Description:FIELD OF THE INVENTION:

The present invention generally relates to the Control Actuation System for deploying the fins of missile or the like flying object. Particularly, the invention relates to the design and development of control actuation system for ATGM (Anti-tank Guided Missile).

BACKGROUND OF THE INVENTION:

Control actuation system (CAS) is a guidance component of the missile or the flying object for moving and controlling of the mechanism of the missile or the flying object. Actuation systems are the elements of control systems which are responsible for transforming the output of a microprocessor or control system into a controlling action on a machine or device. The control actuation system is combined with on-board-computer or microcontroller and controlled the mechanism of the missile. There are many types of control actuation system described in the prior arts. Some existing prior arts are as follows:

US patent publication no. US 2022/0178665A1 discloses control plate-based control actuation system which have a control plate with at least four fin linkages for connecting at least four fins to the control plate; and three actuators configured to move the control plate to produce movement in two or more of the at least four fins. The system produces roll, pitch, and yaw moments for the moving object using three actuators acting on the control plate and thus moving two or more of the at least four fins all with no loss of performance as compared to systems with four actuators.

US patent no. US7475846B2 discloses fin retention and deployment mechanism. It provides for the deployment of aerodynamic control surfaces on command without the need for an additional actuation device or control circuitry separate from the actuator that controls the angle of the fins during flight. The actuator that is already required for operation of the control surfaces after deployment initiates the deployment of the fins, as well. A latch mechanism comprises a retaining member and a lath, which engages the retaining member enabling a biasing mechanism to force the fins from a stowed position to a fully deployed position.

US patent no. US5293811A discloses missile control fin actuator system. The missile control fin actuator produces rotation of a control fin output shaft which is embodied in a pressure actuator, including a housing and a piston slidable within the housing to define at least two pressure chambers within the housing. A rolling diaphragm seal is placed between the piston and the housing wall, the rolling diaphragm seal providing a pressure seal between the pressure chambers. A push rod is connected to the piston and extends out of the housing. Means is provided for controllably pressurizing the two pressure chambers to cause the piston to slide within the housing. There is also provided means for connecting the push rod to a control fin output shaft.

US patent no. US9366514B1 discloses system, method and computer program product for providing for a course vector change of a multiple propulsion rocket propelled grenade. The projectile system comprises a gun-fired projectile having a body, at least one tail fin, a motor firing during a first flight phase and during a second flight phase and at least one controllable canard. The projectile system includes one or more processors configured to determine a turn maneuver profile to a target during the first flight phase, produce control signals to destabilize the body, create a pitch attitude change for the turn maneuver profile and effectuate a turn of the projectile in a direction corresponding to the turn maneuver profile during the first flight phase. The processors control the motor to start the second flight phase to the target after the turn.

The drawbacks in the above existing prior arts are that the mechanism of deploying of fins does not work properly and also it takes long time for deploying the fins. Therefore, the present invention provides a control actuation system for the moving and controlling the mechanism of missile. The novel CAS can deploy the fins very fast and provides maneuverability and control over the missile.

Thus, the aim of present invention is to solve all these issues by aiming to provide a control actuation system for ATGM.

OBJECTIVES OF THE INVENTION:

The principal object of the present invention is to provide a control actuation system for ATGM.

Another main object of the present invention is to design and develop the control actuation system for ATGM (Anti-Tank-Guided-Missile) for utilizing of controlling the flight.

Another object of the invention is to provide TVC blades for deflecting to get desired TVC effect.

Another object of the invention is to provide a self-locked control actuation system (CAS) for missile.

Yet another object of the invention is to provide novel control actuation system which provides maneuverability and control for missile flight.

SUMMARY OF THE INVENTION:

Accordingly, the present invention provides a control actuation system for ATGM. The control actuation system (CAS) comprises four blades/fins each blade is equipped with individual motor, and a lead screw. The CAS includes mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC). Once the motor rotates, its rotary motion is converted into linear motion which is being transferred over the linkages by the linear movement of nut over the lead screw. The said CAS provides maneuverability and controls over the missile flight.

In one aspect of the present invention, the present invention provides a control actuation system for ATGM. A control actuation system (100) for ATGM wherein the control actuation system is an electro-mechanical actuation module comprising a plurality of control surfaces or fins (101) are equipped with individual motor and a lead screw (102);
wherein the control surfaces or fins (101) are deployed after activation of propulsion system;
wherein the CAS (100) ensures the maneuverability and control the missile flight.

The said CAS (100) comprises mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC).

Four control surfaces or fins (101) are assembled at one end of the CAS body (103).

The motor is a brushless direct current (BLDC) motor;
wherein the control surfaces or fins (101) are equipped with BLDC motors along with encoder assembly.

The control surfaces or fins (101) are folded inside the missile body or CAS (100);
wherein the control surfaces or fins (101) are loaded with compression spring.

The said fins / control surfaces (101) are TVC blades;
wherein the TVC assembly and fins / control surfaces (101) are connected together by four-bar mechanism (104) to make the system synchronized.

The control surfaces or fins (101) are deployed by the spring-loaded plunger;
wherein spring-loaded plunger pushes the control surfaces / fins (101) for deployment and get locked by same plunger.

The control surfaces / fins (101) are deployed and makes 105⁰±15 degree angle with the missile axis.

The control surfaces / fins (101) are deployed in 60 milliseconds.

In another aspect of the present invention, the present invention provides a method for control actuation system (100), wherein the CAS (100) comprises mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC);
wherein the method comprises steps of:

- initially stowed positioning the control surfaces / fins (101);
- rotating the motor in rotary motion;
- converting rotary motion into linear motion;
- transferring the linear motion over the linkages by the linear movement of nut over the lead screw (102);
- deflecting the fins and TVC blade at same angle;
- pushing the control surfaces or fins (101) by spring-loaded plunger;
- deploying the control surfaces or fins (101) at 105⁰±15 degree angle with the missile axis in 60 milliseconds and locking by same compression spring.

Thus, the aim of the present invention is to design a novel control actuation system for ATGM for operating and controlling the ATGM.

The above description merely is an outline of the technical solution of the present disclosure; 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 more clear and easy to understand, specific embodiments of the present invention will be described in detail below.

BRIEF DESCRIPTION OF DRAWINGS:

The accompanying drawing which is incorporated herein constitute a portion of this specification and illustrate exemplary practices according to the invention which, together with the general description above and the detailed description set forth below will serve to explain the principle of the invention wherein:

Fig. 1 shows the schematic perspective view of control actuation system (CAS) (100) of the present invention.

Fig. 2 shows the perspective angled view of control actuation system (CAS) (100) of the present invention.

Fig. 3 shows the side view of the control actuation system (CAS) (100) of the present invention.

Fig. 4 shows the schematic perspective view of lead screw (102) of control actuation system (CAS) (100) of the present invention.

Fig. 5 shows the front view of control actuation system (CAS) (100) of the present invention.

DETAILED DESCRIPTION OF THE INVENTION:

Accordingly, the present invention provides a control actuation system (CAS) for ATGM (Anti-Tank-Guided-Missile). Generally, the actuator system includes two sub-systems: the electronic control unit and the electromechanical actuator. The position command signals the electronic control unit, which in turn provides input voltage to drive the electric motor in the electromechanical actuator. Depending upon the speed and torque requirements, the motor which is coupled with a gearbox and lead-screw arrangements to actuate mechanical linkages. These linkages control the missile fin and position the missile towards the identified target.

The Control Actuation Systems (CAS) controls the position of the missile fins in response to steering commands from the flight computer. The typical CAS consists of actuators and associated control electronics all integrated and assembled in the inner body of the CAS of the missile.

The present invention discloses a control actuation system for ATGM. It provides the novel design and development of Control Actuation System.

In one aspect of the present invention, the present invention provides a Control Actuation System (CAS) (100) of missile. The CAS (100) is an Electro-Mechanical Actuation module having independently actuated fins.

Fig. 1-5 show the novel design of control actuation system (CAS) (100). The said CAS (100) comprises four blades/fins (101) each blade is equipped with individual motor, a lead screw (102), outer body of CAS or CAS body (103) and parallelogram mechanism of four-bar linkage (104).

The CAS (100) also comprises On-board computer which is integrated in the inner body (not shown in fig.) of the CAS (100). The onboard computer (OBC), provided by the control board, manage all the tasks taking place within the missile. The processor needs to interface with various sensors, actuators present onboard to acquire data to perform its activities and responds accordingly through actuators. The CAS (100) includes mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC).

In one embodiment, control actuation system (100) of the missile is an electro-mechanical actuation module having independently actuated fins (101) of NACA symmetric aerofoil. The control actuation system (CAS) has following critical subassemblies.

I. Tail deploying mechanism.
II. TVC blade
III. BLDC Motors with encoder assembly
IV. Linkage between Tail, TVC Blade & Motor.
V. Actuation control Unit PCB with Flexi rigid interface with OBC

The blades/fins (101) are arranged at one end of the CAS (100). In one embodiment, the fins or blades (101) are arranged at 90º apart from each other. In one embodiment, the blades (101) are TVC blades. The blades/fins (101) are deflecting to get the desired TVC effect. TVC assembly and fin/control surface are connected together by four-bar mechanism which make the system synchronized.

Each control surface or fins (101) are equipped with a motor along with encoder assembly. In one embodiment the said motor is Brushless DC motors (BLDC motor).

The linkage used in CAS (100) as shown in fig. 1 to show how rotary motion of motor is converted into linear motion and then it is transferred to the links to get required deflection of tail and TVC. Lead screw (102) is rigidly mounted on the motor shaft. Once motor rotates, its rotary motion pushes the nut in linear direction.

Tail link hinged with nut and fixed with tail gives angular deflection. Correspondingly, the same amount of angular deflection on TVC link which is fixed with TVC blade is transferred by connecting link. Deflection of tail and TVC are same as they are following parallelogram-four bar linkage mechanism (104). The ACU PCB is a 4-channel actuator servo control unit which drives the four motors independently after receiving the independent commands from the OBC. A quadrature incremental encode is utilized for obtaining the position feedback from the motors. The control system is designed with operational bandwidth of 30 Hz.

In principle the novel design of CAS (100) provides maneuverability and control over the missile. Initially the tails are folded inside the missile body (inside CAS (100)). These are in loaded condition with compression spring. A lead screw (102) is attached over the motor shaft and a nut (not shown in fig.) which is moving over the lead screw (102). The four-bar linkage is connected with the nut for the power transmission.

The control actuation system can be summarized as:
A control actuation system (100) for ATGM wherein the control actuation system is an electro-mechanical actuation module comprising a plurality of control surfaces or fins (101) equipped with individual motor and a lead screw (102);
wherein the control surfaces or fins (101) are deployed after activation of propulsion system;
wherein the CAS (100) ensures the maneuverability and control the missile flight.

Working principle of CAS (100):

In another aspect, present invention provides a method for deploying the TVC blades of the Control actuation system (100). The CAS (100) controls the flight of ATGM (Anti-Tank-Guided-Missile).

Initially the control surfaces / fins (101) are at stowed position i.e. folded inside the CAS body (103). Once the motor rotates, its rotary motion is converted into linear motion which is being transferred over the linkages by the linear movement of nut over the lead screw (102). This action provides same angle of deflection at both the points i.e. at the fin & TVC blade. The lead screw (102) and nut of the CAS (100) helps to lock the control surfaces into place such that they remain in place even in the presence of extremely high aerodynamics forces subjected there upon.

A spring-loaded plunger pushes the control surfaces / fins (101) by means of spring force for the deployment and get locked by the same plunger (self-locked) as it arrests its back-word motion which prevent the control surfaces / fins (101) to recoil. In one embodiment, the spring-loaded plunger comprises one compression spring for the deployment of control surfaces / fins (101). The same compression spring is used for locking the fins (101). After deploying the control surfaces / fins (101), it makes at angle with the missile axis. In one embodiment, after deploying the control surfaces / fins (101), it makes 105º angle with the missile axis.

Once missile comes out from the launch tube after activation of propulsion system, the tails are deployed very fast and self-locked. In one embodiment, the tails are deployed in 60 milliseconds. After that actuation system function properly to avoid drop down of missile on the ground. The design has been carried out for the tail deflection of ± 15 deg.

The method for control actuation system can be summarized as:
A method for control actuation system (100), wherein the CAS (100) comprises mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC);
wherein the method comprises steps of:
- initially stowed positioning the control surfaces / fins (101);
- rotating the motor in rotary motion;
- converting rotary motion into linear motion;
- transferring the linear motion over the linkages by the linear movement of nut over the lead screw (102);
- deflecting the fins and TVC blade at same angle;
- pushing the control surfaces or fins (101) by spring-loaded plunger;
- deploying the control surfaces or fins (101) at 105º± 15 degree angle with the missile axis in 60 milliseconds and locking by same compression spring.
, Claims:
1. A control actuation system (100) for ATGM wherein the control actuation system is an electro-mechanical actuation module comprising a plurality of control surfaces / fins (101) are equipped with individual motor and a lead screw (102);
wherein the control surfaces or fins (101) are deployed after activation of propulsion system;
wherein the CAS (100) ensures the maneuverability and control the missile flight.

2. The control actuation system (100) as claimed in claim 1, wherein the CAS (100) comprises mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC).

3. The control actuation system (100) as claimed in claim 1, wherein four control surfaces or fins (101) are assembled at one end of the CAS body (103).

4. The control actuation system (100) as claimed in claim 1, wherein the motor is a brushless direct current (BLDC) motor;
wherein the control surfaces or fins (101) are equipped with BLDC motors along with encoder assembly.

5. The control actuation system (100) as claimed in claim 3, wherein the control surfaces or fins (101) are folded inside the missile body or CAS (100);
wherein the control surfaces or fins (101) are loaded with compression spring.

6. The control actuation system (100) as claimed in claim 1, wherein the said fins / control surfaces (101) are TVC blades;

wherein the TVC assembly and fins / control surfaces (101) are connected together by four-bar mechanism (104) to make the system synchronized.

7. The control actuation system (100) as claimed in claim 1, wherein the control surfaces or fins are deployed by the spring-loaded plunger;
wherein spring-loaded plunger pushes the control surfaces / fins (101) for deployment and get locked by same plunger.

8. The control actuation system (100) as claimed in claim 6, wherein the control surfaces / fins (101) are deployed and makes 105⁰±15 degree angle with the missile axis.

9. The control actuation system (100) as claimed in claim 1, wherein the control surfaces / fins (101) are deployed in 60 milliseconds.

10. A method for control actuation system (100), wherein the CAS (100) comprises mechanical assembly and electrical system with PID based actuation control unit for executing the command received from On-board Computer (OBC);
wherein the method comprises steps of:

- initially stowed positioning the control surfaces / fins (101);
- rotating the motor in rotary motion;
- converting rotary motion into linear motion;
- transferring the linear motion over the linkages by the linear movement of nut over the lead screw (102);
- deflecting the fins and TVC blade at same angle;
- pushing the control surfaces or fins (101) by spring-loaded plunger;
- deploying the control surfaces or fins (101) at 105⁰±15 degree angle with the missile axis in 60 milliseconds and locking by same compression spring.