Description:FIELD OF THE INVENTION:

The invention relates to a technical field of airborne or aerospace application. In particular, the invention relates to a munitions arming unit for airborne application. More particularly, the invention relates to a novel design of munitions arming unit with robust safety mechanism for munitions to prevent any inadvertent firing during handling and operation.

BACKGROUND OF THE INVENTION:

A munition arming unit provides a mechanism for sensing whether conditions exist for the arming of a munition. This arming process can include initiation of release of the munition from a platform (such as an aircraft), and further may include the generation of trigger signals to initiate detonation of the munition. Thus, an arming unit generally includes mechanisms configured to avoid inadvertent arming and release of a munition. In one paradigm, regulations may be imposed that two independent measurable parameters must be sensed with respect to predetermined thresholds, before a munition arming unit can enter the armed state. According to established standard procedures, the first of these parameters is whether or not a signal has been received indicating intent to release the munition. The second of these parameters may be related to a measure indicating that one or more conditions of the environment, in which the munition platform resides, match parameters which would normally be associated with release of the munition. Existing arrangements involve some form of environmental sensing. That is, mechanisms are provided for detection of certain measurable criteria of the environment and to use these as a safeguard to ensure that actions on a munition are not misinterpreted as a trigger for arming and/or release.

However, such existing mechanisms may suffer from drawbacks. For instance, they may not be entirely independent of primary arming and release conditions, they may directly affect the performance of the associated munition, they may require specific initiation arrangements on-board the munition platform prior to release, and they may require specific arrangements on-board the munition platform to deal with possible icing, which could affect arming and release.

US Patent No. US11280600B2 discloses a safety and arming device for a munition is operable to arm and initiate a munition dependent on determining separation from a munition platform, determining detection of free fall of the device for a first time period following separation, initiating a roll manoeuvre of the munition and determining detection of the execution of the roll manoeuvre within a second time period, and generating a munition firing signal, dependent on detection of all of separation, free fall, and the roll manoeuvre. A system comprises an aircraft providing a deployment platform for a missile munition. The aircraft and missile are engaged with each other electrically by means of a plug and socket arrangement. The missile comprises a guidance system and a safety and arming device. These are engaged with each other by a plug and socket arrangement. The connection between the guidance system and the safety and arming device provides the ground line, carried through from the aircraft, so that the separation sensing can be carried out at the safety and arming device. However, the device of prior art does not use the umbilical connector comprising microcontroller for coupling of aircraft and missile; guidance system and the safety and arming device wherein the safety and arming device cannot be accommodated in miniaturized space available within the bomb shell. Also, the safety cap provided on munition surface is not disclosed. Further, the device of prior art is bulky, generally mechanical in nature, considers only few safety criteria and it is non-configurable.

PCT Publication No. WO2018/127922A1 discloses the examples of safety devices for use with a munition, the munition including a munition explosive and a safe and arm (S&A) device for activation of the munition explosive. In some examples, the safety device includes a switch member and an actuation mechanism. The switch member is configured for being disposed between the munition explosive and the S&A device, the switch member being movable between at least two switch positions. In a first switch position (an arming prevention position (APP)), arming communication between the munition explosive and the S&A device is prevented. In a second switch position (an arming enabling position (AEP)), arming communication between the munition explosive and the S&A device is allowed. The actuation mechanism is configured for selectively moving the switch member at least from the APP to the AEP to thereby enable the S&A device, when armed, to detonate the munition explosive via the switch member. However, the device of prior art does not use the umbilical connector for coupling of missile and drone wherein the safety and arming device cannot be accommodated in miniaturized space available within the bomb shell. Also, the safety cap provided on munition surface is not disclosed. Further, the device of prior art is bulky, generally mechanical in nature, considers only few safety criteria and it is non-configurable.

Limitations of known art:
- Bulky
- Generally Mechanical in nature, consider only few safety criteria
- Non-configurable

Therefore, there is a need to design a novel munitions arming unit with robust safety mechanism for munitions to prevent any inadvertent firing during handling and operation. Thus, a safety device for the munition arming unit which is of relatively simple construction and can be accommodated in the miniaturized space available within the bomb shell is required to be provided.

The present invention relates to a munitions arming unit for airborne application. The present invention discloses the arming of airborne bombs/munitions, particularly 1 kg and 3.5 kg bombs intended to be dropped off from airborne platforms including drones moving in swarms. These munitions are specifically designed using sleeve fragmented warheads targeted for anti-personnel and anti-material. It is imperative that these munitions are safe to handle while transporting and at the time when the carrier platform is getting airborne. It is to be ensured that the munitions shall be made armed only when it is intended.

The munitions are built with a Safety and Arming mechanism (SAM) having a primary function to provide arming and detonation of the warhead whenever intended. To avoid any potential for any mishap, to both, airborne platform (drone) and personnel, a novel safety device is designed to ensure that the weapon is in “armed” condition only when desired and in “safe” condition at all other times. This safety device is an integral part of the munitions to prevent any inadvertent firing of the munitions. Thus, the safety and arming device is provided which is relatively simple in construction and can be accommodated in the miniaturized space available within the bomb shell. The munitions and the drone are interfaced/communicatively coupled with a lanyard interface (umbilical) connector. It consists of a microcontroller capable of communicating serially with drone and SAM.

OBJECT(S) OF THE INVENTION:

A primary object of the present invention is to design a munitions arming unit for airborne application.

Another object of the present invention is to design a munitions arming unit with a safety device which is relatively simple in construction and can be accommodated in the miniaturized space available within the bomb shell.

Another object of the present invention is to design a munitions arming unit with robust safety mechanism for munitions to prevent any inadvertent firing during handling and operation.

Another object of the present invention is to provide a safety cap on the munitions surface for safe handling during mounting of the munitions on the platform or drone and while transporting them.

Another object of the present invention is to design a munitions arming unit wherein the warhead (explosive’s) igniter terminals are brought out the umbilical connector to ensure that the munitions are safe as long as they are connected to the drone.

Another object of the present invention is to design a munitions arming unit comprising a timer-based feature and the micro electro-mechanical system (MEMS) based 3 axes accelerometer is also integrated to provide flexibility in detonating on various terrains.

Another object of the present invention is to design a munitions arming unit wherein a reliable arming delay of 2 seconds is provided to ensure that the bomb has travelled a safe distance after releasing the bomb.

Yet another object of the present invention is to define the working method of munitions arming unit to configure the detonation scheme via different possible ways.

SUMMARY OF THE INVENTION:

Accordingly, the present invention provides a munitions arming unit for airborne application. In particular, the present invention relates to a novel design of munitions arming unit with robust safety mechanism for munitions to prevent any inadvertent firing during handling and operation. More particularly, the present invention relates to a safety device to the munitions arming unit which is relatively simple in construction and can be accommodated in the miniaturized space available within the bomb shell.

The present invention discloses the arming of airborne bombs/munitions, particularly 1 kg and 3.5 kg bombs intended to be dropped off from airborne platforms including drones moving in swarms. These munitions are specifically designed using sleeve fragmented warheads targeted for anti-personnel and anti-material. It is imperative that these munitions are safe to handle while transporting and at the time when the carrier platform is getting airborne. It is to be ensured that the munitions shall be made armed only when it is intended.

The munitions are in-built with a Safety and Arming mechanism (SAM) having a primary function to provide arming and detonation of the warhead whenever intended. To avoid any potential for any mishap, to both, airborne platform (drone) and personnel, a novel safety device is designed to ensure that the weapon is in “armed” condition only when desired and in “safe” condition at all other times. This safety device is an integral part of the munitions to prevent any inadvertent firing of the munitions.

In one aspect of the present invention, the invention provides a munitions arming unit (10) for airborne application, the munition arming unit (10) comprises:
a Safety and Arming mechanism (SAM) to provide arming and detonation of the warhead whenever intended;
an umbilical connector (8) for coupling a munition (M) and a drone;
a safety cap (14) provided on the surface of the munition (M);
a timer-based feature;
a micro electro-mechanical system (MEMS) based 3 axes accelerometer;
wherein the umbilical connector (8) comprises a microcontroller capable of communicating serially with the drone and the safety and arming mechanism (SAM);
wherein the safety cap (14) shorts the igniter terminal of safety and arming mechanism (SAM) of munition arming unit (10) for safe handling during mounting of the munitions (M) on the drone and while transporting them.

The safety cap (14) is divided into two parts comprising a shorting plug (14a) and a receptacle (14b).

The igniter terminals of warhead of explosive contained in the charge (9) of warhead assembly (2) are brought out to the umbilical connector (8).

In another aspect of the present invention, the invention provides a munition (M) comprising the munition arming unit (10) with safety and arming mechanism (SAM), wherein the munition (M) comprises:
- a nose assembly (1);
- a warhead assembly (2); and
- a rear assembly (3);
wherein the structures for nose assembly (1) and rear assembly (3) are made up of aluminium alloy; and
wherein the structure of warhead assembly (2) is made up of EN-24 steel material.

The nose assembly (1) comprises a battery (6), a safety connector (7), a G-switch (4) of 50 g and a Printed Circuit Board (PCB) (5).

The warhead assembly (2) comprises a safety and arming mechanism (SAM) of munition arming unit (10) and a charge (9) filled with an explosive.

In another aspect of the present invention, the invention provides a method for working of a munition arming unit (10) with safety and arming mechanism (SAM), wherein the method comprises:
- turning ON a munition (M) from a drone through an umbilical connector (8);
- configuring the detonation scheme from the drone through communication commands;
- performing a self-test and/or a built-in-test on power up;
- sending a health status;
- selecting a detonation option;
- generating an ARM pulse when the bomb is released from the drone;
- generating a FIRE pulse depending on the detonation option selected and/or through self-destruction timer after a stipulated time is elapsed;
wherein the ARM pulse is generated after 2 seconds from umbilical snap of the munition (M) and the drone.

The munition (M) gets powered OFF after 3 seconds on detecting the umbilical snap between munition (M) and the drone after power up.

An arming delay of 2 seconds is provided to measure the travelled distance of the bomb after releasing.

After arming, the bomb is detonated by timer or impact or micro electro-mechanical system (MEMS) based 3 axes accelerometer or self-destruction timer of 22 seconds.

The above description merely is an outline of the technical solution of the present disclosure. The summary is descriptive and exemplary only and is not intended to be in any way restricting. In order to know the technical means of the present disclosure more clearly so that implementation may be carried out according to contents of the specification, and in order to make the above and other objectives, characteristics and advantages of the present disclosure clear and easy to understand, specific embodiments of the present invention will be described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS:

The drawings described herein are intended to provide a further understanding of the invention and are intended to be a part of the invention. However, the drawings as shown are representative for illustration and are non-limiting the scope of the invention. In the drawings:

Figure 1 shows the structural diagram of munition (M) comprising a nose assembly (1), a warhead assembly (2) and a rear assembly (3).

Figure 2 shows the larger view of nose assembly (1) comprising G-switch (4) and Printed Circuit Board (PCB) (5).

Figure 3 shows the prototype image of warhead assembly (2) comprising a munitions arming unit (10) with safety and arming mechanism (SAM) and the connections (12) of safety and arming mechanism (SAM) with Printed Circuit Board (PCB) (5).

Figure 4a shows the coupling of munition (M) and drone with umbilical connector (8).

Figure 4b shows the prototype image of umbilical connector (8).

Figure 4c shows the drone side umbilical cable (13).

Figure 5a shows the prototype image of a safety cap (14).

Figure 5b shows the prototype image of a shorting plug (14a) having two adapters (14c).

Figure 5c shows the prototype image of a receptacle (14b) having two elongated slots (14d).

Figure 5d shows the prototype image of munition (M) wherein a safety cap (14) is connected in a circular portion (A).

Figure 5e shows the prototype image of a munition (M) from which the safety cap (14) is removed in a circular portion (B).

Figure 6 shows the flowchart of the working method steps of munition arming unit (10) with safety and arming mechanism (SAM).

DETAILED DESCRIPTION OF THE INVENTION:

The present invention relates to a munitions arming unit for airborne application.

A munition arming unit provides a mechanism for sensing whether conditions exist for the arming of a munition. This arming process can include initiation of release of the munition from a platform (such as an aircraft), and further may include the generation of trigger signals to initiate detonation of the munition. Thus, an arming unit generally includes mechanisms configured to avoid inadvertent arming and release of a munition. In one paradigm, regulations may be imposed that two independent measurable parameters must be sensed with respect to predetermined thresholds, before a munition arming unit can enter the armed state. According to established standard procedures, the first of these parameters is whether or not a signal has been received indicating intent to release the munition. The second of these parameters may be related to a measure indicating that one or more conditions of the environment, in which the munition platform resides, match parameters which would normally be associated with release of the munition. Existing arrangements involve some form of environmental sensing. That is, mechanisms are provided for detection of certain measurable criteria of the environment and to use these as a safeguard to ensure that actions on a munition are not misinterpreted as a trigger for arming and/or release.

However, such existing mechanisms may suffer from drawbacks. For instance, they may not be entirely independent of primary arming and release conditions, they may directly affect the performance of the associated munition, they may require specific initiation arrangements on-board the munition platform prior to release, and they may require specific arrangements on-board the munition platform to deal with possible icing, which could affect arming and release.

Accordingly, the present invention relates to a munitions arming unit for airborne application. The present invention discloses the arming of airborne bombs/munitions, particularly 1 kg and 3.5 kg bombs intended to be dropped off from airborne platforms including drones moving in swarms. These munitions are specifically designed using sleeve fragmented warheads targeted for anti-personnel and anti-material. It is imperative that these munitions are safe to handle while transporting and at the time when the carrier platform is getting airborne. It is to be ensured that the munitions shall be made armed only when it is intended.

The munitions are built with a Safety and Arming mechanism (SAM) having a primary function to provide arming and detonation of the warhead whenever intended. To avoid any potential for any mishap, to both, airborne platform (drone) and personnel, a novel safety device is designed to ensure that the weapon is in “armed” condition only when desired and in “safe” condition at all other times. This safety device is an integral part of the munitions to prevent any inadvertent firing of the munitions. Thus, the safety and arming device is provided which is relatively simple in construction and can be accommodated in the miniaturized space available within the bomb shell. The munitions and the drone are interfaced/communicatively coupled with a lanyard interface (umbilical) connector. It consists of a microcontroller capable of communicating serially with drone and safety and arming mechanism (SAM).

In one aspect of the present invention, the invention provides the munition arming unit (10) with safety and arming mechanism (SAM) for airborne application mounted in the warhead assembly (2) of munition (M).

Figure 1 shows the structural diagram of munition (M) comprising a nose assembly (1), a warhead assembly (2) and a rear assembly (3).

The munition (M) is comprised of three structural assemblies that is, a nose assembly (1), a warhead assembly (2) and a rear assembly (3). The material used to make the structures for nose assembly (1) and rear assembly (3) is aluminium alloy. The structure of warhead assembly (2) is made up of EN-24 steel material. The construction of munitions (M) starts from nose assembly (1), warhead assembly (2) and then rear assembly (3). All electronics and safety features are incorporated in munition (M) and in particular, an impact switch and/or G-switch of 50 g is mounting in the nose assembly (1).

The nose assembly (1) of munition (M) as shown in figure 1 comprises a battery (6) and a safety connector (7). The warhead assembly (2) comprises a safety and arming mechanism (SAM) of munition arming unit (10) and a charge (9) filled with an explosive.

As shown in figure 2, the nose assembly (1) also comprises a G-switch (4) of 50 g and Printed Circuit Board (PCB) (5).

Figure 3 shows a safety and arming mechanism (SAM) of munition arming unit (10). The circular portion of figure 3 shows the connections (12) of safety and arming mechanism (SAM) from Printed Circuit Board (PCB) (5).

Thus, the above-mentioned description can be summarized as, a munition (M) comprising the munition arming unit (10) with safety and arming mechanism (SAM), wherein the munition (M) comprises:
- a nose assembly (1);
- a warhead assembly (2); and
- a rear assembly (3);
wherein the structures for nose assembly (1) and rear assembly (3) are made up of aluminium alloy; and
wherein the structure of warhead assembly (2) is made up of EN-24 steel material.

Figure 4a shows the lanyard interface connector called an umbilical connector (8). The prototype image of the umbilical connector (8) is shown in figure 4b. Figure 4c shows the drone side umbilical cable (13). The munition (M) and the drone (not shown) are interfaced or communicatively coupled with a lanyard interface i.e., umbilical connector (8). The umbilical connector (8) consists of a microcontroller (not shown) capable of communicating serially with drone and safety and arming mechanism (SAM).

Figure 5a shows the structure of a safety cap (14). The safety cap (14) is provided on the munitions surface. It shorts the igniter terminal of safety and arming mechanism (SAM) of munition arming unit (10) for safe handling during mounting of the munitions on the platform (drone) and while transporting them.

In particular, the safety cap (14) has two parts, one is a shorting plug (14a) as shown in figure 5b and the other is a receptacle (14b) as shown in figure 5c. The shorting plug (14a) has two adapters (14c) to be inserted in the elongated slots (14d) of receptacle (14b) while connecting the safety cap (14) to the munition (M). Figures 5d and 5e show the safety cap (14) connected to the munition (M) in circular portion A and the safety cap (14) removed from the munition (M) in circular portion B, respectively.

In the present invention, the igniter terminals of warhead of explosive contained in the charge (9) of warhead assembly (2) are also brought out to the umbilical connector (8) to ensure that the munition (M) is safe as long as it is connected to the drone.

Thus, the above-mentioned description can be summarized as, a munitions arming unit (10) for airborne application comprises:
a Safety and Arming mechanism (SAM) to provide arming and detonation of the warhead whenever intended;
an umbilical connector (8) for coupling a munition (M) and a drone;
a safety cap (14) provided on the surface of the munition (M);
a timer-based feature;
a micro electro-mechanical system (MEMS) based 3 axes accelerometer;
wherein the umbilical connector (8) comprises a microcontroller capable of communicating serially with the drone and the safety and arming mechanism (SAM);
wherein the safety cap (14) shorts the igniter terminal of safety and arming mechanism (SAM) of munition arming unit (10) for safe handling during mounting of the munitions (M) on the drone and while transporting them.

In another aspect of the present invention, the invention provides the working method of munition arming unit (10) for airborne application. The basic working principle of munition arming unit (10) is described below.

Basically, the munition (M) is turned ON from the drone (not shown) through the umbilical connector (8). The detonation scheme of the bomb is configured from drone through communication commands. The possible ways of detonation are, timer-based, an impact switch or through an accelerometer sensor. On power up, the device performs the self-test (built-in-test) and sends the health status and the detonation option selected. When the bomb is released from the drone, an ARM pulse is generated after 1-3 seconds from umbilical snap. In one embodiment, when the bomb is released from the drone, an ARM pulse is generated after 2 seconds from umbilical snap. The FIRE pulse is generated depending on the detonation option selected or through self-destruction timer after a stipulated time is elapsed.

Further, in the present invention, the battery (6) mounted in the nose assembly (1) of munition (M) can sometimes get activated during transportation. To prevent any discharge of the battery (6) which can otherwise result in mission failure, a feature is implemented by which the munitions (M) get powered off after 3 seconds on detecting umbilical snap after power up. A timer-based feature and the micro electro-mechanical system (MEMS) based 3 axes accelerometer is also integrated to provide flexibility in detonating on various terrains. A reliable arming delay of 1-3 seconds is provided to ensure that the bomb has travelled a safe distance after bomb release. In one embodiment, a reliable arming delay of 2 seconds is provided to ensure that the bomb has travelled a safe distance after bomb release. Once the bomb is armed, it is detonated by timer or impact or micro electro-mechanical system (MEMS) accelerometer or self-destruction timer of 21-23 seconds. In one embodiment, once the bomb is armed, it is detonated by timer or impact or micro electro-mechanical system (MEMS) accelerometer or self-destruction timer of 22 seconds. If the bomb is dropped and it is not armed, the bomb can be handled safely by inserting the cap (14) on the safety switch.

Figure 6 shows the flowchart of the working method steps of safety and arming mechanism (SAM) of munition arming unit (10).

In step 1, a mission to detonate the bomb starts. In step 2, the munition (M) and the drone (not shown) are connected with umbilical connector (8). In steps 3 and 4, the bomb is turned ON by turning ON the relay wherein the bomb is activated by on-board battery (6) mounted in the nose assembly (1).

After turning ON the bomb, the health query of the bomb is performed by enabling the periodic health response in step 5. In step 6, if the health is OK, accelerometer is enabled if needed in step 7. By enabling the accelerometer, the proper acceleration of the bomb has been measured.

After enabling the accelerometer, turning towards portion (B) of flowchart in figure 6 wherein in step 8, the register status is DISARMED. Also, the munition (M) and the drone are connected with umbilical connector (8) in step 9.

In step 10, by generating the ARM pulse, the register is updated to arm the safety and arming mechanism (SAM) of munition arming unit (10) by holding the bomb in standby mode for ARMING the safety and arming mechanism (SAM).

In step 11, the bomb is in standby mode for releasing and the bomb is released in step 12. If the munition (M) and the drone are umbilically snapped in step 12a and the health status response has been received in step 13, the relay has been turned off and the communication of the munition (M) and drone is disconnected in steps 14 and 15. At last, in step 16, the mission has been aborted by generating the pulse ABORT.

Returning to step 12, after releasing the bomb, if the bomb snap is detected in step 12b, the safety timer of 2 seconds starts in step 18. Otherwise, go to step 11 again to release the bomb. If the safety timer of 2 seconds is elapsed in step 19, the safety and arming mechanism (SAM) of munition arming unit (10) arms and self-destruct timer starts in step 20. Otherwise, repeat the method steps 14-16.

Returning to step 12a, if the munition (M) and the drone are not umbilically snapped and also, if the safety timer is not elapsed in step 19, repeat the method steps 14-16. In other case, if the munition (M) and the drone are not umbilically snapped and if the safety timer is elapsed in step 19, repeat the method step 20 and further steps of portion (D).

Returning to step 13, if the munition (M) and the drone are umbilically snapped in step 12a and the health response has not been received in step 13, repeat the method steps of portion (C) that is, repeat the method step 20 and further steps of portion (D).

After arming the safety and arming mechanism (SAM) of munition arming unit (10) and starting the self-destruct timer in step 20, turning towards the portion (D) of flowchart in figure 6, there are four options in steps 21-24. The impact switch and the G-switch are closed in steps 21 and 22. Also, the accelerometer is enabled in step 23. Further, if the self-destruct timer is elapsed in step 24, the bomb is directly detonated in step 27 and the mission has been finished in step 28.

Otherwise, to detonate the bomb safely, take the statuses of steps 21 and 22 and OR it by using OR GATE 25.

The OR gate is a digital logic gate that executes logical disjunction – it works according to the truth table. A HIGH output results if one or both the inputs to the gate are HIGH. If none of the inputs is high, a LOW output results. The truth table for OR GATE is given below in table 1:

TABLE 1
INPUTS OUTPUT
A B Y
LOW LOW LOW
LOW HIGH HIGH
HIGH LOW HIGH
HIGH HIGH HIGH

In particular, the results for combination of inputs of OR GATE 25 are given below in table 2:
TABLE 2
INPUTS OUTPUT
Status of Step 21 Status of Step 22 Output of OR GATE 25
LOW LOW LOW
LOW HIGH HIGH
HIGH LOW HIGH
HIGH HIGH HIGH

NOTE: Considering the status of closed impact switch in step 21 is HIGH and otherwise LOW. Similarly, considering the status of closed G-switch in step 22 is HIGH and otherwise LOW.

From the above Table 2, it gets that the output of OR GATE 25 is LOW, only when both the impact switch and G-switch are not closed i.e. the status is LOW and the output of OR GATE 25 is HIGH, when status of any one of impact and G-switches is closed i.e. HIGH.

Further, the outputs of OR GATE 25 are again OR with the status of step 23 using OR GATE 26. In step 23, the accelerometer is enabled and therefore, consider the status of step 23 is always HIGH. The results for combination of inputs of OR GATE 26 are given in below table 3:
TABLE 3
INPUTS OUTPUT
Output of OR GATE 25 Status of Step 23 Output of OR GATE 26
LOW HIGH HIGH
HIGH HIGH HIGH
HIGH HIGH HIGH
HIGH HIGH HIGH

From the above Table 3, it gets that the output of OR GATE 26 is always HIGH, as the status of accelerometer in step 23 is always high.

Further, as the output is OR GATE 26 is HIGH, the bomb is detonated in step 27 and the mission has been finished in step 28.

Returning to step 2, if the munition (M) and the drone are not connected with umbilical connector (8), wait until they are connected in step 2a. Once they are connected, repeat the method steps from step 3 and further.

Returning to step 6, if the health is not OK, there are three options. Firstly, in step 6a, the iterations are done to perform the health query for enabling the periodic health response in step 5. Secondly, in step 6b, overriding the health status of step 6 and enabling the accelerometer if needed of step 7 for measuring the proper acceleration of bomb, repeat the method steps from portion (B). Thirdly, at the end of iterations, the bomb is turned OFF by turning OFF the relay in step 6c. The communication of the munition (M) and drone is disconnected in step 6d and the mission has been aborted by generating the pulse ABORT in step 6e.

Returning to step 8, if the status of register is not DISARMED, update the register status to DISARM in step 8a and repeat the method steps from step 8 of portion (B) and further.

Returning to step 9, if the munition (M) and drone are not connected with umbilical connector (8), the bomb is turned OFF by turning OFF the relay in step 9a. The communication of the munition (M) and drone is disconnected in step 9b and the mission has been aborted by generating the pulse ABORT in step 9c.

Thus, the above-mentioned description can be summarized as, a method for working of munition arming unit (10) with safety and arming mechanism (SAM), wherein the method comprises:
- turning ON a munition (M) from a drone through an umbilical connector (8);
- configuring the detonation scheme from the drone through communication commands;
- performing the self-test and/or built-in-test on power up;
- sending the health status;
- selecting the detonation option;
- generating an ARM pulse when the bomb is released from the drone;
- generating a FIRE pulse depending on the detonation option selected and/or through self-destruction timer after a stipulated time is elapsed;
wherein the ARM pulse is generated after 2 seconds from umbilical snap of the munition (M) and the drone.

Thus, the present invention relates to a munitions arming unit for airborne application. The munitions arming unit (10) with a Safety and Arming mechanism (SAM) has a primary function to provide arming and detonation of the warhead whenever intended. To avoid any potential for any mishap, to both, airborne platform (drone) and personnel, a novel safety device is designed to ensure that the weapon is in “armed” condition only when desired and in “safe” condition at all other times. This safety device is an integral part of the munitions to prevent any inadvertent firing of the munitions. A novel design of munitions arming unit (10) with robust safety mechanism for munitions to prevent any inadvertent firing during handling and operation.

APPLICATION AND/OR ADVANTAGES:

A munitions arming unit (10) for airborne application of the present invention provides the following advantages:
- A safety cap (14) is provided on the munitions surface. It shorts the igniter terminal of safety and arming mechanism (SAM) for safe handling during mounting of the munitions (M) on the platform (Drone) and while transporting them. The two terminals are shorted by a cap (14) for safe handling.
- The warhead (Explosive’s) igniter terminals are also brought out to the umbilical connector (8) to ensure that the munition (M) is safe as long as it is connected to the drone.
- The battery (6) mounted in nose assembly (2) of munition (M) can sometimes get activated during transportation. To prevent any discharge of the battery (6) which can otherwise result in mission failure, a feature is implemented by which the munitions (M) get powered off after 3 seconds on detecting umbilical snap after power up.
- A timer-based feature and the micro electro-mechanical system (MEMS) based 3 axes accelerometer is also integrated to provide flexibility in detonating on various terrains.
- A reliable arming delay of 2 seconds is provided to ensure that the bomb has travelled a safe distance after bomb release.
- Once the bomb is armed, it is detonated by timer or impact or micro electro-mechanical system (MEMS) accelerometer or self-destruction timer of 22 seconds.
- If the bomb is dropped and it was not armed, the bomb can be handled safely by inserting the cap on the safety switch.
- The safety and arming mechanism (SAM) of munition arming unit (10) is relatively simple in construction and can be accommodated in the miniaturized space available within the bomb shell.
- To avoid any potential for any mishap, to both, airborne platform (drone) and personnel, a novel munition arming unit (10) with safety device is designed to ensure that the weapon is in “armed” condition only when desired and in “safe” condition at all other times.
, Claims:1. A munitions arming unit (10) for airborne application, wherein the munition arming unit (10) comprises:
a Safety and Arming mechanism (SAM) to provide arming and detonation of the warhead whenever intended;
an umbilical connector (8) for coupling a munition (M) and a drone;
a safety cap (14) provided on the surface of the munition (M);
a timer-based feature;
a micro electro-mechanical system (MEMS) based 3 axes accelerometer;
wherein the umbilical connector (8) comprises a microcontroller capable of communicating serially with the drone and the safety and arming mechanism (SAM);
wherein the safety cap (14) shorts the igniter terminal of safety and arming mechanism (SAM) of munition arming unit (10) for safe handling during mounting of the munitions (M) on the drone and while transporting them.

2. The munition arming unit (10) as claimed in claim 1, wherein the safety cap (14) is divided into two parts comprising a shorting plug (14a) and a receptacle (14b).

3. The munition arming unit (10) as claimed in claim 1, the igniter terminals of warhead of explosive contained in the charge (9) of warhead assembly (2) are brought out to the umbilical connector (8).

4. A munition (M) comprising a munition arming unit (10) with safety and arming mechanism (SAM) as claimed in claim 1, wherein the munition (M) comprises:
- a nose assembly (1);
- a warhead assembly (2); and
- a rear assembly (3);
wherein the structures for nose assembly (1) and rear assembly (3) are made up of aluminium alloy; and
wherein the structure of warhead assembly (2) is made up of EN-24 steel material.

5. The munition (M) as claimed in claim 4, wherein the nose assembly (1) comprises a battery (6), a safety connector (7), a G-switch (4) of 50 g and a Printed Circuit Board (PCB) (5).

6. The munition (M) as claimed in claim 4, wherein the warhead assembly (2) comprises a safety and arming mechanism (SAM) of munition arming unit (10) and a charge (9) filled with an explosive.

7. A method for working of a munition arming unit (10) with safety and arming mechanism (SAM) as claimed in claim 1, wherein the method comprises:
- turning ON a munition (M) from a drone through an umbilical connector (8);
- configuring the detonation scheme from the drone through communication commands;
- performing the self-test and/or built-in-test on power up;
- sending the health status;
- selecting the detonation option;
- generating an ARM pulse when the bomb is released from the drone;
- generating a FIRE pulse depending on the detonation option selected and/or through self-destruction timer after a stipulated time is elapsed;
wherein the ARM pulse is generated after 2 seconds from umbilical snap of the munition (M) and the drone.

8. The method for working of the munition arming unit (10) as claimed in claim 7, wherein the munition (M) gets powered OFF after 3 seconds on detecting the umbilical snap between munition (M) and the drone after power up.

9. The method for working of the munition arming unit (10) as claimed in claim 7, wherein an arming delay of 2 seconds is provided to measure the travelled distance of the bomb after releasing.

10. The method for working of the munition arming unit (10) as claimed in claim 7, wherein after arming, the bomb is detonated by timer or impact or micro electro-mechanical system (MEMS) accelerometer or self-destruction timer of 22 seconds.