A driving and control method for changing the twist shape of an airfoil

Abstract

This invention discloses a driving and control method for changing the torsional shape of an airfoil, belonging to the field of variator aircraft structural design technology. The invention sets a hinge point at a spanwise position on the front and rear spars of the airfoil. The section from the wing root to the hinge point is a fixed section, and the section from the hinge point to the wingtip is a torsional deformation section. The method includes a driving system comprising a gear screw, a nut, a stop block, a support block, a cable displacement sensor, and a driving device. The torsional deformation angle of the airfoil is measured by the cable displacement sensor arranged on the front and rear spars, which measures the movement distance of the gear screw relative to the nut on the deformed spars. The deflection angles of the front and rear spars are calculated based on the height of the spars web, and the torsional shape of the airfoil is obtained by combining this with the chordal distance between the front and rear spars. This invention achieves active torsional deformation of the airfoil, effectively improving the roll maneuverability of the aircraft, improving the distribution of aerodynamic loads, reducing the load at the wing root, and optimizing the aerodynamic characteristics of the airfoil.

Description

Technical Field

[0001] This invention belongs to the field of variator aircraft structural design technology, specifically relating to a driving and control method for changing the twist shape of an airfoil. Background Technology

[0002] Current research on vari-engine aircraft mainly focuses on altering wing area, wingspan, wing chord length, wing sweep angle, and wing leading and trailing edge camber. To effectively improve wing roll maneuverability and static aeroelasticity, researchers are conducting in-depth studies on wing torsional deformation technology. Adjusting the wing's torsional shape can effectively improve the aircraft's roll maneuverability and also effectively improve aileron reaction and static aeroelasticity. By changing the distribution of the wing's leading edge torsion angle, the aerodynamic load distribution of the wing can be improved, and the load at the wing root can be reduced, thereby effectively increasing the structural lifespan. Furthermore, active wing torsional deformation combined with leading and trailing edge deflection increases the wing's deformation combinations. Summary of the Invention

[0003] This invention proposes a driving and control method for changing the torsional shape of an airfoil. This method can achieve active torsional deformation of the airfoil, effectively improve the roll maneuverability of the aircraft, improve the distribution of aerodynamic loads, reduce the load at the airfoil root, and optimize the aerodynamic characteristics of the airfoil.

[0004] This invention is implemented as follows:

[0005] A driving and control method for changing the torsional shape of an airfoil, characterized in that a hinge point is set at a certain spanwise position on the front and rear spars of the airfoil, the section from the wing root to the hinge point is a fixed section, and the section from the hinge point to the wingtip is a torsional deformation section; the driving system includes a gear screw, a nut, a stop block, a support block, a cable displacement sensor, and a driving device; the control method of the driving system is as follows:

[0006] The first step is to set the relative positions of the support blocks and nuts on the front and rear wing spars to the initial state when the wing is not twisted. At this time, the output value l of the cable displacement sensor on the front and rear wing spars is set. i0 Set as the initial reading, i.e., l 10 =l 20 =0; Set the torsion angle α at the span m of the torsional deformation section spar, and calculate the value l1 that the sensor should output after torsional deformation using the formula. ’ With l2 ’ ;

[0007] The second step is to read the output values ​​of the sensors on the front and rear wing spars in the current state to determine the driving status of the wing drive system; if the output value of the front spars sensor is l1 = l1 ’ And the output value of the rear beam sensor is l2 = l2 ’The wing does not need to change its flight state; if the front spar sensor output value l1 < l1 ’ Furthermore, the output value of the rear beam sensor, l2 > l2 ’ The wing is positively driven (front spar deflects upward, rear spar deflects downward); if the front spar sensor output value l1 > l1 ’ And the output value of the rear beam sensor l2 < l2 ’ The wing is negatively driven (the front spar deflects downwards and the rear spar deflects upwards);

[0008] Thirdly, if a change in drive state is required, the stepper motors on the front and rear wing spars are simultaneously activated via the control system. The driving force is transmitted to the gear screw through the first, second, and third stage transmission shafts, driving the front and rear wing spars to deflect simultaneously. The output values ​​of the cable displacement sensors on the front and rear wing spars are respectively equal to l1 ’ With l2 ’ At that time, the wingtip torsional deformation is completed.

[0009] Furthermore, the bottom surface of the cable displacement sensor is attached to the web of the torsional deformation section spar, and the side is fixed to the lower edge strip of the torsional deformation section spar. The measuring head of the cable displacement sensor is fixed to the side of the lower edge strip of the fixed section spar. The torsional deformation angle of the wing is measured by the cable displacement sensors arranged on the front and rear spars. The distance the gear screw on the deformed spar moves relative to the nut is obtained. The deflection angle of the front and rear spars is calculated based on the height of the spar web. The torsional shape of the wing is obtained by combining the chordal distance between the front and rear spars.

[0010] Furthermore, the web of the fixed section and the torsional deformation section are hinged by single and double lugs. The upper and lower flanges on the left and right sides of the web are connected by four gear screws. The thread direction of the upper flange gear screw is opposite to that of the lower flange gear screw. When the gear screw is driven to rotate by the motor, the gear screws of the upper and lower flanges will generate axial forces in opposite directions, forming a couple, which will cause the spar of the torsional deformation section to deflect around the hinge point. The front and rear spars of the wing deflect upward and downward around the hinge point, respectively. The skin on the upper and lower surfaces of the wing restricts the distance between the front and rear spar flanges to remain unchanged, causing the wing to undergo torsional deformation.

[0011] Furthermore, in the aforementioned drive system: a nut is fixed to the flange of the torsional deformation section of the beam, with the bottom surface of the nut flush with the beam cross-section; a support block is fixed to the flange of the fixed section of the beam, with the bottom surface of the support block flush with the beam cross-section; a gear screw passes through the circular through hole of the support block, with the circular boss contacting the bottom surface of the support block, and the threaded section fitting the nut; a stop block is fixed to the flange of the fixed section of the beam, allowing the smooth end of the gear screw to extend into the circular recess of the stop block; wherein, the nut, the circular through hole on the support block, the gear screw, and the circular recess on the stop block are coaxial; when the gear screw rotates, the support block prevents the gear screw from axially displacing, and the stop block prevents the gear screw from axially displacing and radially swaying.

[0012] Furthermore, the drive unit includes a motor, a primary drive shaft, a secondary drive shaft, and a tertiary drive shaft; the motor and each drive shaft are mounted on the fixed section wing beam; after the motor starts, the four gear screws are synchronously subjected to the same driving torque through the drive shafts; the bottom surface of the pull rope displacement sensor is attached to the web of the torsional deformation section wing beam, the side is fixed to the lower edge strip of the torsional deformation section wing beam, and the measuring pull head is fixed to the lower edge strip of the fixed section wing beam, used to measure the movement distance of the gear screws on the front and rear beams relative to the nuts.

[0013] Furthermore, drive units are installed on the front and rear wing spars respectively, and the front and rear spars are driven in coordination. When the drive units drive the front and rear wing spars to deflect up and down around the hinge point respectively, the skin on the upper and lower surfaces of the wing restricts the distance between the front and rear spars edge strips to remain unchanged, causing the wing to undergo torsional deformation.

[0014] Furthermore, the gear screw is divided into six sections: the first section is a threaded section that is adapted to the nut; the second section is a cylindrical section; the third section is a circular boss, the top surface of which contacts the bottom surface of the support block; the fourth section is a cylindrical section; the fifth section is a gear, which is used to cooperate with the drive device to transmit force; and the sixth section is a cylindrical section, the end of which extends into the circular recess of the stop block.

[0015] Furthermore, the outer contour of the nut is a quadrangular prism, one side is fixedly connected to the upper and lower edge strips of the torsional deformation section of the wing beam, the adjacent side is fixedly connected to the web plate, the nut is adapted to the threaded section of the gear screw, and the thread direction of the nut at the upper and lower edge strips is opposite.

[0016] Furthermore, the outer contour of the support block is a quadrangular prism, with one side fixed to the upper and lower edge strips of the fixed section of the wing beam, and the adjacent side fixed to the web plate; a circular through hole is provided on the bottom surface of the support block, and the gear screw passes through the circular through hole so that the circular boss of the gear screw contacts the bottom surface of the support block.

[0017] Furthermore, the outer contour of the stop block is the same as that of the support block. One side is fixed to the upper and lower edge strips of the fixed section of the wing beam, and the adjacent side is fixed to the web plate. A circular recess is provided on one of its bottom surfaces, so that the smooth end of the gear screw can be inserted into the recess, which prevents the screw from axially displacing and from radially swaying.

[0018] The advantages of this invention compared to the prior art are as follows:

[0019] This invention proposes a driving and control method for changing the torsional shape of a double-spar wing. This method facilitates the active alteration of the wing's torsional shape, effectively improving the aircraft's roll maneuverability, improving the distribution of aerodynamic loads, reducing wing root loads, and optimizing the wing's aerodynamic characteristics. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of wing torsional deformation in a driving and control method for changing the torsional shape of an airfoil according to the present invention.

[0021] Figure 2 This is a schematic diagram of the differential deflection of the front and rear beams in a driving and control method for changing the torsional shape of an airfoil according to the present invention.

[0022] Figure 3 This is a schematic diagram showing the connection between the fixed section and the torsional deformation section of the wing spars in a driving and control method for changing the torsional shape of an airfoil according to the present invention.

[0023] Figure 4 This is a schematic diagram of the installation of the cable displacement sensor in the driving and control method for changing the torsional shape of an airfoil according to the present invention.

[0024] Figure 5 This is a schematic diagram of sensor measurement in a driving and control method for changing the twist shape of an airfoil according to the present invention;

[0025] Figure 6 This is a flowchart of a driving and control method for changing the twist shape of an airfoil according to the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and effects of this invention clearer, the invention is further described in detail below through examples. It should be noted that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0027] This invention proposes a driving and control method for changing the torsional shape of an airfoil, which can achieve active torsional deformation of the airfoil, such as... Figure 1 As shown. A hinge point is set at a spanwise position on the front and rear spars of the wing. The section from the wing root to the hinge point is the fixed section, and the section from the hinge point to the wingtip is the torsional deformation section. The webs of the fixed and torsional deformation sections are hinged by single and double lugs. The upper and lower flanges on both sides of the web are connected by four gear screws, with the thread direction of the upper flange gear screws opposite to that of the lower flange gear screws. When the gear screws are rotated by a motor, the gear screws of the upper and lower flanges will generate axial forces in opposite directions, forming a torque, which causes the spars of the torsional deformation section to deflect around the hinge point; the front and rear spars of the wing deflect upward and downward around the hinge point respectively. The skin of the upper and lower surfaces of the wing restricts the distance between the front and rear spars, causing the wing to undergo torsional deformation, as shown. Figure 2 As shown.

[0028] The drive system of this invention mainly consists of a gear screw, a nut, a stop block, a support block, a pull rope displacement sensor, and a drive device, such as... Figure 3As shown. A nut is fixed to the flange of the torsional deformation section of the beam, with its bottom surface flush with the beam cross-section. A support block is fixed to the flange of the fixed section of the beam, with its bottom surface flush with the beam cross-section. A gear screw passes through a circular through-hole in the support block, with a circular boss contacting the bottom surface of the support block, and its threaded section fitting the nut. A stop block is fixed to the flange of the fixed section of the beam, allowing the smooth end of the gear screw to extend into the circular recess of the stop block. The nut, the circular through-hole in the support block, the gear screw, and the circular recess in the stop block are coaxial. When the gear screw rotates, the support block prevents axial displacement, and the stop block prevents both axial displacement and radial oscillation. The bottom surface of a pull-string displacement sensor is attached to the web of the torsional deformation section wing beam, its side is fixed to the lower edge of the torsional deformation section wing beam, and the measuring head is fixed to the lower edge of the fixed section wing beam. It is used to measure the movement distance of the gear screw relative to the nut on the front and rear beams. The drive unit consists of a motor, a primary drive shaft, a secondary drive shaft, and a tertiary drive shaft. The motor and each drive shaft are mounted on a fixed section of the wing beam. After the motor starts, the four gear screws are synchronously subjected to the same driving torque through the drive shafts.

[0029] The gear screw is divided into six sections. The first section is a threaded section that fits with the nut; the second section is a cylindrical section; the third section is a circular boss, the top surface of which contacts the bottom surface of the support block; the fourth section is a cylindrical section; the fifth section is a gear, which is used to cooperate with the drive device to transmit force; the sixth section is a cylindrical section, the end of which extends into the circular recess of the stop block.

[0030] The outer contour of the nut is a quadrangular prism. One side is fixed to the upper and lower edge strips of the torsional deformation section of the wing beam, and the adjacent side is fixed to the web plate. The nut is compatible with the threaded section of the gear screw, and the thread direction of the nut at the upper and lower edge strips is opposite.

[0031] The outer contour of the support block is a quadrangular prism. One side is fixed to the upper and lower edge strips of the fixed section of the wing beam, and the adjacent side is fixed to the web plate. A circular through hole is provided on the bottom surface of the support block. The gear screw passes through the circular through hole, so that the circular boss of the gear screw contacts the bottom surface of the support block.

[0032] The outer contour of the stop block is the same as that of the support block. One side is fixed to the upper and lower edge strips of the fixed section of the wing beam, and the adjacent side is fixed to the web plate. A circular recess is provided on one of its bottom surfaces so that the smooth end of the gear screw can be inserted into the recess, which prevents the screw from axial displacement and radial oscillation.

[0033] The drive system includes a gear screw, a nut, a stop block, a support block, a rope displacement sensor, and a drive device. The bottom surface of the rope displacement sensor is attached to the web of the torsional deformation section spar, and its side is fixed to the lower edge strip of the torsional deformation section spar. The sensor's measuring head is fixed to the side of the lower edge strip of the fixed section spar. Figure 4As shown. The torsional deformation angle of the wing is measured by rope displacement sensors arranged on the front and rear spars. The distance the gear screw on the spar moves relative to the nut after deformation is obtained. The deflection angles of the front and rear spars are calculated based on the height of the spar web, and then the torsional shape of the wing is obtained by combining the chordal distance between the front and rear spars. Figure 5 As shown, when the wing is horizontal and without deflection, the measuring rope of the cable displacement sensor is stretched horizontally and taut. At this time, the sensor reading is l. i0 When the wing twists, the output value of the cable displacement sensor is l. i The displacement Δl of the gear screw i =l i -l i0 (i=1 represents the data for the front wing sparb; i=2 represents the data for the rear wing sparb). From the formula... The deflection angles of the front and rear spars can be obtained. (i=1 represents the data for the front wing sparb; i=2 represents the data for the rear wing sparb), and then the torsion angle at the span m of the wing sparb in the torsional deformation section can be calculated. Where h is the height of the beam web, m is the span of the wing beam in the torsional deformation section, f is the chordal distance between the front and rear wing beams, and the upward deflection of the wing beam is the positive direction.

[0034] Drive units are installed on the front and rear wing spars, each consisting of a motor, a primary drive shaft, a primary-secondary drive shaft, and a tertiary drive shaft. The motor and each stage of the drive shaft are mounted on a fixed section. After the motor starts, the four gear screws are synchronously subjected to the same driving torque through the drive shafts. The front and rear spars are driven in a coordinated manner. When the drive units cause the front and rear wing spars to deflect up and down around the hinge point respectively, the skin on the upper and lower surfaces of the wing restricts the distance between the front and rear spars' edge strips to remain constant, causing the wing to undergo torsional deformation.

[0035] Control process such as Figure 6 As shown: First, the relative positions of the support blocks and nuts on the front and rear wing spars are set to the initial state when the wing is without twist. At this time, the output value l of the cable displacement sensor on the front and rear wing spars is set. i0 Set as the initial reading, i.e., l 10 =l 20 =0; Set the torsion angle α at the span m of the torsional deformation section spar, and calculate the value l1 that the sensor should output after torsional deformation using the formula. ’ With l2 ’ The second step is to read the output values ​​of the sensors on the front and rear wing spars in the current state to determine the driving status of the wing drive system; if the output value of the front spars sensor is l1 = l1... ’ And the output value of the rear beam sensor is l2 = l2 ’ The wing does not need to change its flight state; if the front spar sensor output value l1 < l1 ’ Furthermore, the output value of the rear beam sensor, l2 > l2 ’The wing is positively driven (front spar deflects upward, rear spar deflects downward); if the front spar sensor output value l1 > l1 ’ And the output value of the rear beam sensor l2 < l2 ’ The wings are negatively driven (front spar deflects downwards, rear spar deflects upwards). Thirdly, if a change in drive state is needed, the control system simultaneously activates the stepper motors on both the front and rear spars. The driving force is transmitted to the gear screw via the first, second, and third stage transmission shafts, driving the front and rear spars to deflect simultaneously. The output values ​​of the cable displacement sensors on the front and rear spars are respectively equal to l1. ’ With l2 ’ At that time, the wingtip torsional deformation is completed.

[0036] The following are specific data examples of a driving and control method for changing the twist shape of an airfoil according to the present invention.

[0037] In this embodiment, a double-spar wing with airfoil NACA0012 is selected. The relative thickness of the airfoil is 12%, the chord length c = 1500 mm, and the spanwise length is 5000 mm. The front sparb is located at 25% of the airfoil chord length, and the rear sparb is located at 65% of the airfoil chord length. A hinge point is set at 3000 mm spanwise from the wing root, allowing the wing section l = 2000 mm outside the hinge point to undergo torsional deformation. The front and rear spars are I-beams with a flange thickness of 5 mm, a flange width of 84 mm, a web thickness of 4 mm, and a web height h = 120 mm.

[0038] Assume that both the gear screw and nut are made of alloy steel, the thread helix angle of the thread pair is 2.5°, and the equivalent friction angle is 7°; the outer contour of the nut is a quadrangular prism with a diameter of 20×36×24mm, where 24mm is the length in the height direction of the web, 36mm is the length in the width direction of the flange, and 20mm is the length in the direction of the gear screw. The inner diameter is 12mm, the distance from the center of the inner hole to side 1 is x=12mm, and the distance to side 2 is y=20mm. A trapezoidal thread profile with a height of 1.5mm is selected, the pitch is 2mm, and the number of thread turns is 10. The gear screw has a diameter of 12mm, a thread length of 50mm, a trapezoidal tooth profile with a height of 1.5mm, a pitch of 2mm, and 20 thread turns. A 20mm diameter boss with a thickness of 10mm is located 50mm from the thread section on the gear screw. 20mm from the boss is a standard spur gear with a pitch circle diameter of 20mm, a tooth thickness of 10mm, 20 teeth, and a module of 1. The length of the polished shaft after the gear is 20mm. The total length of the gear screw is 150mm. The stop and support blocks are both 20×36×24mm four-piece blocks. The prism has a web height of 24mm, a flange width of 36mm, and a gear screw length of 20mm. Side 1 is fixed to the flange, and side 2 is fixed to the web. On the bottom surface, with a point at a distance of x = 12mm from side 1 and y = 20mm from side 2 as the center, the stop block has a 12mm diameter and 5mm deep recess along the axis, and the support block has a 12mm diameter circular through hole along the axis. The nuts at the upper flanges of the front and rear beams are threaded in the positive direction, and the nuts at the lower flanges are threaded in the negative direction. The distance between the nut and the support block is 50mm, that is, the distance between the break points of the upper and lower flanges is 50mm. The fixed section wing beam and the torsional deformation section wing beam are hinged by a single and double lugs. The web of the fixed section wing beam has a single lug, while the web of the torsional deformation section wing beam has a double lug to ensure the transmission of shear force. Based on the allowable shear stress value, the diameter of the pin at the hinge is determined to be 12mm and the length to be 16mm. The distance between the center of the pin hole on the single lug beam and the end face of the fixed section wing beam is 25mm.

[0039] An IP54 BRT38 cable displacement sensor with dimensions of 50×50×80mm was selected. The bottom of the sensor was fixed to the web of the deformable torsion section spar; the side was fixed to the lower edge strip of the deformable torsion section spar, with the axial distance between the cable outlet on the side and the nut being 100mm; the sensor's measuring head was fixed to the side of the lower edge strip of the fixed section spar, with an axial distance of 0 from the support block. When the wing is not deflected, the length of the cable on the cable displacement sensor is 150mm, which is set as the initial reading, i.e., l. 10 =l 20 =0. From the formula Δl i =l i -l i0It can be seen that the reading of the cable displacement sensor after deflection is the displacement value of the gear screw. After the wing deflects, the direction of drive can be determined by the positive or negative reading of the sensors on the front and rear wing spars.

[0040] If the torsion angle α = 20° is to be located at a span of m = 1000 mm in the torsional deformation section, then according to the formula... The deflection angles β1 = 6.22° and β2 = -6.22° of the front and rear spars can be calculated. Furthermore, the value l1 that the cable displacement sensor on the front and rear spars should output can be calculated. ’ =13.08mm and l2 ’ = -13.08mm. Under the current flight conditions, read the values ​​from the cable displacement sensors. Assuming the sensor value on the front wing spar is l1 = 8mm and the sensor value on the rear wing spar is l2 = -8mm, then the wing is in positive drive mode. A stepper motor drives a gear screw to control the upward deflection of the front wing spar and the downward deflection of the rear wing spar. The current sensor output value on the wing spar is l1 = l1. ’ =13.08mm and the sensor output value l2 on the rear wing spar = l2 ’ When the diameter reaches -13.08 mm, the front and rear spars stop deflecting, thus completing the wing torsional deformation.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A driving and control method for changing the twist shape of an airfoil, characterized in that, A hinge point is set at a spanwise position on the front and rear spars of the wing. The section from the wing root to the hinge point is the fixed section, and the section from the hinge point to the wingtip is the torsional deformation section. The drive system includes a gear screw, nut, stop, support block, draw rope displacement sensor, and drive unit; the control method of the drive system is as follows: The first step is to set the relative positions of the support blocks and nuts on the front and rear wing spars to the initial state when the wing is without twist. At this time, the output value l of the cable displacement sensor on the front and rear wing spars is set. i0 Set as the initial reading, i.e., l 10 =l 20 =0; Set the torsion angle α at the span m of the torsional deformation section spar, and calculate the value l1 that the sensor should output after torsional deformation using the formula. ’ With l2 ’ ; The second step is to read the output values ​​of the sensors on the front and rear wing spars in the current state to determine the driving status of the drive device on the wing. If the output value of the front beam sensor is l1=l1 ’ And the output value of the rear beam sensor is l2=l2 ’ The wing does not need to change its flight state; if the front spar sensor output value l1 < l1 ’ Furthermore, the output value of the rear beam sensor, l2 > l2 ’ The wing is positively driven, meaning the front spar deflects upward and the rear spar deflects downward; if the front spar sensor output value l1 > l1 ’ And the output value of the rear beam sensor l2 < l2 ’ The wing is negatively driven, with the front spar deflecting downwards and the rear spar deflecting upwards. Thirdly, if a change in drive state is required, the stepper motors on the front and rear wing spars are simultaneously activated via the control system. The driving force is transmitted to the gear screw through the first, second, and third stage transmission shafts, driving the front and rear wing spars to deflect simultaneously. The output values ​​of the cable displacement sensors on the front and rear wing spars are respectively equal to l1 ’ With l2 ’ At that time, the wingtip torsional deformation is completed; The bottom surface of the cable displacement sensor is attached to the web of the torsional deformation section spar, and the side is fixed to the lower edge strip of the torsional deformation section spar. The measuring head of the cable displacement sensor is fixed to the side of the lower edge strip of the fixed section spar. The torsional deformation angle of the wing is measured by the cable displacement sensors arranged on the front and rear spars. The distance of movement of the gear screw on the spar relative to the nut after deformation is obtained. The deflection angle of the front and rear spars is calculated based on the height of the spar web. The torsional shape of the wing is obtained by combining the chordal distance between the front and rear spars. The web of the fixed section and the torsional deformation section are hinged by single and double lugs. The upper and lower flanges on the left and right sides of the web are connected by four gear screws. The thread direction of the upper flange gear screw is opposite to that of the lower flange gear screw. When the gear screw is driven to rotate by the motor, the gear screws of the upper and lower flanges will generate axial forces in opposite directions, forming a couple, which will cause the wing spars of the torsional deformation section to deflect around the hinge point. The front and rear wing spars of the wing deflect upward and downward around the hinge point, respectively. The skin on the upper and lower surfaces of the wing restricts the distance between the front and rear wing flanges to remain unchanged, so that the wing will undergo torsional deformation. In the aforementioned drive system: a nut is fixed to the flange of the torsional deformation section of the beam, with the bottom surface of the nut flush with the beam cross-section; a support block is fixed to the flange of the fixed section of the beam, with the bottom surface of the support block flush with the beam cross-section; a gear screw passes through the circular through hole of the support block, with the circular boss contacting the bottom surface of the support block, and the threaded section fitting the nut; a stop block is fixed to the flange of the fixed section of the beam, allowing the smooth end of the gear screw to extend into the circular recess of the stop block; wherein, the nut, the circular through hole on the support block, the gear screw, and the circular recess on the stop block are coaxial; when the gear screw rotates, the support block prevents the gear screw from axially displacing, and the stop block prevents the gear screw from axially displacing and radially swaying.

2. The driving and control method for changing the torsional shape of an airfoil according to claim 1, characterized in that, The drive unit includes a motor, a primary drive shaft, a secondary drive shaft, and a tertiary drive shaft; the motor and each drive shaft are mounted on a fixed section of the wing beam; after the motor starts, the four gear screws are synchronously subjected to the same driving torque through the drive shafts. The bottom surface of the cable displacement sensor is attached to the web of the torsional deformation section spar, and the side is fixed to the lower edge strip of the torsional deformation section spar. The measuring head is fixed to the lower edge strip of the fixed section spar and is used to measure the movement distance of the gear screw on the front and rear beams relative to the nut.

3. The driving and control method for changing the twist shape of an airfoil according to claim 2, characterized in that, Drive units are installed on the front and rear wing spars respectively. The front and rear spars are driven in coordination. When the drive units drive the front and rear wing spars to deflect up and down around the hinge point respectively, the skin on the upper and lower surfaces of the wing restricts the distance between the front and rear spars edge strips to remain unchanged, causing the wing to undergo torsional deformation.

4. The driving and control method for changing the twist shape of an airfoil according to claim 1, characterized in that, The gear screw is divided into six sections: the first section is a threaded section that fits with the nut; the second section is a cylindrical section; the third section is a circular boss, the top surface of which contacts the bottom surface of the support block; the fourth section is a cylindrical section; the fifth section is a gear, which is used to cooperate with the drive device to transmit force; and the sixth section is a cylindrical section, the end of which extends into the circular recess of the stop block.

5. The driving and control method for changing the torsional shape of an airfoil according to claim 1, characterized in that, The outer contour of the nut is a quadrangular prism, one side is fixed to the upper and lower edge strips of the torsional deformation section of the wing beam, and the adjacent side is fixed to the web plate. The nut is adapted to the threaded section of the gear screw, and the thread direction of the nut at the upper and lower edge strips is opposite.

6. The driving and control method for changing the torsional shape of an airfoil according to claim 1, characterized in that, The outer contour of the support block is a quadrangular prism, with one side fixed to the upper and lower edge strips of the fixed section of the wing beam, and the adjacent side fixed to the web plate; a circular through hole is provided on the bottom surface of the support block, and the gear screw passes through the circular through hole so that the circular boss of the gear screw contacts the bottom surface of the support block.

7. The driving and control method for changing the torsional shape of an airfoil according to claim 1, characterized in that, The outer contour of the stop block is the same as that of the support block. One side is fixed to the upper and lower edge strips of the fixed section of the wing beam, and the adjacent side is fixed to the web plate. A circular recess is provided on one bottom surface so that the smooth end of the gear screw can be inserted into the recess, which prevents the screw from axial displacement and radial oscillation.

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