Systems and Methods for Dicharging Electrical Energy

TECHNOLOGICAL FIELD

Systems and methods presented herein generally relate to the ignition and/or disabling of explosive devices. More particularly, the invention relates to igniting and/or disabling explosive devices from a defensive perspective (e.g., to explode land mines, improvised explosive devices (IEDs), roadside bombs, etc.).

DESCRIPTION OF THE RELATED ART

Attacks by opposing forces (e.g., military enemies, terrorists and/or militant groups) exist in a variety of forms. Such attacks often include more covert aggression in the form of entrapment devices, or booby-traps, such as landmines and IEDs. These entrapment devices are exceptionally hazardous and often result in lost lives of peacekeeping forces and civilians and damage to vehicles and other equipment. Moreover, the groups of people using such devices are typically unorganized and rely on unconventional methods of attack. When these devices are not used, they are often forgotten and remain as a hazard to non-combatants.

Landmines can be pressure sensitive devices that ignite based on the depression of a triggering mechanism. Such explosive devices may be ignited simply by means of dragging weighted objects across the ground where a landmines lies. For example, during the Vietnam War, helicopters would drag heavy and large metal platforms across the ground to trigger such devices. While this method may still be useful in triggering such devices, it is substantially ineffective at igniting electronically triggered explosive devices, such as IEDs because such devices are not typically designed to ignite upon physical force.

SUMMARY OF THE INVENTION

The systems and methods presented herein generally provide for igniting or disabling explosives. More particularly, these systems and methods relate to igniting or disabling explosive devices, such as landmines and IEDs (e.g., “roadside bombs”). In one embodiment, a strong electric field is generated to cause electric current flow to an explosive device. The electric current is used to ignite explosive material therein and/or disable the detonating electronics while personnel and/or equipment are at a safe “standoff” distance. For example, IEDs are often placed underground or roadside by terrorists and are connected to some sort of triggering mechanism (e.g., a switch in communication with a cellular telephone, or wires connected to a remote switch). The triggering mechanism may be used by terrorists to ignite the IED when, for example, a terrorist's target passes by. Ignition of the IED is generally intended to kill targeted personnel, destroy targeted equipment, and/or terrorize. Ignition or disabling of the IED, with the techniques presented herein, prior to its intended ignition by the terrorist may substantially reduce the effectiveness of such explosive devices.

In one embodiment, electrical energy is transmitted (e.g., capacitively, inductively, and/or through direct discharges) proximate to the explosive device or wires connected thereto from a distally positioned probe to ignite the device. For example, electrical energy may be directly discharged from an electrode to the explosive device. The electrical energy may directly ignite the explosive device through heating and/or indirectly trigger the device by means of electrical propagation through the device's circuitry. The probe, therefore, may provide a safer “standoff” distance. Additionally, the probe may be configured from expendable components such that it may be sacrificed if the explosive is ignited.

In one embodiment, a relatively strong electric field is generated in the vicinity of the explosive device in order to induce electric current that may heat the device. For example, the strong electric field may be such that an induced electric current flows within components of the explosive device (e.g., wires, metal housing and/or the explosive material itself). Additionally, a strong electric field passing in the vicinity of the explosive device may cause electric current to “arc” about metallic edges of the housing and/or current to flow within wires of the device. This electric current may subsequently flow through the trigger, bridgewire, and/or the explosive material of the device to ignite the explosive material. Those skilled in the art are readily familiar with such components. Alternatively, the electric current may damage and/or disable electrical components required to trigger the explosive device (e.g., a discharge across an open switch can close the triggering circuit thereby disabling it). For example, the electrical energy discharge may damage receiver electronics of an explosive device that uses radio triggering. Also, electronic memory of explosive devices may be reset or changed thereby disabling the operations without necessarily causing physical damage to the device. In either case, the explosive device may be rendered inoperable.

In another embodiment, the electric field is generated using a Tesla coil. Other exemplary embodiments, however, may include high-voltage generators, such as those developed by North Star Research Corp. Additionally, such high-voltage generators may be used to supply electric charge to the Tesla coil.

In addition or in the alternative, the strong electric field may create an electrical breakdown in the gas (e.g., air) between the source of the electric field and the explosive device. This breakdown causes electric current to be conducted directly into the device and/or wires connected thereto. This electric current may thereby ignite the explosive material of the device and/or disable the triggering electronics. The electric field may be strong enough to provide an arc of electric current to the device, even if the device is underground. For example, it is well-known that electric current conducted to ground (e.g., earth ground) dissipates within the ground just as lightning dissipates within the ground during a strike. However, a strong enough electric field may create a dielectric breakdown of the air that arcs to ground and penetrates the surface of the ground to some variable depth. This ground penetrating electric current may flow to the explosive device and ignite the explosive material therein. Again, embodiments may include using Tesla coils and/or high-voltage generators such as those described hereinabove to generate the electric field.

In another embodiment, the electromagnetic energy may be created in the microwave range of frequencies. This electromagnetic energy may be used to ignite an explosive device, such as one buried underground. This electromagnetic energy may be received by the device and may heat the explosive's ignition electronics leading to the ignition of the explosive device. For example, the ignition electronics may include a bridgewire, electric fuse, circuitry, power supply, communications, etc. The microwave energy may be propagated through a waveguide instead of broadcast propagation of the energy over a standoff distance. Such directed microwave energy may allow higher radiant intensities to be placed at the explosive device. In another embodiment, electrical energy may be coupled to the explosive device electronics through oscillating magnetic fields. For example, wires attached to the explosive device may inductively receive voltages from the oscillating magnetic flux and cause the explosive device to ignite.

The above-mentioned embodiments may be deployed in a variety of ways. For example, a high-voltage generator may be mounted to a vehicle (e.g., a “wheeled” vehicle, a helicopter, etc.) that travels ahead of a formation (e.g., a single person, a battalion, a group of vehicles, etc.). The vehicle may have one or more arms or “booms” that extend and/or dangle from the vehicle. These booms may include electrodes that are electrically coupled to the high-voltage generator to provide a strong electric and/or magnetic field in the vicinity of an explosive device to thereby ignite the device as described hereinabove. In one embodiment, the electrode is a probe that uses electromagnetic radiation and/or electrical discharge to ignite an explosive device or disable triggering mechanisms thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary vehicle positioned on a roadway.

FIG. 2 is an exemplary top view of the vehicle positioned on a roadway.

FIG. 3A is a schematic diagram illustrating interaction between a vehicle and a target.

FIG. 3B is an alternate schematic diagram illustrating interaction between a vehicle and a target.

FIG. 4A is a perspective view of an exemplary electrode with a connecting member.

FIG. 4B is a perspective view of an exemplary flexible electrode.

FIG. 4C is a perspective view of an alternate configuration of a flexible electrode.

FIG. 5 is a diagram of an exemplary electrical energy delivery circuit and a target.

FIG. 6 is an exploded perspective view of a transformer assembly and an electrode.

FIG. 7 is a perspective view of an exemplary support structure for a transformer assembly.

FIG. 8A is a perspective view of a portion of an exemplary transformer assembly.

FIG. 8B is a cross section of the transformer assembly of FIG. 8A.

FIG. 8C is a side view of the transformer assembly of FIG. 8A.

FIG. 9A is a perspective view of an exemplary gas/electricity flow fitting.

FIG. 9B is a cross section of the gas/electricity flow fitting of FIG. 9A.

FIG. 10 is a perspective view of a portion of an exemplary diode and switch assembly.

FIG. 11 is a side view of a diode array of the diode and switch assembly of FIG. 10.

DETAILED DESCRIPTION OF THE DRAWINGS

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that it is not intended to limit the invention to the particular form disclosed, but rather, the invention is to cover all modifications, equivalents, and alternatives falling within the scope and spirit of the invention as defined by the claims.

FIG. 1 depicts a vehicle 100 used ignite and/or disable explosive devices (e.g., IEDs, roadside bombs, etc.). The vehicle 100 is located along a road 101. In this illustration, the vehicle's forward direction is generally from left to right. Attached to the vehicle 100 is an electrode 102 for distally depositing electrical energy to targets located in proximity to the electrode 102. Electrical energy 104 is shown as being delivered from the electrode 102 to a buried target explosive device 103, depicted in phantom.

The delivery of the electrical energy 104 to the target explosive device 103 may be accomplished either capacitively, inductively, or through direct discharges. In this regard, the vehicle 100 may travel down a road 101 with the distally positioned electrode 102 sweeping a section of the ground 106 in the vicinity of the path of the vehicle 100. As the vehicle 100 travels along the road 101 the electrode 102 may move in proximity with an explosive device 103. How the electrical energy may be generated and transmitted to the electrode 102 is discussed in greater detail below in FIGS. 5 through 11.

The explosive device 103 may be a landmine, IED, or other form of explosive booby trap. The explosive device 103 may be triggered remotely by, for example, a hardwired connection to a remotely located switch or a wireless interface such as those incorporated in cordless or cellular phones. The explosive device 103 may have been buried by enemy combatants or terrorists with the intention of being remotely detonated when a target of opportunity passed in proximity to the explosive device 103. The target of opportunity may be, for example, military personnel, civilian police personnel, members of rival factions, civilians or government personnel. The explosive device 103 may also be in the form of a package, container, box or other configuration resting on top of the ground 106 on or near the road 101.

In one embodiment, a strong electric field is produced by energizing the electrode 102. As the strong electric field is moved into proximity with the explosive device 103, an electrical current flow within the explosive device may be created. The electric current may detonate the explosive material of the explosive device 103 or it may disable the detonating electronics of the explosive device 103. This may be accomplished through several mechanisms. For example, the induced electric current may cause arcing within the explosive device 103 which may directly ignite the explosive material within the explosive device 103. The induced electric current may flow through a trigger, bridge wire, or the explosive material itself resulting in the explosion of the explosive device 103. Alternatively, the induced electric current may damage electrical components required to trigger the explosive device 103, thereby disabling the remote triggering capability of the explosive device 103. Moreover, the induced electric current may generate heat within the explosive device 103 causing the explosive material to ignite.

Alternatively, an electrical discharge may be induced between the electrode 102 and the explosive device 103. Electrical current passing through the discharge and into the target may flow through triggering electronics, a bridge wire, or through the explosive material within the explosive device 103, resulting in the explosion of the explosive device. To explode the explosive material, the electrical current passing through the discharge from the electrode 102 is generally provided by a high voltage generator. An example of such is shown and described below in FIG. 5.

In the illustrated embodiment of FIG. 1, the vehicle 100 is an unmanned remotely controlled vehicle. This allows the personnel operating the vehicle 100 to remain at a relatively safe distance away from the area being swept by the electrode 102 and therefore at a relatively safe distance away from any potential detonation of the explosive device 103. Those skilled in the art of vehicular control should readily recognize that several different methods of remotely controlling the vehicle 100 may be suitable.

In the event of a detonation of the explosive device 103, the distal location of the vehicle 100 relative to the explosive device 103 may result in limited or no damage to the vehicle 100. Damage from a detonation of the explosive device 103 may be limited to the electrode 102. In one embodiment the electrode 102 is easily replaceable so that if the electrode 102 is damaged by an explosion, it may be quickly replaced and the vehicle 100 may continue on its mission. In addition, the electrode 102 may be attached to a transformer 105, wherein the transformer 105 is also easily replaced in the event it is damaged during an explosion. The transformer 105 may be a loosely coupled transformer. To assist in protecting the various components of vehicle 100, the vehicle itself may be armored or hardened to protect it from damage in the event of an explosion.

The strong electric field generated around the electrode 102 may create an electrical breakdown in the air between the electrode 102 and the explosive device 103. This breakdown may cause electric current to be conducted directly into the explosive device 103 or into wires connected to the explosive device 103 and thereby detonate the explosive device 103, ignite the explosive material within the explosive device 103 and/or disable the triggering electronics of the explosive device 103. The electric field surrounding the electrode 102 may be strong enough to provide an arc of electric current to the explosive device 103 even if it is buried. It is well known that electric current conducted to ground dissipates within the ground, for example, as lightning dissipates within the ground during a strike. A strong enough electric field at the electrode 102 may create a dielectric breakdown of the air and allow electrical energy to arc to the ground 106 and penetrate the surface of the ground to some variable depth. This ground penetrating electric current may flow to the explosive device 103.

In the illustrated embodiment of FIG. 1, the vehicle 100 is unmanned and remotely controlled. However, the vehicle 100 itself and the method in which it is controlled may be configured in several different ways. For example, the vehicle 100 may be a manned vehicle with a significant amount of armor to protect its occupants. The remote control of the vehicle 100 in embodiments where the vehicle 100 is unmanned may be in the form of a hardwired remote control or a wireless remote control. In either case, the vehicle 100 may be deployed at the head of a convoy traveling along a road 101 to ignite or disable any explosive devices in the path of the convoy, thereby reducing the probability of damage to the convoy. Multiple vehicles may be deployed to quickly sweep wider areas.

Additionally, although shown with respect to one embodiment, those skilled in the art should readily recognize that the invention should not be so limited. Rather, vehicle 100 may be configured in other ways that fall within the scope and spirit of the invention. For example a vehicle may be configured with the electrode extending from the other side of the vehicle 100. Also, vehicle 100 may be configured with multiple electrodes. The vehicle 100 may be wheeled, as shown, or tracked (e.g., such as a tank). The vehicle 100 may be powered by any method known to those skilled in the art including, but not limited to, diesel, diesel electric, or gasoline power sources. Alternatively, the vehicle 100 may receive power remotely from another vehicle, for example, through an electrical connection between the two vehicles. Also, the vehicle 100 need not be propelled under its own power, the may be towed or pushed by another vehicle (e.g., towed by a helicopter or pushed by a truck).

Additionally, the vehicle 100 is shown traveling along a road 101 and sweeping an area 106 off of the road 101. Alternatively, the vehicle may sweep sections of the road, such as an adjacent lane. The vehicle may also be used to sweep over an area suspected of having an explosive device. For example, the vehicle 100 may be moved to sweep the electrode 102 over a suspicious box or package located in a parking lot or field.

FIG. 2 is a top view of the vehicle 100 of FIG. 1. In this perspective it can be seen at the electrode 102 is angled slightly forward relative to a line perpendicular to the path of travel of the vehicle 100. A grounding chain 201 trails behind the vehicle 100 remaining in contact with the ground. The grounding chain 201 may be required to complete a circuit path when electrical energy is discharged from the electrode 102 to the ground 106. The need for the grounding chain 201 is discussed below in reference to a circuit diagram for the vehicle 100 shown in FIG. 5. The grounding chain 201 may be configured (e.g., as shown herein) where one end is attached to the vehicle 100 and the other end is free to drag on the ground behind the vehicle 100. Alternatively, each end of the grounding chain 201 may be hung from the vehicle 100. By correctly sizing the length of the grounding chain 201 and configuring the attachment points so that they form a line that is generally parallel to the forward direction of travel of the vehicle, the grounding chain 201 may continuously contact the ground without the risk of having the grounding chain 201 come in contact with one of the wheels of vehicle 100 when the vehicle 100 is turning or operating in a reverse gear.

Those skilled in the art will readily recognized that various components depicted in FIGS. 1 and 2 can be varied to achieve differing results. For example, the positioning of the electrode 102 relative to the vehicle 100 can be varied. The electrode 102 can be located further from or closer to the vehicle 100 depending upon the level of armor of the vehicle 100 itself, the area to be swept, or other factors. Additionally, the angle of the electrode 102 relative to the vehicle 100 may be made to vary. The electrode 102 can be extended from the opposite side of the vehicle 100 as shown in FIG. 1. Also, multiple electrodes can be mounted to the vehicle 100. The height of the electrode 102 over the ground 106 may also be varied.

The angulation of electrode 102 shown in FIG. 2 may have advantages over an electrode positioned perpendicular to the path of the vehicle 100. Turning to FIGS. 3A and 3B, schematic diagrams of a vehicle interfacing with a target explosive device are provided. In FIG. 3A, a schematic illustration is provided where the electrode 302 is oriented in a forward swept positioned with respect to the vehicle 300, similar to as depicted in FIG. 2. In FIG. 3A, the explosive device 303 is a remotely activated device controlled by a switch (not shown) connected to the explosive device 303 via a control wire 301. It is expected that in many instances the control wire 301 will be oriented generally perpendicular to the path of the vehicles targeted by the terrorist or enemy combatants who placed the explosive device 303. This is due in part to the tendency of the person controlling the explosive device 303 to be as far away as possible from the path of the targeted vehicles. Also, control wires running parallel to the path of the targeted vehicles may be more conspicuous and lead to unintended detection of the explosive device 303.

As shown in FIG. 3A, a vehicle 300 traveling in direction 304 with a forward swept electrode 302 will first interact with the command wire 301 as the end of the electrode 302 passes over a section of the command wire 301 between the explosive device 303 and a command switch. As discussed above, the interaction between the high-voltage electrode 302 and the command wire 301 may induce a current to flow within the command wire 301. Also as discussed above, a direct discharge of electrical energy into the command wire 301 may occur. This induced current or direct discharge may detonate or disable the explosive device 303. The induced current may also deliver a shock to anyone holding the switch attached to be command wire 301. As the vehicle 300 continues to move in direction 304, the electrode 302 will continue to be in proximity to the command wire 301. If an initial discharge from the electrode 302 does not disable or detonate the explosive device 303, there is still opportunity for the electrode 302 to detonate the explosive device 303 by an additional discharge to the command wire 301 of electrical energy from the electrode 302. The extended period of time that the electrode 302 remains over the command wire 301 may allow an electric current to build up in the command wire 301 due to the electric field emanating from the electrode and moving relative to the command wire 301. This extended period of time may further increase the probability of detonating or disabling the explosive device 303.

Additionally, as the vehicle 300 continues to move forward in direction 304, the electrode 302 will eventually pass directly over the explosive device 303. At this point, the electrical field generated around the electrode 302 and/or a discharge from the electrode 302 may detonate or disable the explosive device 303 directly. The extended time of interaction between the electrode 302 and command wire 301 may also increase the probability of detonation of an explosive device 303 despite the possibility that the explosive device 303 may contain some shielding, for example, in the form of a metal casing, to protect it from electric fields or discharges.

Additionally, if the vehicle 300 with a forward swept electrode 302 is able to detonate the explosive device 303 when the explosive device is forward of the vehicle's 300 position, the vehicle 300 may sustain less damage than would have occurred if the explosive device 303 was detonated when it was directly to the side of the vehicle 300.

Similar advantages may be achieved by angling the electrode 307 in a rearward swept configuration as depicted in FIG. 3B. In FIG. 3B, the vehicle 305 is moving in direction 309. In this configuration, the explosive device 308 is in proximity to the electrode 307 prior to the electrode 307 interacting with the command wire 306. Therefore the initial discharge from the electrode 307 may be directed solely to the explosive device 308. Similar to the configuration of FIG. 3A, the vehicle 305 in the configuration of FIG. 3B provides for an extended period of interaction between the electrode 307 and the command wire 306 relative to what would occur if the electrode 307 were oriented perpendicular to the direction of travel 309 of the vehicle 305.

Although in each of the figures the electrode is shown in a fixed position relative to the vehicle, those skilled in the art should readily recognize that the electrode may be mounted on a rotating or pivoting mount which would allow an operator to adjust the position of the electrode relative to the vehicle to maximize the effectiveness of the electrode. Additionally, decoys may be used by enemy combatants or terrorists in an attempt to thwart the effectiveness of on countermeasures. In this regard, a decoy 310 (FIG. 3A) may be placed proximate to the explosive device 303. While the electrode 302 may discharge to decoy 310, electrode 302 may still discharge to or generate a current within command wire 301. Such may ignite or disable the explosive device 303.

Turning now to FIGS. 4A, 4B and 4C, exemplary configurations of an electrode are illustrated. FIG. 4A illustrates an electrode 400 comprised of a top section 401, and inner electrode loop 402, an outer electrode loop 403, and a pivotable connecting member 404. The top section 401 is configured to interface with the transformer 105. Preferably, the interface is of a design requiring minimal effort to attach and detach the electrode 400 from the transformer 105. This allows the quick replacement of a damaged electrode 400 where the electrode 400 is damaged as a result of an explosion, or during the course of operation. In operation, the bottom section of the inner electrode loop 405, the pivotable connecting member 404, and the bottom section of the outer electrode loop 406 are colinear and electrically connected to be at the same of electric potential. Therefore, when the vehicle 100 is moving, an area in width from the inner bottom corner of the electrode 407 to the outer bottom corner of the electrode 408 will be swept.

Many routes that may contain potential explosive devices that are to be swept by the vehicle 100 may be lined with obstacles such as railings, guard rails, hydrants, etc. In such a case, the pivotable connecting member 404 may be pivoted so that the connecting member 404 is parallel to an outer upright section 409 of the inner electrode loop 402, or 410 of the outer electrode loop 403. In this configuration, a gap will be present between the outer upright section 409 of the inner electrode loop 402 and an inner upright section 410 of the outer electrode loop 403. In this configuration, the electrode 400 may be placed over a guard rail or railing so that the inner electrode loop 402 is sweeping the area on a first side of the guard rail while the outer electrode loop 403 is simultaneously sweeping the area on a second side of the guard rail. To accommodate positioning the electrode 400 over a guard rail or railing, the vehicle 100 may be equipped with a mechanism to raise and lower the electrode 400.

Uneven terrain or obstacles in the areas to be swept by the vehicle 100 for explosive devices may result in an electrode occasionally coming in contact with the aforementioned terrain or obstacles. FIGS. 4B and 4C show configurations of electrodes 411 and 418 respectively that provide flexibility to help prevent damage to the electrodes. FIG. 4B illustrates an electrode 411 similar to electrode 400 in that it comprises a top section 412, and an inner electrode loop 413 and an outer electrode loop 414. Although not illustrated in FIG. 4B, electrode 411 could also be provided with a pivotable connecting member similar to that illustrated in FIG. 4A. In electrode 411, flexibility is provided by four conductive springs 415 situated in upright sections of the inner electrode loop 413 and the outer electrode loop 414. The conductive springs 415 allow the lower sections 416 and 417 of the electrode loops 413 and 414 to pivot with respect to the electrode top section 412. This flexibility may allow for the absorption of impacts with obstructions allowing the electrode to slide or pivot over the obstruction without damage to the electrode. The four conductive springs 415 may be coil springs as shown in FIG. 4B or any other flexible conductive member known to those skilled in the art.

FIG. 4C illustrates an electrode 418 with similar flexibility characteristics to those of electrode 411. However the electrode 418 of FIG. 4C uses nonconductive flexible elements 420 to achieve electrode flexibility. The nonconductive flexible elements 420 may be made of rubber or any other flexible material capable of supporting the lower sections 421 and 422 of the electrode 418. To ensure that the lower sections 421 and 422 are electrically connected to and at the same potential of the rest of the electrode 418, connecting wires 423 may be interconnected to electrically connect the top section of the electrode 419 with the lower sections 421 and 422.

The electrodes illustrated in FIGS. 4A, 4B and 4C may include features to enhance the discharge of electrical energy. For example, the discharge elements may have features such as spikes, ridges or other protrusions along the bottom portions of the electrodes such as elements 404, 405 and 406 shown in FIG. 4A. By extending from the electrodes surface, these features may focus electrical charge to a point where electrostatic discharge is enhanced. For example, a ridge located about the bottom section of electrode 400 may focus electrical fields such that the electrical energy preferentially discharges about the ridge.

FIGS. 4A-4C merely illustrate embodiments which may be used to discharge electrical energy from a vehicle, such as vehicle 100 a FIG. 1. Those skilled in the art should readily recognize that the invention is not intended to be limited to the illustrated embodiments. Rather, electrodes may be configured in other manners to provide electrical energy discharges that similarly destroy, disable, and/or ignite an explosive device.

FIG. 5 illustrates a basic circuit diagram 500 for the delivery of electrical energy to a targeted explosive device 503. In the illustrated example, the components of section 501 of the circuit diagram 500 may be located on the vehicle 100 of FIG. 1, preferably behind shielding or armor to protect the components from detonation of an explosive device 503. The components of section 502, however, may be more exposed to damage from the explosion of an explosive device 503. The components of section 502 of the circuit diagram 500 may be representative of, among other things, electrode 102 and transformer 105 shown in FIG. 1.

Turning now to the components depicted in the circuit diagram 500, a power supply 504 supplies the circuit with high-voltage electricity. The power supply 504 may be in the form of a diesel powered generator capable of generating voltages in excess of 10 kilovolts DC. The power supply 504 may be on board of the vehicle 100, or may be on board a different vehicle wherein the power would be provided to the vehicle 100 remotely through an electrical connection. The illustrated circuit of FIG. 5 depicts an embodiment where a Tesla coil is used to generate the high voltage electrical energy for discharge by electrode 507. Although the illustrated embodiment uses a Tesla coil to generate the high-voltage electrical energy in the electrode 507, it will be apparent to those skilled in the art that other means of generating high-voltage electrical energy may be employed. At least one controller (not shown) may control various functions of the vehicle 100 including, but not limited to, controlling the high-voltage electrical energy from the high-voltage power supply to the electrode 102, vehicle movement, and electrode 102 position.

Prior to the activation of the power supply 504, the thyratron 508 is open. Once the power supply 504 is activated, the Tesla coil primary side capacitor 512 will begin to charge. A 100 watt (W), 100 Ohm (Ω) wire wound resistor 516 may be placed in series with the power supply 504. The Tesla coil primary side capacitor 512 may, for example, be a bank of capacitors with a total capacitance of about 0.2 g. Since, at this stage the thyratron 508 is open, no current will flow through it. Also at this stage, no current will flow through the diode array 506 since the diode array 506 is configured to only allow current flow in one direction, specifically from node 511 to node 510. Once the thyratron 508 is closed, current will flow through the thyratron 508 resulting in a current flowing through a Tesla coil primary coil 513. By opening and closing the thyratron of 508 the electrical energy delivered to the primary coil may be pulsed. Alternatively, the thyratron may be replaced by a semiconductor switch.

In this regard, a thyratron driver 505 may be configured to heat the cathode of the thyratron 508. As such, the primary circuit composed of the Tesla coil primary side capacitor 512 and the primary coil 513 may oscillate with currents with the same polarity as the charging current passing through the thyratron 508 and currents opposite of the charging current passing through the low inductance diode array 506. Through the inductive coupling between the primary coil 513 and the secondary coil 514, energy is transferred to the secondary coil 514. In one embodiment, the Tesla coil primary coil 513 may, for example, have an inductance of 35 microhenries (uH) and the capacitance between the electrode 507 and the ground 515 may be about 29.5 pF. The Tesla coil may be a 100 kHz Tesla coil and the ground 515 may be in the form of electrically conductive chains hanging from the bottom of a vehicle and in contact with the physical ground of earth below the vehicle. Those skilled in the art of designing and building Tesla coils will recognize that the above component values and component positions can be varied while still achieving the desired results of producing strong electrical fields around the electrode 507 and causing discharges from the electrode 507 through an explosive device 503.

If an explosive device 503 is situated between the electrode 507 and a vehicle ground 515 the effect may be to reduce the capacitance of the secondary side of the Tesla coil resulting in a discharge between the electrode 507, through the explosive device 503 and to the ground 515. Alternatively, the electrode may periodically discharge or pulse and recharge at regular intervals, thereby sweeping the area under the electrode with regular discharges. A discharge or pulse of electrical energy generally results in the consumption of electrical energy. Immediately after a discharge from the electrode 507, there may be residual energy remaining within the primary 513 and secondary 514 coils. Prior to the dissipation of this residual energy, the thyratron 508 may be opened, thereby preserving some charge on the capacitors on the primary side of the Tesla coil. By preserving this charge, the amount of energy that must be used to recharge the capacitor 512 on the primary side of the Tesla coil will be reduced in the following charge-discharge cycle.

In an alternate embodiment of the invention, the Tesla coil may be double headed wherein a first Tesla coil secondary electrode experiences a voltage oscillation out of phase with a second Tesla coil secondary electrode in proximity to the first Tesla coil secondary electrode. The strong electric field of each Tesla coil electrode and the voltage oscillation thereof may produce substantial electrical effects which may enhance the ignition or disablement of a target explosive device. The electromagnetic interference (EMI) due to electric fields and discharges, however, generally falls off with the square of the distance from the discharge. Therefore, the amount of EMI emanating from the Tesla coil should have a minimal effect on other electronic and electrical equipment in the vicinity.

Additional circuitry or devices may be included in the vehicle 100 of FIG. 1 to sense the presence of potential explosive devices. These may be stand-alone devices or devices integrated into the Tesla coil circuitry. For example, if an anomalous discharge occurs in a particular spot being swept by the vehicle 100, the vehicle 100 could be positioned so that the electrode 507 is in proximity to that particular spot for an extended period of time.

FIG. 6 is an illustration of an embodiment of a Tesla coil assembly 600 and an electrode 601. The Tesla coil assembly 600 comprises a primary coil 602 (corresponding to the primary coil 513 shown in FIG. 5), the primary capacitor bank 603 (corresponding to the primary side capacitor 512 shown in FIG. 5), a secondary coil (described below and corresponding to the secondary coil 514 shown in FIG. 5) contained within a Tesla coil outer shell 604 and an electrode 601. As shown in FIG. 6, the electrode 601 may attach to the Tesla coil assembly 600 by sliding over an electrode mounting post 605. The electrode 601 made and be fastened to the Tesla coil assembly 600 by any means known to those skilled in the art including pinning, bolting, or through a press fit. The Tesla coil assembly 600 is supported on one end by a Tesla coil assembly support 606. The Tesla coil is assembly support 606 may be a rigid support as shown in FIG. 6, or alternatively may be a pivoting support which would allow the Tesla coil assembly 600 to be pivoted upward.

Although FIG. 6 shows a male electrode mounting post 605 selectably engageable with an electrode 601 with a corresponding female feature, other methods of attaching the electrode 601 to the Tesla coil assembly 600 fall within the scope and spirit of the invention. For example, the electrode 601 may be configured with a male section that is selectably engageable with a corresponding female feature on the Tesla coil assembly 600. Another example would be where the electrode 601 and the Tesla coil assembly 600 both have mating flanges that could be bolted together. Yet, another example, may include the electrode 601 being mounted to the Tesla coil assembly via a hinge mechanism to allow for, e.g., lateral motion of the electrode with respect to the Tesla coil assembly. For example, a mechanical hinge may be configured at the end of the support structure 607 that pivotally engages electrode. In this regard, a spring may also be configured with the structure so that the electrode may swing “open” (e.g., like a gate) when coming in contact with a stationary object (e.g., when vehicle 100 is moving). The spring may then “close” the electrode when the electrode has passed by the object. Alternatively, the hinge may be controlled so as to open and close the electrode as desired. Those skilled in the art, however, should readily recognize that the coupling of the electrode 601 may be coupled to the support structure 607 in other ways that fall within the scope and spirit of the invention.

As discussed above, the electrode 601 may be easily replaced in the event that it is damaged by the detonation of an explosive device. In this regard, it is beneficial to make the electrode as inexpensively as practical. Similarly, the Tesla coil assembly 600 may also be configured to be easily removed and replaced in the event that it should sustain damage. As such, it is also beneficial to make the Tesla coil assembly as inexpensively as practical. To further protect the Tesla coil assembly 600 from damage, a non-conductive shield (not shown) may be placed over the Tesla coil assembly 600. The shield (e.g. Kevlar) may protect the Tesla coil assembly 600 from damage in the event of an explosion and also from damage from small arms fire from enemy combatants or terrorists.

FIG. 7 illustrates the mounting and wiring of a Tesla coil assembly 700 to a vehicle 701 of which only a portion is illustrated. The Tesla coil assembly 700 is supported by a Tesla coil assembly support 702. The Tesla coil assembly support 702 may be made of a conductive material, for example steel, and may also act as a conduit for wires 703 running between the vehicle 701 and the Tesla coil assembly 700. In this embodiment, five wires 703 are shown running from the vehicle 701 through an opening 704 in the Tesla coil assembly support 702 to a junction device 705. The wires 703 correspond to the section of the circuit diagram of FIG. 5 designated by the phantom box 517. The use and routing of the wires 703 allow the power supply 504, thyratron 508, and diode array 506 to be separate and remote from the Tesla coil assembly 700. This allows the power supply 504, thyratron 508, and diode array 506 to be placed in a location where these components are better able to survive an explosion proximate to the electrode.

The five wires 703 connecting the primary coil 706 and primary capacitor bank 707 to the components of section 501 of FIG. 5 may be coaxial cables wired in parallel. The outer conductor of each of the coaxial cables 703 may have, a potential close to ground and correspond to the portion of the circuit diagram of FIG. 5 designated by 518. This configuration results in a lower inductance then would be achieved by non-coaxial wiring. As shown in FIG. 7, the five wires 703 may be routed through an opening 704 in the Tesla coil assembly support 702. The Tesla coil assembly support 702 may be made of a conductive material such as steel, in which case the routing of the five wires 703 through the Tesla coil assembly support 702 further reduces the inductance associated with the five wires 703 (e.g., inductance generally lessens with increasing numbers of wires). This lower inductance allows for an increased length of wires and, thereby, provides for a greater standoff distance. This reduced inductance also allows for a greater length of wire distance between the components of section 501 of FIG. 5 and the Tesla coil assembly 700. The routing of the five wires 703 through the Tesla coil assembly support 702 also protects the five wires 703 from damage from explosions or small arms fire.

By placing the primary capacitor bank 707 on the Tesla coil assembly 700 (as opposed to in proximity with the thyratron or diode array) the outer section of the coaxial cables wired in parallel will be closer to ground and therefore reduce the inductance within the coaxial cables. In other words, returning briefly to FIG. 5, by placing the primary capacitor bank 512 close to the primary coil 513, the ground side wiring 518 of the pair of wires designated by the phantom box 517 is at a lower voltage close to the potential of the ground 519. If in FIG. 5 the primary capacitor bank 512 were in proximity to, for example, node 506, the section of wiring 518 may be at a higher potential and the inductance of the wiring designated by the phantom box 517 would be higher and thereby reduce the effectiveness of an electrical energy discharge.

In an alternate embodiment, the Tesla coil assembly 700 may be pivotable with respect to the vehicle 701 about an axis perpendicular to the surface of the vehicle 701 shown in FIG. 7. For example, the interface between the assembly support 702 and a vehicle 701 shown in FIG. 7 may comprise an assembly similar to a turntable, bearing or other device known to those skilled in the art. An additional pivot axis may allow adjustment or control of the Tesla coil elevation above a horizontal plane.

FIGS. 8A and 8B illustrate details of the assembly of the Tesla coil. FIG. 8A is an external view of the primary side of the Tesla coil. The primary coil 800 may be constructed of copper tubing wound around the Tesla coil outer shell 802. The copper tubing may be about 1.125 inches in diameter and each individual turn, such as the first turn 801, of the coil may be spaced about 0.37 inches apart from the adjacent turns. The spacing between adjacent turns may be maintained by primary coil spacing brackets 804 located on the Tesla coil outer shell 802. The primary coil 800 is connected in series with the primary capacitor bank 805. These components are represented in FIG. 5 by components 513 and 512 respectively.

The Tesla coil outer shell 802 may be made of PVC tubing and may have an outer diameter of about 18 inches. The primary coil 800 may be wrapped seven or eight times around the PVC tubing. However the number of turns in the primary coil 800 along with the diameter of the Tesla coil outer shell 802 may be varied to achieve particular results. Those skilled in the art of Tesla coil design will appreciate that the characteristics of the Tesla coil can be varied by varying the number of turns of the primary and/or secondary coils as well as varying the capacitance of the primary and secondary capacitors and the mechanical configuration of the coils.

FIG. 8B is a sectional view of the Tesla coil illustrated in FIG. 8A sectioned along the line denoted A-A. In FIG. 8B, the first turn 801 of the primary coil 800 can be seen in circling the Tesla coil outer shell 802. The secondary coil 807 may be wrapped around a Tesla coil inner shell 808. Briefly returning to FIG. 8A, the Tesla coil inner shell 808 is held in place with respect to the Tesla coil outer shell 802 by a Tesla coil near end cap 803. The Tesla coil near end cap 803 may be welded or bonded to the Tesla coil outer shell 802 and Tesla coil inner shell 808. A Tesla coil distal end cap (not shown) may be welded or bonded to the Tesla coil outer shell 802 and Tesla coil inner shell 808 in a similar manner. The Tesla coil outer shell 802, Tesla coil inner shell 808, Tesla coil near-end cap 803 and Tesla coil distal end cap may form an enclosed and sealed inter-coil volume 806.

The secondary coil 807 may include about 0.032 inch diameter copper wire wrapped around the Tesla coil inner shell 808 approximately 1000 times over an effective height of about 40 inches. The Tesla coil inner shell 808 may be about 10 inch diameter acrylic tubing. The secondary coil 807 is connected in series with the discharge electrode (for example the electrode 601 of FIG. 6). The opposite end of the secondary coil 807 is connected in series with the ground (for example through the grounding chain 201 in FIG. 2). The inter-coil volume 806 may be filled with a material, such as sulfur hexafluoride, to suppress uncontrolled or undesired discharges involving the secondary coil 807. To electrically connect to the secondary coil 807 and provide a passage for the insertion of the sulfur hexafluoride, at least one electrical/gas feed-through 810 may be included and mounted on the Tesla coil to provide a means of electrical and pneumatic feed-through. An electrical/gas feed-through, such as electrical/gas feed-through 810, is discussed below in detail with reference to FIGS. 9A and 9B.

The inner coil volume 809 may be open to the inter-coil volume 806, for example, by a perforation in the Tesla coil inner shell 808. In this embodiment, the Tesla coil near end cap 803 and the Tesla coil distal end cap would seal the entire volume located within the Tesla coil outer shell 802. The inter-coil volume 806 and the inner coil volume 809 may be filled with sulfur hexafluoride by at least one electrical/gas feed-through 810 configured with Tesla coil near end cap 803, as shown in FIG. 8C.

The Tesla coil may be constructed by first building the secondary coil 807, comprising the step of wrapping copper wire around the Tesla coil inner shell 808. At least one electrical/gas feed-through 810 may be connected to the secondary coil copper wire and mounted so that it protrudes through the Tesla coil inner shell 808. This assembly may then be inserted into the center of the Tesla coil outer shell 802 and held in place by the Tesla coil near-end cap 803 and the Tesla coil distal end cap. The end caps may be affixed to the shells in a variety of methods. For example, the end caps may be ultrasonically welded to the shells, the end caps may be bolted to the shells, or the end caps may be bonded to the shells with an adhesive. The primary coil 800 and primary capacitor bank 805 may be mounted to the Tesla coil outer shell 802 to form the Tesla coil. The inter-coil volume 806 may then be evacuated through an electrical/gas feed-through 810. Sulfur hexafluoride may then be inserted into the inter-coil volume 806. Relative to air, sulfur hexafluoride has insulating properties that may inhibit electrical discharges along the secondary coil. The preceding description of construction of the Tesla coil is intended to be exemplary and is in no way intended to limit the scope of the invention to a particular construction method.

FIGS. 9A and 9B illustrate an exemplary configuration of an electrical/gas feed-through 900. As similarly discussed, an electrical/gas feed-through generally provides both an electrical connection and a gas feed-through between the inter-coil volume 806 and the inner coil volume 809 of the Tesla coil. In this regard, the electrical/gas feed-through 900 may be mounted on the Tesla coil inner shell 808 with the inter-coil end 901 on the outside of the Tesla coil inner shell 808 and the inner coil end 902 on the inside of the Tesla coil inner shell 808. The mounting may be accomplished by engaging a threaded section 905 of the feed-through 900 with a threaded hole in the Tesla coil inner shell 808. The seal between the feed-through 900 and the Tesla coil inner shell 808 may be accomplished by any known sealing means.

The feed-through 900 is constructed of an electrically conductive material such as brass. In this manner, the feed-through 900 itself is able to provide an electrical connection through the Tesla coil inner shell 808. To electrically connect to the feed-through 900, and inter-coil electrical connection point 903 and an inner coil electrical connection point 904 may be provided. These electrical connection points may be threaded holes to enable electrical connectors to be fastened to the feed-through 900. Alternatively, the electrical connection points 903 and 904 may be configured to accept any other kind of electrical connection known to those skilled in the art.

Turning to FIG. 9B, a sectional view of the feed-through of FIG. 9A sectioned by a plane defined by B-B is illustrated. A central passage 909 provides a pneumatic connection between an inter-coil opening 908 and a first inner coil opening 906. The first inner coil opening 906 may be threaded, for example, to accept a standard ¼ NPT fitting. The inter-coil opening 908 need not be configured to accept a fitting and may be left open to the inter-coil volume 806. A second inner coil opening 907 may also be provided and may be configured in a manner similar to the first inner coil opening 906.

The secondary coil may be electrically connected to the electrode 601 of FIG. 6 through an electrically conductive electrode mounting post 605 of FIG. 6 electrically connected to the secondary coil. A support structure 607 of FIG. 6 may support the electrode mounting post 605. Other means may be utilized to electrically connect the secondary coil to the electrode 601, such as, for example, a wire or wires running from the secondary coil to connection points on the electrode 601.

As discussed above, it may be beneficial to locate the electrical power supply, thyratron, and diode array within the vehicle to enhance their survivability in the event of an explosion in proximity to the distal electrode 601. In this regard, the top portion of a thyratron within an enclosure 108 of FIG. 1 and a diode array assembly 107 of FIG. 1 are illustrated. Alternatively, the thyratron within enclosure 108 and the diode array assembly 107 may be completely encased within the vehicle 100 of FIG. 1 to enhance survivability.

Turning to FIG. 10, a thyratron enclosure 1001 (the top portion of which can be seen in FIG. 1 as enclosure 108) provides a sealed environment in which the thyratron is encased. The sealed environment may be filled with an electrically insulating fluid such as oil to provide electrical insulation around the thyratron to avoid unwanted electrical discharges. The fluid may also be circulated between the thyratron enclosure 1001 and a radiator or other external fluid cooling device (not shown) known to those skilled in the art. The fluid may be transported between the thyratron enclosure 1001 and the fluid cooling device via coolant lines 1003.

A diode array 1002 may be mounted to the top of the thyratron enclosure 1001. Due to the high current flow present when the primary coil circuit is oscillating, multiple diodes arranged in a serial-parallel configuration may be required. As illustrated, the multiple diodes may be mounted to multiple mounting boards which in turn may be mounted to the top of the thyratron enclosure 1001.

FIG. 11 shows one exemplary diode array. As shown in FIG. 11, diodes 1101 in the diode array 1100 may be oriented on a mounting board 1102 in a manner to promote airflow around and between the diodes to cool the diodes during operation. In the illustrated example, air in proximity to the diodes may become heated while the diode is conducting current, causing the air to rise in the direction of arrow 1103. This rising air will then be replaced by cooler air, thereby cooling the diodes 1101. In a preferred embodiment, transformer oil is circulated to cool the diodes. As such, the diode array may be configured within a container that holds the transformer oil. This circulation of transformer oil may cool the diodes faster than circulated air. However, those skilled in the art should readily recognize that the manner in which diodes are cooled is generally a matter of design choice. For example, in lower voltage systems (i.e., where heating is generally less), air circulation may be sufficient to cool the diodes.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered as exemplary and not restrictive in character. For example, certain embodiments described hereinabove may be combinable with other described embodiments. Accordingly, it should be understood that only the preferred embodiment and minor variants thereof have been shown and described and that all changes and modifications that come within the scope and spirit of the invention are desired to be protected.

Systems and Methods for Dicharging Electrical Energy

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CPC

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