CN-121990159-A - Tailstock type vertical take-off and landing aircraft with foldable outer-section wings and design method thereof

CN121990159ACN 121990159 ACN121990159 ACN 121990159ACN-121990159-A

Abstract

The invention discloses a tailstock type vertical take-off and landing aircraft with a foldable outer-section wing and a design method thereof, wherein the folding and unfolding of the outer-section wing can be realized by matching a folding and unfolding driving mechanism with a four-bar mechanism, and the weight brought by a folding device is reduced on the premise of ensuring driving force and maintainability; when the wings are fully folded, the aircraft is in a four-rotor state, and when the wings are fully unfolded, the aircraft is in a fixed wing state, the folding and unfolding of the wings are compatible with the transformation of the flying form, and the folding of the outer-section wings is realized on the premise of ensuring the reasonable gravity centers and inertia of the fixed wing state and the rotor wing states under various folding and unfolding angles through reasonable configuration of the gravity centers of all shafts of the vertical take-off and landing aircraft, so that the space cost of the aircraft is reduced.

Inventors

WANG ZILONG
LIU YANBIN
ZHAO ZENGZHEN
Cheng Peiran

Assignees

南京航空航天大学

Dates

Publication Date: 20260508
Application Date: 20260128

Claims (7)

1. A tailstock type vertical take-off and landing aircraft with foldable outer-section wings is characterized by comprising a fuselage, a vertical tail and wings, wherein the wings are divided into inner-section wings and outer-section wings, the inner sides of the inner-section wings are directly connected with the fuselage, folding and unfolding driving mechanisms are arranged on the outer sides of the inner-section wings and used for driving the outer-section wings to fold and unfold, the folding and unfolding driving mechanisms are formed by driving steering engines, steering engine rocker arms, carbon pull rods and partial girders of the inner-section outer-section wings and form a four-bar mechanism, the vertical tail is arranged at the rear part of the fuselage, is used as a landing bracket during vertical take-off and landing, and is used as a vertical tail during flat flight.
2. The tail stock type vertical take-off and landing aircraft with the foldable outer-section wing according to claim 1, wherein the folding and unfolding driving mechanism is driven by a driving steering engine, the driving steering engine drives a steering engine rocker arm and a carbon pull rod along with the steering engine rocker arm, and finally, a four-bar mechanism with an inner Duan Jiyi main beam and an outer-section wing main beam is driven, so that folding and unfolding movement of the outer-section wing is controlled.
3. A method of designing a tailstock type vertical takeoff and landing aircraft having a foldable outer section wing as defined in claim 1, comprising the steps of: In the fully unfolded state, the Z-axis coordinate value of the outer motor is the same as the Z-axis of the central coordinate of the airframe, and in other folded angle states, the Z-axis coordinate value of the outer motor is always smaller than the Z-axis of the central coordinate of the airframe; Estimating the Z-axis center of gravity position of the whole machine under different folding and unfolding angles according to a geometric relation by using known and estimated geometric data and key equipment weight, setting a constraint function and a cost function by taking the middle point of an outer section wing as a reference point, and searching an inner section wing dihedral angle and an outer section wing dihedral angle which enable the cost function to be minimum and meet the constraint function; Through reasonable selection of the lower dihedral angle of the inner-section wing, the Z-axis coordinate of the gravity center of the outer-section wing is ensured not to deviate from the Z-axis coordinate of an intersection point generated by a diagonal rotor line in the folding process, the vertical take-off of the tailstock is realized on the premise of installing four motors with the same specification and the same output force, the outer-section wing is unfolded in a rotor mode, the low-head acceleration is carried out to turn flat flight after the unfolding is completed, in the landing process, the head is raised first to climb up for deceleration, the unfolded rotor mode is used for lowering the height after the gesture conversion is completed, and the outer-section wing is folded and landed in the tailstock in the state when the height is lower.
4. A method of designing a tailstock-type vertical takeoff and landing aircraft with a foldable outer section wing as defined in claim 3, wherein the following constraint functions are set: in the formula, Is the projection extension of a single-section wing, Is the position of the center of gravity of the battery is set in the Z-axis offset of (c), Is the Z-axis offset of the gravity center position of the steering engine, Is the maximum mass of a single-side single-section wing, For the mass of the fuselage with the equipment, The steering engine and the auxiliary pull rod are driven by single-side folding and unfolding, Is the mass of the single-side battery, The method comprises the steps of calculating the real length of a single-section wing, calculating the maximum weight limit obtained by overall design of the single-section wing, calculating the larger the dihedral angle, the larger the length of the single-section wing and the larger the weight, and then calculating the Z-axis position of the combined gravity center of an important component relative to the midpoint of the outer-section wing, wherein the closer the upper gravity center of the Z-axis is to the midpoint of the outer-section wing, the better the distance between the upper gravity center of the Z-axis and the midpoint of the outer-section wing is.
5. A method of designing a tailstock-type vertical takeoff and landing aircraft with foldable outer section wings according to claim 3, characterized in that by geometrical relations, the desired dihedral should be around 30 ° and the smaller the better, the folded angle When the angles are 0 degree, 15 degree, 30 degree, 45 degree and 60 degree, the angles are used as test points for different lower dihedral angles of the inner section wing Performing traversal calculation with the step length of 0.1 DEG in the range of 20 DEG to 30 DEG to obtain cost function values under different dihedral angles.
6. The method of designing a tailstock type vertical takeoff and landing aircraft with a foldable outer section wing according to claim 5, wherein the cost function is as follows: Wherein the method comprises the steps of Representing the weight of the single-section wing, Representing the weight of a single-section wing, For the weights arranged from small to large state for the selected fold angle, The weight of the whole machine is gradually reduced from 0 degree to 60 degrees when the whole machine is set to be lighter and better when the whole machine is closer to the midpoint of the outer wing under different folding angles, 。
7. The method of designing a tailstock type vertical takeoff and landing aircraft with a foldable outer wing according to claim 6, wherein the inner wing dihedral and the outer wing dihedral are optimal at 26.6 °.

Description

Tailstock type vertical take-off and landing aircraft with foldable outer-section wings and design method thereof Technical Field The invention relates to the technical field of foldable wing vertical take-off and landing aircrafts, in particular to a tailstock type vertical take-off and landing aircrafts with foldable outer sections of wings and a design method thereof. Background Mechanical folding and unfolding technology has been developed remarkably in various fields, particularly in the aviation and aerospace fields, and efficient folding and unfolding are achieved through a multi-link hinge system and hydraulic driving and lightweight materials. Typical applications include a deformed tip of XB-70, a collapsible tip of the Boeing 777X, which uses hinges and hydraulic actuators, the deformed tip of XB-70 being folded down to increase lift by shock waves at high speeds, the tip of Boeing 777X being deployed to increase cruise efficiency in terms of wingspan. The prior art still faces the challenges that the driving device is more, the mass is heavier, the folding and unfolding influences the gravity center position to influence the control of the vertical take-off and landing aircraft when hovering, or the control effect of the fixed wing in the cruising state is influenced because the wing shape has a mounting angle or a dihedral angle due to folding and unfolding. Disclosure of Invention The invention aims to provide a tailstock type vertical take-off and landing aircraft with foldable outer-section wings and a design method thereof, which can realize folding of the outer-section wings on the premise of ensuring reasonable gravity center and inertia of a fixed wing state and a rotor wing state under each folding angle, and reduce the space cost of the aircraft. The tail seat type vertical take-off and landing aircraft with the foldable outer section wings comprises a fuselage, a vertical tail and wings, wherein the wings are divided into inner section wings and outer section wings, the inner sides of the inner section wings are directly connected with the fuselage, folding and unfolding driving mechanisms are arranged on the outer sides of the inner section wings and used for driving the outer section wings to fold and unfold, the folding and unfolding driving mechanisms are formed by driving steering engines, steering engine rocker arms, carbon pull rods and partial main beams of the inner section outer section wings and form a four-bar mechanism, the vertical tail is arranged at the rear part of the fuselage and serves as a landing bracket during vertical take-off and landing, and serves as a vertical tail wing during flat flight. Further, the folding and unfolding driving mechanism is driven by the driving steering engine, the driving steering engine drives the steering engine rocker arm and drives the carbon pull rod along with the steering engine rocker arm, and finally, the four-bar mechanism of the inner Duan Jiyi main beam and the outer wing main beam is driven, so that folding and unfolding movement of the outer wing is controlled. Correspondingly, the design method of the tailstock type vertical take-off and landing aircraft with the foldable outer section wings comprises the following steps: In the fully unfolded state, the Z-axis coordinate value of the outer motor is the same as the Z-axis of the central coordinate of the airframe, and in other folded angle states, the Z-axis coordinate value of the outer motor is always smaller than the Z-axis of the central coordinate of the airframe; Estimating the Z-axis center of gravity position of the whole machine under different folding and unfolding angles according to a geometric relation by using known and estimated geometric data and key equipment weight, setting a constraint function and a cost function by taking the middle point of an outer section wing as a reference point, and searching an inner section wing dihedral angle and an outer section wing dihedral angle which enable the cost function to be minimum and meet the constraint function; Through reasonable selection of the lower dihedral angle of the inner-section wing, the Z-axis coordinate of the gravity center of the outer-section wing is ensured not to deviate from the Z-axis coordinate of an intersection point generated by a diagonal rotor line in the folding process, the vertical take-off of the tailstock is realized on the premise of installing four motors with the same specification and the same output force, the outer-section wing is unfolded in a rotor mode, the low-head acceleration is carried out to turn flat flight after the unfolding is completed, in the landing process, the head is raised first to climb up for deceleration, the unfolded rotor mode is used for lowering the height after the gesture conversion is completed, and the outer-section wing is folded and landed in the tailstock in the state when the height is lower. Further, the following constraint functions are