AU2018420078B2

AU2018420078B2 - Fixed-wing unmanned aerial vehicle take-off and landing system and method thereof

Info

Publication number: AU2018420078B2
Application number: AU2018420078A
Authority: AU
Inventors: Ke Li; Chengyi Wang; Kun Wang; Qiuju ZHANG; Zhilei ZHENG
Original assignee: Jiangnan University
Current assignee: Jiangnan University
Priority date: 2018-11-06
Filing date: 2018-12-19
Publication date: 2021-02-11
Anticipated expiration: 2038-12-19
Also published as: CN109592060A; CN109592060B; AU2018420078A1; SG11202008018XA; WO2020093532A1

Abstract

Disclosed are a fixed-wing UAV take-off and landing system and a method thereof, including a base (1), where a front end of the base (1) is arranged with an energy storage device which includes an outer sleeve (3), a catapult (4), which slides along the outer sleeve (3), is nested within the outer sleeve (3), a rear end face of the outer sleeve (3) is arranged with a baffle plate (9), the groove frame (10) on the outer end face is provided with a locking mechanism; an end of the catapult (4) penetrates through the baffle plate (9) and snaps into the locking mechanism; a rear end face of the catapult (4) is connected to a drive control mechanism via a first rope (11) and to an arresting recovery mechanism via a third rope (16); a signal transmission and control device is arranged in the middle of the upper surface of the base (1), and an arresting net is hoisted below the front end of the base (1). The take-off and landing system is compact and reasonable in structure, convenient to operate, capable of achieving catapult takeoff and smoothly-arrested landing of fixed-wing UAVs with various sizes, and has the advantages of good invisibility, economy and adaptability. 12

Description

Fixed-Wing Unmanned Aerial Vehicle Take-Off and Landing System and

Method Thereof

TECHNICAL FIELD

[0001] The present invention relates to the technical field of an unmanned aerial vehicle

(UAV) take-off and landing apparatus, and in particular, to a fixed-wing unmanned aerial

vehicle take-off and landing system and a method thereof.

BACKGROUND

[0002] Currently, the conventional ways for fixed-wing UAV to take off are taxiing

takeoff, vertical takeoff, air delivery, ballistic catapult takeoff and hand-launched takeoff.

Compared to takeoff, UAV recovery is a phase which is more complicated and easier to have

malfunctions, and whether to land safely has become an important index for evaluating UAV

performance, and the current UAV recovery manner mainly include parachute landing

recovery, net capturing recovery, undercarriage pulley landing and aerial pickup recovery.

[0003] In the prior art, takeoff and recovery of fixed-wing UAV system are usually

mutually independent systems, moreover, one take-off apparatus or recovery system only can

satisfy one single model of fixed-wing UAV for use, the using cost is relatively high, and the

adaptability is relatively low, and it is difficult to meet the auxiliary demands for take-off and

landing of the current fixed-wing UAV.

SUMMARY

[0004] In view of the disadvantages of the prior art, the applicant provides a fixed-wing

UAV take-off and landing system with a reasonable structure and a method thereof, so as to

satisfy take-off and landing requirements of fixed-wing UAVs with different sizes and models,

improve an attendance efficiency of the UAV and reduce the space occupied by the UAV

take-off and landing apparatus.

[0005] According to a first aspect, there is provided a fixed-wing UAV take-off and

landing system, including: a base, where a front end of the base is arranged with an energy

storage device via a boss, the energy storage device includes an outer sleeve which is fixedly

arranged on an upper surface of the boss, a catapult, which slides along an outer sleeve, is

nested within the outer sleeve, a front end of the catapult is arranged with an adjustable

launcher, the adjustable launcher includes a launch rack, two sides of which are respectively

rotatablely connected to adjusting frames, inner sides of each adjusting frame are respectively

fixedly connected to UAV brackets, rear-top sides of each adjusting frame are arranged with

check frames; a rear end face of the outer sleeve is arranged with a baffle plate with a round

hole formed in the middle, a lower side of the baffle plate is connected to a groove frame

arranged at the rear end face of the boss, the groove frame is provided with a locking

mechanism, the catapult is connected to the baffle plate via a compression spring, an end of

the catapult penetrates through the round hole of the baffle plate and snaps into the locking

mechanism;

[0006] a rear end face of the catapult is connected to a drive control mechanism via a first

rope, the drive control mechanism includes a take-up reel driven by a servomotor arranged in

the middle of an upper surface of the base, a primary wiring groove is provided along the

circumference of the take-up reel for winding the first rope, a secondary wiring groove being

concentric with the primary wiring groove extends axially along an outer end surface of the

take-up reel and is wound with the second rope, and the other end of the second rope is

connected to the locking mechanism;

[0007] a rear end face of the catapult is connected to an arresting recovery mechanism via

a third rope, the arresting recovery mechanism includes tilt supports connected to both sides

of a tail end of the base, a light-weight pulley is arranged at an upper end of the tilt support

via a shaft, legs are arranged on both sides of a lower portion of the tilt support, an arresting

rope is wound on the two legs and the light-weight pulley and arranged in a triangular shape,

a rear end of the arresting rope is connected to a tension sensor, and the other end of the

tension sensor is connected to the third rope;

[0008] an arresting net is hoisted on a bottom surface of the boss; a signal transmission

and control device is arranged in the middle of the upper surface of the base, where the signal transmission and control device includes a servo drive arranged in the middle of the upper surface of the base for controlling rotation of the servomotor, an upper computer configured to calculate and transmit dynamic parameters, and a motion control card configured to receive a motion control program from the upper computer and transmit signals to the servo drive.

[0009] In one form, the locking mechanism includes two locking cams arranged oppositely, where, lower ends of the two locking cams are respectively fixed to the groove frame via a revolute pair, middle portions of the two locking cams are connected via a tension spring, upper ends of the two locking cams form a ring communicated with the round hole on the baffle plate, and an end of the catapult penetrates through the round hole of the baffle plate and snaps into the ring.

[0010] In one form, the groove frame is L-shaped and includes a vertical plane and a horizontal plane extending at the bottom, the two locking cams are arranged in the middle of the vertical plane, four corners of the vertical plane are respectively arranged with a wire guiding wheel, two wire guiding wheels are arranged on the horizontal plane at intervals, top ends of the two locking cams are respectively fixed with two joints of the second rope via eyebolts, the two joints are respectively wound around the wire guiding wheel on the vertical plane from both sides, respectively wound around the two wire guiding wheel on the horizontal plane, converged into a single rope through a latch and then wound into the secondary wiring groove.

[0011] There is provided a take-off and landing method of a fixed-wing unmanned aerial vehicle (UAV) take-off and landing system, where a process of launching the UAV including the steps of:

[0012] step one: adjusting a tilt angle of two adjusting frames relative to the launch rack, adjusting a horizontal distance between two check frames arranged on the adjusting frames, and placing the UAV about to take off on the launch rack;

[0013] step two: driving, by a servomotor, a take-up reel to rotate, so that a primary wiring groove of the take-up reel releases the first rope, after the release is completed, a secondary wiring groove continues to retract the second rope, the second rope is divided into two branches which are respectively wound around wire guiding wheel on the groove frame, the two locking cams are pulled towards the two sides, and thus releasing the catapult;

'I

[0014] step three: pushing, by a compression spring on an outer wall of the catapult to

move forward along an inner wall of the outer sleeve, and also driving the adjustable launcher

and the UAV to launch forwards together; and

[0015] a process of capturing the UAV including the steps of:

[0016] step one: hooking, by a tailhook on the back of UAV, an arresting rope wound in

wiring grooves of the leg, to drive the arresting rope to pull the tension sensor and the third

rope;

[0017] step two: pulling, by the third rope, the catapult to compress the compression

spring and absorb the kinetic energy of the UAV, where the inertia of moving upwards is

generated around the light-weight pulley at the same time of pulling the arresting rope, thus

striking the arresting net, and then completing the process of capturing.

[0018] The take-off and landing system is capable of achieving catapult takeoff and

smoothly-arrested landing of fixed-wing UAVs with various sizes, and has the advantages of

good invisibility, economy and adaptability.

[0019] By changing the tilt angle of an adjusting frame relative to a launch rack, a

horizontal distance between two check frames of a UAV can be changed, and thus fixed-wing

UAVs with various sizes can be catapulted.

[0020] The energy storage device according to the present invention not only can provide

a power supply for catapult takeoff of a fixed-wing UAV, but also absorb energy during

arresting recovery of the fixed-wing UAV, so that takeoff and recovery systems can be unified

into the same system, there is no need to independently arrange two independent facilities,

and therefore, rapid catapult takeoff and smoothly-arrested net capturing recovery of a

fixed-wing UAV can be achieved, the cost can be reduced, and the utilization rate of the

system can be improved.

[0021] Since takeoff and landing space of UAVs can be saved, the present invention is

more adaptable to auxiliary takeoff and landing requirements of fixed-wing UAVs in

environments, such as ships, mountain areas and deserts.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is a stereoscopic view according to the present invention.

[0023] FIG. 2 is a stereoscopic view (from another perspective) according to the present

invention.

[0024] FIG. 3 is an enlarged view of portion A in FIG. 1.

[0025] FIG. 4 is a schematic view with an outer sleeve removed according to the present

invention.

[0026] FIG. 5 is a schematic view in a catapult takeoff state according to the present

invention.

[0027] FIG. 6 is a schematic view in a recovery state according to the present invention.

DETAILED DESCRIPTION

[0028] As illustrated in FIG. 1 and FIG. 2, there is provided a fixed-wing unmanned aerial

vehicle (UAV) take-off and landing system according to an embodiment, including: a base 1,

a front end of which is arranged with an energy storage device via a boss 2, where the energy

storage device includes an outer sleeve 3 which is fixedly arranged on an upper surface of the

boss 2, a catapult 4, which slides along an outer sleeve 3, is nested within the outer sleeve 3, a

front end of the catapult 4 is arranged with an adjustable launcher, where the adjustable

launcher includes a launch rack 5 being fixedly arranged on an upper surface of the catapult 4

and in parallel therewith, two sides of which are respectively rotatablely connected to

adjusting frames 6, inner sides of each adjusting frame 6 are respectively fixedly connected to

UAV brackets 7, rear-top sides of each adjusting frame 6 are arranged with check frames 8; a

rear end face of the outer sleeve 3 is arranged with a baffle plate 9 with a round hole formed

in the middle, a lower side of the baffle plate 9 is connected to a groove frame 10 arranged at

the rear end face of the boss 2, the groove frame 10 is provided with a locking mechanism,

and the end of the catapult 4 penetrates through the round hole of the baffle plate 9 and snaps

into the locking mechanism;

[0029] a rear end face of the catapult 4 is connected to a drive control mechanism via a

first rope 11, the drive control mechanism includes a take-up reel driven by a servomotor 13 arranged in the middle of an upper surface of the base 1, a primary wiring groove 12 is provided along the circumference of the take-up reel for winding the first rope 11, a secondary wiring groove 14 being concentric with the primary wiring groove 12 extends axially along an outer end surface of the take-up reel and is wound with the second rope 15, and the other end of the second rope 15 is connected to the locking mechanism; a rear end face of the catapult 4 is connected to an arresting recovery mechanism via a third rope 16, the arresting recovery mechanism includes a tilt support 17 connected to a tail portion of the base 1, a light-weight pulley 33 is arranged at an upper end of the tilt support 17, legs 18 are arranged on both sides of a lower portion of the tilt support 17, an arresting rope 19 is wound on the legs 18 and the light-weight pulley 33, an end of the arresting rope 19 is connected with a tension sensor 20, and the other end of the tension sensor 20 is connected with the third rope 16; an arresting net

21 is hoisted on a bottom surface of the boss 2; a signal transmission and control device is

further arranged in the middle of the upper surface of the base 1.

[0030] Each adjusting frame 6 is of a trapezoidal structure, a round rod is arranged at the

top of the adjusting frame 6, and the two ends of the lower side of the round rod are hingedly

connected with the launch rack 5 via two inclined rods respectively, a front end surface of the

round rod is fixedly connected to a UAV bracket 7, which is of an L-shaped structure and lies

in the same horizontal plane with the round rod, the rear end of the round rod is connected

with a check frame 8 via a revolute pair, the check frame 8 is of an L-shaped structure and lies

in the same vertical plane with the round rod; and a fixing rod 23 with a chute is jointly

connected to the rear end surfaces of the check frame 8 of the two adjusting frames 6.

[0031] As illustrated in FIG. 3, the locking mechanism includes two locking cams 27

arranged oppositely, where, lower ends of the two locking cams 27 are respectively fixed to

the groove frame 10 via a revolute pair, middle portions of the two locking cams 27 are

connected via a tension spring 28, upper ends of the two locking cams 27 form a ring

communicated with the round hole on the baffle plate 9, and an end of the catapult 4

penetrates through the round hole of the baffle plate 9 and snaps into the ring.

[0032] The groove frame 10 is L-shaped and includes a vertical plane and a horizontal

plane extending at the bottom, the two locking cams 27 are arranged in the middle of the

vertical plane, four corners of the vertical plane are respectively arranged with a wire guiding wheel 29, two wire guiding wheels 29 are arranged on the horizontal plane at intervals, top ends of the two locking cams 27 are respectively fixed with two joints of the second rope 15 via eyebolts, the two joints are respectively wound around the wire guiding wheel 29 on the vertical plane from both sides, respectively wound around the two wire guiding wheel 29 on the horizontal plane, converged into a single rope through a latch and then wound into the secondary wiring groove 14.

[0033] There are two tilt supports 17, which are fixed to a tail end of the base 1 by a

screw connection, a light-weight pulley 33 is arranged at an upper end of the tilt support 17

via a shaft and a thrust bearing sleeve, there are two legs 18, which are in an inverted-V shape

and symmetrically arranged below the two tilt supports 17, upper ends of the two legs 18 are

respectively connected with the two tilt supports 17 through a hinge structure, bottom ends of

the two legs 18 are supported on the ground and provided with wiring grooves, after

extending from one end of the tension sensor 20 and winding around the light-weight pulley

33, the arresting rope 19 is split into two strands of wiring grooves winding around the

light-weight pulley 33, and an isosceles triangle-shaped wiring net is formed by the arresting

rope 19.

[0034] An arresting net 21, which is of elastic mesh surface material, is hoisted on a

bottom surface of the boss 2 via a connector 22.

[0035] The radius of the primary wiring groove 12 is larger than the radius of the

secondary wiring groove 14.

[0036] The signal transmission and control device includes a servo drive 26 arranged in

the middle of the upper surface of the base 1 for controlling rotation of the servomotor 13, an

upper computer 24 configured to calculate and transmit dynamic parameters, and a motion

control card 25 configured to receive a motion control program from the upper computer 24

and transmit signals to the servo drive 26.

[0037] As illustrated in FIG. 4, the catapult 4 is in a cylindrical shape as a whole, and a

plurality of compression springs 30 are axially arranged along the outer wall of the catapult 4,

one end of the compression spring 30 is fixed on the outer wall of the catapult 4, and the other

end of the compression spring 30 is fixed on the inner wall of the baffle plate 9, a plurality of

groove holes for receiving the compression springs 30 are axially arranged in the inner wall

'7 surface of the outer sleeve 3; an end of the catapult 4 extends to form a conical structure and matches with a round hole of the baffle plate 9.

[0038] As illustrated in FIG. 5 and FIG. 6, there is provided a take-off and landing method of a fixed-wing UAV take-off and landing system, where a process of launching the UAV 31 including the steps of:

[0039] step one: adjusting a tilt angle of two adjusting frames 6 relative to the launch rack 5, adjusting a horizontal distance between two check frames 8 on the adjusting frames 6, and placing the UAV 31 about to take off on the launch rack 5;

[0040] step two: driving, by a servomotor 13, a take-up reel to rotate, so that a primary wiring groove 12 of the take-up reel releases the first rope 11, after the release is completed, a secondary wiring groove 14 continues to retract the second rope 15, the second rope 15 is divided into two branches which are respectively wound around wire guiding wheel 29 on the groove frame 10, the two locking cams 27 are pulled towards the two sides, and thus releasing the catapult 4;

[0041] step three: pushing, by a compression spring 30 on an outer wall of the catapult 4 to move forward along an inner wall of the outer sleeve 3, and also driving the adjustable launcher and the UAV 31 to launch forwards together; and

[0042] a process of capturing the UAV 31 including the steps of:

[0043] step one: hooking, by a tailhook 32 on the back of UAV 31, an arresting rope 19 wound in wiring grooves of the leg 18, to drive the arresting rope 19 to pull the tension sensor 20 and the third rope 16;

[0044] step two: pulling, by the third rope 16, the catapult 4 to compress the spring 30 and absorb the kinetic energy of the UAV 31, where the inertia of moving upwards is generated around the light-weight pulley 33 at the same time of pulling the arresting rope 19, thus striking the arresting net 21, and then completing the process of capturing.

[0045] In this embodiment, the drive control mode of the fixed-wing UAV take-off and landing system is as follows:

[0046] Before the arresting rope 19 hooks the tailhook 32 of the UAV, the UAV 31 transmits parameters, such as a speed v, a height h and an equivalent mass M of the UAV to an upper computer 24, via a built-in wireless transmission module, and on the basis of

Q dynamic parameters of the UAV 31, the upper computer 24 calculates the kinetic energy difference AE and the potential energy difference AP during landing, and then builds a dynamic model of the fixed-wing UAV arresting system:

-$2l cos 0 - (2i|+S4)sin 0 = 3( AE - AP)2 PCos 0 MI - 21)sinO+(2i+ l)cos0 = 3(AE - AP) 1 2 sinO- g

[0047] MI

[0048] where, 1 is a displacement variation of the tension sensor after the UAV hooks the

arresting rope 19, 0 is a base angle of an isosceles triangle-shaped wiring net formed by the

arresting rope among the light-weight pulley 33 and the two legs 18, and L is a maximum

horizontal displacement of the tension sensor 20; a kinematic equation for arrested landing of

the UAV is to be solved:

i=1(t)

[0049] o=O(t)

[0050] then, according to the kinematic equation, the requiring tension T(t) of the

arresting rope and the rotational speed o(t) of the servomotor are to be solved:

[ T(t) = 3(AIE-AIP) - P [(t)] LI 2

w~)= R -1 - -/+ (OWt

[0051] ldt

[0052] where, R is the radius of the primary wiring groove of the take-up reel, and p(t) is

an angular displacement compensation function of the servomotor 13. Then, a motion control

program is generated automatically according to the rotational speed variation function of the

servomotor and downloaded to the motion control card 25, when the arresting rope 19 hooks

the tailhook 32 of the UAV, the tension sensor 20 senses the tension in the arresting rope 19,

and feedbacks to the motion control card 25, if the tension value exceeds a predefined range,

the motion control card 25 starts to execute the motion control program, and transmits pulses

to the servo drive 26 so as to drive the servomotor 13, causing the servomotor 13 to drive the

take-up reel to rotate, and pull the catapult 14 with the first rope 11 wound on the primary

wiring groove 12, thus reducing the tension value of the arresting rope 19 to a predefined

range and achieving smoothly-arrested landing of fixed-wing UAV 31.

Claims

What is claimed is: 1. A fixed-wing unmanned aerial vehicle take-off and landing system, characterized by

comprising: a base, wherein a front end of the base is arranged with an energy storage device

via a boss, the energy storage device comprises an outer sleeve which is fixedly arranged on

an upper surface of the boss, a catapult, which slides along an outer sleeve, is nested within

the outer sleeve, a front end of the catapult is arranged with an adjustable launcher, wherein

the adjustable launcher comprises a launch rack, two sides of which are respectively

rotatablely connected to adjusting frames, inner sides of each adjusting frame are respectively

fixedly connected to UAV brackets, rear-top sides of each adjusting frame are arranged with

check frames; a rear end face of the outer sleeve is arranged with a baffle plate with a round

hole formed in the middle, a lower side of the baffle plate is connected to a groove frame

arranged at the rear end face of the boss, the groove frame is provided with a locking

mechanism, the catapult is connected to the baffle plate via a compression spring, an end of

the catapult penetrates through the round hole of the baffle plate and snaps into the locking

mechanism;

a rear end face of the catapult is connected to a drive control mechanism via a first rope,

the drive control mechanism comprises a take-up reel driven by a servomotor arranged in the

middle of an upper surface of the base, a primary wiring groove is provided along the

circumference of the take-up reel for winding the first rope, a secondary wiring groove being

concentric with the primary wiring groove extends axially along an outer end surface of the

take-up reel and is wound with the second rope, and the other end of the second rope is

connected to the locking mechanism;

a rear end face of the catapult is connected to an arresting recovery mechanism via a

third rope, the arresting recovery mechanism comprises tilt supports connected to both sides

of a tail end of the base, a light-weight pulley is arranged at an upper end of the tilt support

via a shaft, legs are arranged on both sides of a lower portion of the tilt support, an arresting

rope is wound on the two legs and the light-weight pulley and arranged in a triangular shape,

1) a rear end of the arresting rope is connected to a tension sensor, and the other end of the tension sensor is connected to the third rope; an arresting net is hoisted on a bottom surface of the boss; a signal transmission and control device is arranged in the middle of the upper surface of the base, wherein the signal transmission and control device comprises a servo drive arranged in the middle of the upper surface of the base for controlling rotation of the servomotor, an upper computer configured to calculate and transmit dynamic parameters, and a motion control card configured to receive a motion control program from the upper computer and transmit signals to the servo drive.
2. The fixed-wing UAV take-off and landing system according to claim 1, characterized

in that, the locking mechanism comprises two locking cams arranged oppositely, wherein,

lower ends of the two locking cams are respectively fixed to the groove frame via a revolute

pair, middle portions of the two locking cams are connected via a tension spring, upper ends

of the two locking cams form a ring communicated with the round hole on the baffle plate,

and an end of the catapult penetrates through the round hole of the baffle plate and snaps into

the ring.
3. The fixed-wing UAV take-off and landing system according to claim 2, characterized

in that, the groove frame is L-shaped and comprises a vertical plane and a horizontal plane

extending at the bottom, the two locking cams are arranged in the middle of the vertical plane,

four corners of the vertical plane are respectively arranged with a wire guiding wheel, two

wire guiding wheels are arranged on the horizontal plane at intervals, top ends of the two

locking cams are respectively fixed with two joints of the second rope via eyebolts, the two

joints are respectively wound around the wire guiding wheel on the vertical plane from both

sides, respectively wound around the two wire guiding wheel on the horizontal plane,

converged into a single rope through a latch and then wound into the secondary wiring

groove.
4. A take-off and landing method of a fixed-wing UAV take-off and landing system

according to claim 1, characterized in that, a process of launching a UAV comprising the steps

of:

step one: adjusting a tilt angle of two adjusting frames relative to the launch rack,

adjusting a horizontal distance between two check frames arranged on the adjusting frames, and placing the UAV about to take off on the launch rack; step two: driving, by a servomotor, a take-up reel to rotate, so that a primary wiring groove of the take-up reel releases the first rope, after the release is completed, a secondary wiring groove continues to retract the second rope, the second rope is divided into two branches which are respectively wound around wire guiding wheel on the groove frame, the two locking cams are pulled towards the two sides, and thus releasing the catapult; step three: pushing, by the compression spring on an outer wall of the catapult to move forward along an inner wall of the outer sleeve, and also driving the adjustable launcher and the UAV to launch forwards together; and a process of capturing the UAV comprising the steps of: step one: hooking, by a tailhook on the back of UAV, an arresting rope wound in wiring grooves of the leg, to drive the arresting rope to pull the tension sensor and the third rope; step two: pulling, by the third rope, the catapult to compress the compression spring and absorb the kinetic energy of the UAV, wherein the inertia of moving upwards is generated around the light-weight pulley at the same time of pulling the arresting rope, thus striking the arresting net, and then completing the process of capturing.

1)