CN204342167U - The cable actinobacillus device of coaxial double-rotary wing depopulated helicopter - Google Patents
The cable actinobacillus device of coaxial double-rotary wing depopulated helicopter Download PDFInfo
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- CN204342167U CN204342167U CN201420722028.1U CN201420722028U CN204342167U CN 204342167 U CN204342167 U CN 204342167U CN 201420722028 U CN201420722028 U CN 201420722028U CN 204342167 U CN204342167 U CN 204342167U
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Abstract
A kind of cable paying-off device, it comprises framework, the framework that this framework is rectangle by two cross-sectional planes integrally connects and composes, the length of the framework of two rectangles and width are all different, an i.e. large rectangle framework and a little rectangular frame, a common edge is comprised between this little rectangular frame and large rectangle framework, setting-in wire coil for optical cable (1) in large rectangle framework, in large rectangle framework, motor (2) is equipped with in the front portion of described wire coil for optical cable (1), the output shaft of this motor (2) is connected with the wire coil shaft of described wire coil for optical cable (1), in described little rectangular frame by before backward successively installation tension take turns (3) and cable guide (4), cable motion sensor (5) is equipped with in the front of this cable guide (4), emergent cutter (6) is equipped with in the front of this cable motion sensor (5).When there is the out of control or cable of tension force and the unforeseen circumstancess such as winding occur body in emergent cutter (6), instantaneous by cable cutting by priming system, in order to avoid cause the major accidents such as air crash.
Description
Technical field
The utility model relates to a kind of cable actinobacillus device, and particularly a kind of cable actinobacillus device for coaxial double-rotary wing depopulated helicopter, belongs to technical field of aerospace.
Background technology
Landing is convenient, spot hover, mobility strong because it possesses for depopulated helicopter, therefore fights of many uses, has considerable operational potential and development prospect.Carry out depopulated helicopter development country relatively early abroad and have the U.S., Britain, Canada, Germany etc.Wherein the U.S. just begins one's study depopulated helicopter the fifties in last century, and the antisubmarine RC Goblin of the QH-50A sixties makes a successful trial flight, and in Vietnam War, United States Army just uses QH-50D depopulated helicopter to perform the tasks such as scouting, battlefield surveillance, artilleryman's target observation.Because unmanned helicopter flight control technology exists many difficult points, so depopulated helicopter is for fixed-wing unmanned plane, the development of technology and application is always comparatively slow.
In depopulated helicopter, coaxial double-rotary wing is a kind of important helicopter distribution form, coaxial double-rotary wing depopulated helicopter and conventional unmanned plane layout have very big difference, coaxial double-rotary wing depopulated helicopter has the two width rotors up and down around same axis positive and negative rotation, because two width rotor wing rotation directions are contrary, so its moment of torsion produced is cancelled out each other when course is constant, thus eliminate tail-rotor; Realized the directional control of depopulated helicopter by the differential operation of the total distance of upper and lower rotor, two width rotors are lifting surface and in length and breadth to the controlsurface with course in the flight course of helicopter simultaneously.Coaxial double-rotary wing depopulated helicopter, due to the distribution form of uniqueness, is very applicable to laying fast of optical cable one class flexible cable.Cable releasing mechanism and unmanned plane body are carried out integrated, utilizes depopulated helicopter rapid flight and vertical takeoff and landing ability, realize a maneuverability, the quick laying system of adaptable unmanned plane cable.
But want engineering to realize this system, there is following difficulty:
1) depopulated helicopter is complicated non-linear, a multi-input multi-output system
From system perspective analysis, depopulated helicopter non-linear be mainly present in the non-linear of math modeling and actuating unit non-linear on.Because the nonlinear effect of rotor power characteristic is serious, the property difference of depopulated helicopter not only when different flight state is comparatively large, even and if in same state of flight, when applying manoeuvre amount, also can inspire strong nonlinearity response.Meanwhile, because the intrinsic coupling between depopulated helicopter passage is serious, the non-linear flight response not only affecting this passage of the actuating unit of a passage, also can have influence on the response of other passages strongly.
2) uncertainty of control object
The significant challenge that depopulated helicopter independent flight control system designer faces is the uncertainty of how processing controls object, namely depopulated helicopter dynamics described by mathematical modeling and real system inconsistent time, how still can aircraft be controlled accurately and effectively.From the angle analysis of control system theory, depopulated helicopter independent flight control system must have very strong robustness, and concrete control algorithm and controling parameters should be weak relevant to dynamicmodel, for the structure of model or Parameter Perturbation insensitive.
For the depopulated helicopter of fiber cable laying, except above-mentioned difficulties, also must consider the specific question of flexible cable in laid processes.
Primary need is to the stress of cable, and namely suffered tension force accurately detects and estimates, and controls the payingoff speed of reel, and the tension force of guarantee suffered by optical cable, below specified value, makes cable configuration from mechanical damage.
Secondary need controls the payingoff speed of optical cable, guarantees that optical cable is applied to the external force of coaxial double-rotary wing unmanned plane in unwrapping wire process constant.
3rd needs to optimize Flight Control Algorithm under the disturbance of flexible cable tension force, improves the flight quality of aircraft platforms, makes aircraft platforms have good handling stability.
Utility model content
For above object, first aspect of the present utility model provides a kind of cable actinobacillus device of coaxial double-rotary wing depopulated helicopter, it comprises framework, the framework that this framework is rectangle by two cross-sectional planes integrally connects and composes, the length of the framework of two rectangles and width are all different, an i.e. large rectangle framework and a little rectangular frame, a common edge is comprised between this little rectangular frame and large rectangle framework, setting-in wire coil for optical cable in large rectangle framework, in large rectangle framework, motor is equipped with in the front portion of described wire coil for optical cable, the output shaft of this motor is connected with the wire coil shaft of described wire coil for optical cable, in described little rectangular frame by before backward successively installation tension take turns and cable guide, cable motion sensor is equipped with in the front of this cable guide, emergent cutter is equipped with in the front of this cable motion sensor, cable on described wire coil for optical cable is connected to straining pulley, also tension pick-up is housed between straining pulley and little rectangular frame, to measure the tension force of cable between wire coil for optical cable and straining pulley, namely the equipment in large rectangle framework forms payingoff mechanism, equipment in little rectangular frame forms tension control mechanism.
Preferably, described motor is DC machine.
The mode of operation of the cable paying-off device that the utility model first aspect provides is: by control command incoming task control setup, this control setup controls payingoff mechanism and releases cable, tension pick-up is by parameter feedbacks such as the height of cable, speed, courses to air route maker, and the speed parameter of this air route maker and tension control mechanism controls the flight parameter of depopulated helicopter by inner ring control system; In this process, cable is outwards discharged by straining pulley, the direction of cable guide to cable play the guiding role, cable motion sensor measure cable release rate and as the input parameter of inner ring control system, the effect of emergent cutter is when there is the out of control or unforeseen circumstances such as cable and body generation winding of tension force, instantaneous by cable cutting by priming system, in order to avoid cause the major accidents such as air crash.
The utility model second aspect provides a kind of coaxial double-rotary wing unmanned helicopter flight control algorithm, and it comprises:
(1) dynamics model analysis of coaxial double-rotary wing depopulated helicopter and flexible cable
Consider the control structure of flight control system system, adopt the model that two independent, its core drive model is by the kinetics equation of the attitude and speed characteristic of reacting separately helicopter.It is one 2 input, 6 systems exported that control structure determines this model, and its state space equation is expressed and seen formula (3.1):
，
（3.1）
In formula (3.1),
,
,
Wherein: A condition matrix B input matrix C output matrix
---horizontal rotor angle of flap;
---longitudinal rotor angle of flap; P---course angle speed;
Q---pitch rate;
---roll angle;
---pitch angle;
---forward speed;
---side velocity;
---longitudinal cyclic pitch;
---horizontal cyclic pitch;
Guarantee control system design and accuracy of simulation basis on, system linearization model is:
（3.2）
Carry out parameter identification test: first time test does not add mooring cable, second load flexible cable, and aircraft forward flight speed is 5m/s; Third time test loads flexible cable, and aircraft forward flight speed is 12m/s.The result of this cubic parametric identification test is analysed and compared, finds in parameter model,
with vehicle flight speeds positive correlation,
with percentage speed variation, the rate of change positive correlation particularly with speed in z-axis.By the test of cubic parametric identification, obtain flexible cable to the impact of unmanned aerial vehicle platform solid pattern.
Experimental result fully shows, the dynamic characteristic in the flight course of the unmanned plane of flexible cable is very complicated, and the model given by us obviously can not describe its whole feature completely, particularly when the attitude of unmanned helicopter platform, course change.The dynamics of flexible cable is easily subject to the impact of DCB Specimen purling, and this effect is quite remarkable under specific state.Because these disturbances are difficult to provide accurate description, this just requires that we will focus on Focus Control object model when departing from when design of control law, the validity of control algorithm.
(2) flight control system functional structure
Unmanned plane will be executed the task when unmanned the intervention, and automatic flight control system is one of indispensable link.Because structure is simple, parameter tuning is quick, and key is not high to the accuracy requirement of depopulated helicopter kinetic model, so be that the classical feedback of representative was once widely used in helicopter flight control system with PID.But will promote the flight envelope of depopulated helicopter further, complete more complicated task, this simple control policy is incompetent.Therefore, we must the more advanced control algorithm of demand, on the basis meeting controlling functions, promotes the flight quality of depopulated helicopter.
The utility model proposes the control method of the kinetic model that is determined for formula (3.2).Based on the state variable of this model, adopt the coaxial double-rotary wing unmanned helicopter flight control system of tri-layer two loop structure, wherein inner ring is used for calm and Eulerian angles, angular rate, and the dynamics that rotor angle of flap is relevant up and down; And the yaw control channel of helicopter is set up by the differentiating control of upper and lower two rotors.
The position of the unmanned aerial vehicle platform under outer shroud control NED system of axes, speed.Complete tension force to control to be cross-linked with the logic of flight control system simultaneously.
Prove through test, this structure is extremely successful for the control of so complicated synthesis, effectively can suppress the disturbance that the aerial compound movement pattern of flexible cable is brought.
More multioperation is all known for those of ordinary skills, repeats no more.
The technical scheme of cable paying-off device provided by the utility model and coaxial double-rotary wing unmanned helicopter flight control algorithm comprises the combination in any of each part mentioned above, and simple change or the combination of each part mentioned above assembly are still protection domain of the present utility model.
The control that coaxial double-rotary wing unmanned helicopter flight control algorithm provided by the utility model is the coaxial double-rotary wing depopulated helicopter laid for flexible cable provides theoretical method basis and engineering technology to instruct.
Accompanying drawing explanation
Fig. 1 is the stressed simplified model schematic diagram of the entirety that pulls flexible cable according to coaxial double-rotary wing depopulated helicopter of the present utility model.
Fig. 2 is that cable embodiment illustrated in fig. 1 lays fast with coaxial double-rotary wing unmanned helicopter flight control system outer ring structure.
Fig. 3 is that cable embodiment illustrated in fig. 1 lays fast with ring structure in coaxial double-rotary wing unmanned helicopter flight control system.
Fig. 4 is payingoff mechanism schematic diagram embodiment illustrated in fig. 1.
Fig. 5 is inner ring controller architecture schematic diagram embodiment illustrated in fig. 1.
Fig. 6 is inertial delay switching construction embodiment illustrated in fig. 1.
Fig. 7 is the cable strain diagram of curves of a preferred embodiment of coaxial double-rotary wing unmanned helicopter flight control algorithm described in the utility model.
Fig. 8 is roll angle control effects figure embodiment illustrated in fig. 7.
Fig. 9 is pitch angle control effects figure embodiment illustrated in fig. 7.
Figure 10 is course angle control effects figure embodiment illustrated in fig. 7.
Figure 11 is TRAJECTORY CONTROL design sketch embodiment illustrated in fig. 7.
The implication of the figure notation in Fig. 1-Figure 11 is:
1 wire coil for optical cable 2 DC machine 3 straining pulley 4 cable guide
5 cable motion sensors 6 are met an urgent need cutter 7 tension pick-up.
Detailed description of the invention
In order to understand the utility model better, describe the preferred embodiment of cable paying-off device according to coaxial double-rotary wing depopulated helicopter of the present utility model and coaxial double-rotary wing unmanned helicopter flight control algorithm respectively in detail below in conjunction with accompanying drawing.
embodiment 1.1:a kind of cable paying-off device, it comprises framework, the framework that this framework is rectangle by two cross-sectional planes integrally connects and composes, the length of the framework of two rectangles and width are all different, an i.e. large rectangle framework and a little rectangular frame, a common edge is comprised between this little rectangular frame and large rectangle framework, setting-in wire coil for optical cable 1 in large rectangle framework, in large rectangle framework, DC machine 2 is equipped with in the front portion of described wire coil for optical cable 1, the output shaft of this DC machine 2 is connected with the wire coil shaft of described wire coil for optical cable 1, in described little rectangular frame by before backward successively installation tension take turns 3 and cable guide 4, cable motion sensor 5 is equipped with in the front of this cable guide 4, emergent cutter 6 is equipped with in the front of this cable motion sensor 5, cable on described wire coil for optical cable 1 is connected to straining pulley 3, between straining pulley 3 and little rectangular frame, tension pick-up 7 is also housed, to measure the tension force of cable between wire coil for optical cable 1 and straining pulley 3, namely the equipment in large rectangle framework forms payingoff mechanism, equipment in little rectangular frame forms tension control mechanism.
The mode of operation of the cable paying-off device that the present embodiment provides is: by control command incoming task control setup, this control setup controls payingoff mechanism and releases cable, tension pick-up is by parameter feedbacks such as the height of cable, speed, courses to air route maker, and the speed parameter of this air route maker and tension control mechanism controls the flight parameter of depopulated helicopter by inner ring control system; In this process, cable is outwards discharged by straining pulley 3, the direction of cable guide 4 pairs of cables play the guiding role, cable motion sensor 5 measure cable release rate and as the input parameter of inner ring control system, the effect of emergent cutter 6 is when there is the out of control or unforeseen circumstances such as cable and body generation winding of tension force, instantaneous by cable cutting by priming system, in order to avoid cause the major accidents such as air crash.
embodiment 1.2:coaxial double-rotary wing unmanned helicopter flight control algorithm, concrete steps are divided into following three steps: dynamicmodel linearization; H ∞ design of control law and the design of controller switch logic.
4.1 model linearization
By the analysis of upper joint, we think for the equation of state of this fabricate block of coaxial double-rotary wing towing flexible cable, in its state matrix
with
be actually the amount changed with unmanned plane during flying Parameters variation, we are when Control System Design, must choose corresponding operation point, and carry out system linearization in this operation point, thus launch the design of control.According to the mode of operation of system reality, we select two operation points in this patent, first are floating state, second are greater than 10m/s for speed.
Described in model structure as above saves:
,
.Based on this inearized model, complete inner ring control design case by H ∞ control algorithm.
Known, flexible cable velocity-tension relationship affect depopulated helicopter stressed, and then affect the attitude dynamics feature of helicopter, therefore, is considered as the disturbance in inner ring control technology loop by the relation of flexible cable speed and tension force.
So this inearized model changes into
（4.1）
Wherein matrix E is interference matrix, during linearization, the value of E is under different operating point, obtained by the disturbance introducing flexible cable in longitudinal direction, interconnection, and this disturbance is obtained through algorithm for estimating by the responsive angle of cable strain, cable motion detection sensor, angle rate signal.Prove that this disturbance only affects angular rate q, p through test.
Measurement output is
(4.2)
The basic demand of inner ring is the control and stability ensureing attitude when flexible cable disturbs, and therefore controlled output variable is chosen as:
（4.3）
（4.4）
In above formula
with
for variable bound matrix, its element is weight coefficient.
4.2 H ∞ design of control laws
Basic requirement be minimize cable disturbance on the impact of system, namely minimize closed loop system transfer function matrix from interference w to the H ∞ norm of controlled input Hin or Hout.
The control structure of interior ring controller as shown in Figure 5.
Obtain the expression formula of interior ring controller, first determine
with
for variable bound entry of a matrix element, i.e. weight coefficient.Then the H ∞ performance index from exogenous disturbances w to controlled output Hin optimum is calculated
.
For arbitrarily
>
, H ∞'s
suboptimal control rule is:
（4.5）
Wherein r is reference input, and r=[Φ r, θ r] is produced by outer shroud control law.
for feedback of status gain.
P is the calm solution of positive semidefinite of H ∞ Algebraic Riccati equations.This Riccati equation is defined as follows:
（4.6）
G is with reference to forward direction matrix,
(4.7).
The switch logic of 4.3 controllers
When unmanned plane hover and before fly two different operating points fly time, need the switching carrying out controller.The switch logic design of controller will ensure seamlessly transitting without step of handoff procedure exactly, wants keeping system to the tracking performance of reference input simultaneously.We adopt inertial delay changing method, and the method structure is simple, effectively can avoid the step effect in handoff procedure simultaneously.
As shown in Figure 6, wherein ua is the output of control Ka to switch logic, and ub is the output of control Kb, uses inertial delay function when switching
（4.8）
So when being switched to ub by ua, the output after switching
（4.9）
This is a combined value switching the decaying exponential function of difference, therefore can ensure the smooth of handoff procedure.
The result that a concrete coaxial double-rotary wing unmanned helicopter flight control algorithm realizes is as follows:
Forward flight=the 5m/s of coaxial double-rotary wing unmanned plane, wind speed average is at 7m/s, and the cable strain utilizing above-mentioned control algorithm to obtain, attitude angle, angular rate control result as shown in Fig. 7-Figure 11.
Can find out, the peak value of cable strain is controlled within 0.5N, it is limited within the scope of an acceptable to the disturbance of attitude of flight vehicle and flight path, the control effects of aircraft roll angle and pitch angle further proves this point, the pitch angle that practical flight measures, roll angle and given reference value conformability are very high, through measurement and statistics, the control accuracy of attitude angle at 2 °, course angle control accuracy 3 °.The flight path control effects of aircraft as shown in figure 11.
Described in the present embodiment, coaxial double-rotary wing unmanned helicopter flight control algorithm innovative point is compared with prior art:
1) design one effectively can measure optical cable cable attitude, tension force in unwrapping wire process, and complete constant tensile control active release line mechanism
2) devise a two circuit flight control system structure of tri-layer, cable strain control to carry out with the speed of aircraft, gesture stability to unify to consider by this structure, complex optimum.
3) design and Implement the Flight Control Algorithm based on H ∞ robust control technique, effectively can suppress flexible cable disturbance in unwrapping wire process.
Claims (5)
1. a cable paying-off device, it comprises framework, the framework that this framework is rectangle by two cross-sectional planes integrally connects and composes, the length of the framework of two rectangles and width are all different, an i.e. large rectangle framework and a little rectangular frame, a common edge is comprised between this little rectangular frame and large rectangle framework, setting-in wire coil for optical cable (1) in large rectangle framework, in large rectangle framework, motor (2) is equipped with in the front portion of described wire coil for optical cable (1), the output shaft of this motor (2) is connected with the wire coil shaft of described wire coil for optical cable (1), in described little rectangular frame by before backward successively installation tension take turns (3) and cable guide (4), it is characterized in that: cable motion sensor (5) is equipped with in the front of cable guide (4), emergent cutter (6) is equipped with in the front of this cable motion sensor (5).
2. cable paying-off device as claimed in claim 1, is characterized in that: the cable on described wire coil for optical cable (1) is connected to straining pulley (3).
3. cable paying-off device as claimed in claim 2, it is characterized in that: between straining pulley (3) and little rectangular frame, also tension pick-up is housed, to measure the tension force of cable between wire coil for optical cable (1) and straining pulley (3), namely the equipment in large rectangle framework forms payingoff mechanism, and the equipment in little rectangular frame forms tension control mechanism.
4. the cable paying-off device according to any one of claim 1-3, is characterized in that: motor (2) is DC machine.
5. the cable paying-off device according to any one of claim 1-3, is characterized in that: the peak value of cable strain is controlled within 0.5N.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109622820A (en) * | 2018-12-27 | 2019-04-16 | 中国船舶重工集团公司第七0研究所 | A kind of underwater compound towrope emergency cutting mechanism |
| CN111039101A (en) * | 2018-10-11 | 2020-04-21 | 古德里奇公司 | Cable deflection detection with contact |
-
2014
- 2014-11-26 CN CN201420722028.1U patent/CN204342167U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111039101A (en) * | 2018-10-11 | 2020-04-21 | 古德里奇公司 | Cable deflection detection with contact |
| CN109622820A (en) * | 2018-12-27 | 2019-04-16 | 中国船舶重工集团公司第七0研究所 | A kind of underwater compound towrope emergency cutting mechanism |
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