1, the target 10 represents the silhouette of a military tank. FIG. 1 shows the outline of a tank in full frontal view. In accordance with the present invention, the target 10 has color, height and width giving the target 10 a realistic visual appearance of an actual vehicle.
The visual realism can be increased by adding the third dimension of depth to a target.
FIGS. 3 and 4 show a three dimensional target 210. The target 210 is also a representation of a military tank and includes a turret 212, main body 214 and tracks 216 and 218. In the tank of FIG. 3, the heaters or thermal image graphics for the various patterns would be placed in locations similar to those shown in FIG. 2 to achieve an emitted heat pattern that is realistic for the vehicle represented.
Referring to FIG. 2, the concentration of the nickel particles in the polyethylene powder determines the electrical resistance and hence amount of heat generated by the thermal image graphic heaters 22, 24, 36 and 38, i.e., lower concentrations of particles have higher resistance to current flow and therefore generate higher temperatures than denser concentrations of nickel particles in the conductive ribbon 32. Similarly constructed heaters are designed and shaped to simulate heat radiation from the engine 22, tracks 36 and 38 and radiator 24. Electrical leads or ribbon conductors 32 and ground leads or ribbon conductors 34 are provided to conduct electricity to and from the heat generating graphics 22, 24, 36 and 38. The ribbons 32 and 34 are made with higher concentrations of nickel powder than the heat generating pattern 22, 24, 36 and 38. The higher concentration of nickel in the ribbons 32 and 34 reduces the resistance to current flow and hence the temperature thereof. Thus, the ribbons or leads 32 and 34 do not show up in thermal images of the target 10. The ribbons 32 and 34 are relatively wide help to prolong the life of the target 10 by making the electrical circuit less susceptible to catastrophic failure if one or more of the ribbons 32 or 34 is damaged or severed. The electrical circuit also includes a battery or other source of electrical energy 30 to provide electrical energy to the ribbons 32 and 34 and heat generating patterns 22, 24, 36 and 38.

Claims

1. A method of creating a visually and thermally realistic object comprising the steps of:

creating a mold for producing a visually realistic object;

placing an electrothermal heat generating material comprising a mixture of conductive material powder and a polymeric powder in at least a part of the mold;

controlling the location of the heat generating material within the mold for generating an infrared image representative of a real world object;

providing an electrical conductor in said mold to said heater and from said heater to ground;

charging the mold with a measured amount of powdered polymeric material;

rotating and heating the mold to melt the polymeric powder and coat the surface of the mold to create an object having a visually realistic shape and incorporate the electrothermal material therein;

cooling the mold to fix the molded object; and

removing the target from the mold.

2. The method of claim 1 further comprising the step of:

providing a source of electrical energy to the electrical conductor and heater; and

energizing the electrothermal heat generating material to create a thermal image of said object.

3. The method of claim 1 further comprising the step of:

adding a coloring agent to the mixture of polymeric powder and the electrothermal heat generating material to provide greater visual realism in the molded object.

4. A visually and thermally realistic target comprising:

a polymeric object including an electrically actuated heater incorporated in the object providing a visual and infrared image that is similar to the visual and infrared output of a real object.

5. The visually and thermally realistic target of claim 4 wherein the heater comprises a mixture of nickel and polyethelene powders.