CN107545108A - Enhancing measures are pulled to mass ratio in the towing region that fragment removes task - Google Patents
Enhancing measures are pulled to mass ratio in the towing region that fragment removes task Download PDFInfo
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Abstract
Enhancing measures are pulled in the towing region that task is removed the present invention relates to fragment to mass ratio, belong to space junk and remove field.This method core concept is：Relation between chip Natural Attenuation time and its initial mass is connected with the final desired sail surface to leave the right or normal track needed for the time, and removes standard based on current fragment, and the towing sail designed by this method has been considered for driving final equation；And this method typically has no effect on sail type, the design parameter that it can limit any towing sail is circulated with further optimization design；The similar tasks international standard of main space mechanism of the world is used, so the task of any country's definition can be calculated in this way.
Description
Technical field
The present invention is that the passive approach of task is removed for fragment, especially, relevant with pneumatic towing strengthening system, is related to
Enhancing measures are pulled in Ahmadloo inequality, the towing region that task is removed more specifically to fragment to mass ratio,
Belong to space junk and remove field.
Background technology
The useful life for being transmitted into all spacecrafts of space is limited.After their life cycle, spacecraft and defend
Star is not just used, and they are accumulated in space, adds the quantity of fragment.Unless being removed or burning in an atmosphere, otherwise navigate
Its device and satellite are remained on track, and with the increase of number of tiles, the collision between them, which is possibly realized, to be caused to produce
More chips, this phenomenon turn into normality.
Nowadays, there is several methods that can be left the right or normal track with the spacecraft of end of life.All technologies are intended to perigee height
Degree is reduced to aerodynamic force and becomes large enough to cause finally again to enter the orbit.Now, it is applied to the aerodynamics of spacecraft or satellite
Heating and pressure will increase, and spacecraft or satellite will be damaged by large area in an atmosphere.
Today, the leading strategy that leaves the right or normal track, which is directed to use with small rocket motor, electronic tether or pneumatic towing enhancing, to be come by force
System reenters, so as to reach the purpose for eliminating target debris.
Small rocket motor can be used for pushing satellite to the earth at a particular angle and speed, during ensuring to enter the orbit again
Damage.The speed that rocket engine may be used to its decline of reduction satellite and burn in an atmosphere.This technology development utilization
The missilery of business level has been reached.The major advantage of the rocket is shot by accurate angle to control unloading process.
However, rocketry has extremely expensive, quality very heavy and the defects of technical sophistication, including keep rocket fuel at it
The pressure of more than 10 years is kept before end of life.
Electronic tether is a conductive contact, leaves the right or normal track between spacecraft and the end of a certain distance deployment and prolongs at one
Stretch, it is possible to extend downwardly several kilometers of distances.Therefore, tether technology is related to from the deployment of passing of satelline magnetic field of the earth and towing and led
Line.Interaction between tether and magnetic field of the earth is generated available for the propulsive force for improving and reducing satellite altitude track.It is logical
Often, the interphase interaction in the magnetic field of tether and the earth produces propulsive force and causes this power to be used for while rise and drop satellite altitude track.
When needing to leave the right or normal track, the deployment unit of tether system by during the useful life of connected main spacecraft, protect by major part
Hold dormancy.Electric-powered tether has potentiality, but the active control of height is needed during disposing and leaving the right or normal track process in itself.
Pneumatic towing enhancing is related to the increase of air drag.Air drag or towing with height increase gradually it is thinning and
Reduce.This strategy that leaves the right or normal track is only limitted to LEO.This regional satellite experiences a fairly limited aerodynamics towing,
And because the reduction of satellite velocities caused by draught is very small.The system that aerodynamic drag can be strengthened adds air and dragged
Drag, make rate reduction of the speed of satellite to be left the right or normal track in required time to satellite.
Pull in strengthening system, towing sail is paid special attention to.Up to the present, the concept proposed is included by spacecraft
The compacting towing sail close to the position of target debris is transported, then the towing sail of compacting is connected on target debris, finally
Expanded to its final surface.This final surface will be responsible for producing towing to remove target debris from its initial position.
This towing surface is bigger, and device will directed overshoot fragment.In view of the space in spacecraft is limited, towing sail must be in its pressure
Loaded in real version, which has limited the maximum towing face of towing sail.
The advantages of passive towing Enhancement Method, is relevant with the simplicity of task in total figure, and each fragment institute to be removed
The payload amount needed is also less.Although this technology has had substantial amounts of research at present, specific method is not developed
Come the relation for ensuring surface area between the time that leaves the right or normal track.As the major requirement of each task, the time that leaves the right or normal track is principal element, with
The size of sail is perfectly correlated.The difficulty of towing sail size algorithm is：It is non-linear in the reduction of the orbit altitude for the phase that leaves the right or normal track
's.In view of being required for task, one simple method of research can be used for the correlation of any particular fragment of accurate optimization
Track element and its initial mass and cross section are very necessary.
The content of the invention
The purpose of the present invention is can be according to appointing than measures for towing sail area and the quality of particular fragment exploitation
Business requires, ensures the required sail size of any orbit time requirement, it is proposed that the towing region of fragment removing task to mass ratio
Towing enhancing measures.
This method core concept is：Relation between chip Natural Attenuation time and its initial mass with it is final it is desired from
Sail surface needed for the rail time is connected, and removes standard based on current fragment, and the towing sail designed by this method has been considered
For driving final equation；And this method typically has no effect on sail type, it can limit any design parameter for pulling sail to enter
One-step optimization design cycle；The similar tasks international standard of main space mechanism of the world is used, so any country's definition
Task can be calculated in this way.
The purpose of the method for the invention is to be achieved through the following technical solutions：
Step A, the towing sail data based on design, using power series data fitting method, are deduced reference area
With relational expression of the quality than parameter；
Step B, extraction preferably leaves the right or normal track the time, draws the UNIVERSAL COEFFICIENT expression formula of surface area and the final relation of quality；
Step C, the expression formula obtained by standard and step A and step B is handled by using existing fragment, i.e.,：Area with
Quality draws Ahmadloo than the UNIVERSAL COEFFICIENT expression formula of the final relation of relational expression and surface area and quality of parameter
Formula；
So far, from step A to step C, enhancing size is pulled in the towing region for completing fragment removing task to mass ratio
Method.
Based on above-mentioned steps A to step C, task is removed for specific fragment, towing region to mass ratio, which is pulled, to strengthen
The parameter calculation procedure of measures is as follows：
Step 1: the fragment to be removed is selected based on demand；
Step 2: the initial mass and cross-sectional area of one fragment to be removed of calculation procedure；
Should Step 3: being imitated for the fragment to be removed selected in step 1 based on the initial mass and cross section calculated
The Natural Attenuation time of fragment；
Step 4: using Natural Attenuation time and the required time value that leaves the right or normal track, step A to step C, and institute of the present invention are used
Method is stated to determine that the required of mission requirements leaves the right or normal track the time；
Step 5: obtain towing sail size using Ahmadloo inequality；
Step 6: verified based on towing sail time that leaves the right or normal track；
So far, from step 1 to step 6, complete and arrived using the towing region of fragment of the present invention removing task
Mass ratio towing enhancing measures calculate towing sail size, i.e. area and quality.
Beneficial effect
Enhancing measures are pulled in the towing region that fragment of the present invention removes task to mass ratio, with existing towing enhancing chi
Very little method is compared, and is had the advantages that：
1. inventive process provides a kind of very simple sail measures；
2. the method for the invention is applied to any chip size, and unrelated with towing sail type；
3. the method for the invention is can uniquely to calculate to pull sail section and quality only for the specific time that leaves the right or normal track
One method；
4. the method for the invention can further optimize according to specific towing sail type.
Brief description of the drawings
Following accompanying drawing is used for the visual towing region for expressing fragment removing task of the present invention to mass ratio
Towing enhancing measures simultaneously demonstrate the accuracy of this method.
What Fig. 1 was represented is the towing sail area and mass ratio of the latter design in table 1；
What Fig. 2 was represented is that matched curve and the data fitting of the towing sail based on selection are remaining；
What Fig. 3 was represented is the use process according to the method for the invention by step；
What Fig. 4 was represented is the SCOUT G-1 DEB Natural Attenuation time；
What Fig. 5 was represented is the METEOR 2-5 DEB Natural Attenuation time；
What Fig. 6 was represented is emulated using towing sail size of this method for -1DEB and METEOR 2-5 DEB.
Embodiment
The present invention is described in detail below in conjunction with drawings and examples, while also describes technical solution of the present invention
The technical problem and beneficial effect of solution, it should be pointed out that described embodiment is intended merely to facilitate the understanding of the present invention,
And any restriction effect is not played to it.
Embodiment 1
NASA's technical standard 8719.14 and the program of NASA's limitation orbit debris require (NPR
8715.6A) propose the space debris mitigation and a set of requirement in EOL disposal stages and standard of operation satellite.The standard and LEO
Environmental correclation, and unique this patent unique benefit embodiment of towing sail operating environment and property because needed for.NASA technical standards
8719.14 point out, LEO satellite should be deleted after EOL in 25 years, and are no more than 30 years after transmitting.Perigee altitude is less than
600 kilometers of object need not carry out track removing according to atmospheric pressure less than this height.Fragment of the height more than 700 (km)
It is their subject matters for centuries.
In order to formulate final equation, it is contemplated that the set of the similar tasks of design.2010, NASA was proposed 3U
NanoSail-D2 cubes, gross mass 4kg, the towing sails of 9 square meters is deployed on 640 kilometers of circuit orbits.
European Space Agency according to 25 years leave the right or normal track stage design and analyze Goss thayer Deorbiter Orbcomm it is broken
Piece, towing sail quality are 2.5 kilograms, and surface is 12 square metres.Compared with single propellant and double propellants, Gossamer
Deorbiter performance is respectively 55-70% and 14-39%.Space center of Surrey of Surrey Roehampton develops DeOrbitSail
FP7, by using DLR hairspring structural research, can reach gross weight for 3.4 kilograms as Cubesat poster presentation tasks
16 square metres of size.TechDemoSat-1 is the show-how satellite subsidized by Britain, and its use leaves the right or normal track wind EOL processing
Stage, mass ratio are 0.7 (m2/kg).CanX-7 (Canada advanced nanometer Satellite Experiment 7) is developed, with prove it is light-duty and
Low cost can dispose the feasibility of towing sail.Conceptual design is based on the requirement of the inter-agency space junk coordination committee (IADC),
Wherein 0.9 (kg) to 4.2 (square meter) sail size attribute.InflateSail is a 3U Cubesat, will be in QB50 in the works
Release, with feasibility of the displaying inflation sail in space.By using the inflation ring surface frame frame of 3 rice diameters, the gross area is designed as
10 square metres.Distributed spacecraft system technical research institute of Beijing Institute of Technology has designed a kind of using telescopic arm and scalable
The size of film can use towing sail, and multiple fragments, a parent space flight can be aimed in the individual task on different tracks
Device can carry up to 5 different towing sails and 5 fragments are removed in a subtask.The detailed area of all above-mentioned towing sails and
Quality provides in table 1 below and Fig. 1.
Table1.Selected designed drag sails information
It will be seen from figure 1 that by using power series, generally extractable towing sail area and relationship between quality.Unlimited power
The Section 2 of series has been used for data fitting, and power series is represented by equation below (1)：
Equation below (2) can also be further expressed as：
And bn(x-a)kRepresent single item, the center of a power values of series；For the neighborhood of the data of the circle with radius r
Value, can be according to following formula (3) design factor：
Wherein, the definition of r values is the convergence region of fitting data.This method is very simple in practice, but restrains slow.
Matlab data Fitting Toolbox has been used for the final curves fitting for obtaining above-mentioned data.The form meter of (4) as follows
The quality area equation of calculation is：
F (x)=axb+c (4)
Coefficient a, b and c (and their acceptable scopes), compared with quality, based on towing sail data set reference area
It is more important, draw following coefficient a, b and c predictive coefficient：
A=4.355 (- 15.29,24)
B=0.7731 (- 0.476,2.022)
C=1.466 (- 30,32.93)
In order to preferably be fitted accurate parameters, for predicting, i.e., accurate parameter value is preferably fitted.Formula (3) it is square
Root error (RMSE) is equal to 11.4, R squares, i.e.,：Related square between predicted value and response is 0.98.
Fig. 2 shows the residual error of matched curve and each data point.Approximating method depends on being chosen for simulating
Data set, and can somewhat change to estimate another group of higher precision of data.
Below, T1And T2It is the fragment Natural Survival time without towing sail and leaving the right or normal track the time with towing sail respectively.Root
According to above-mentioned requirements, it is also contemplated that be used for the maximum weight for pulling sail, can only have the 30% of target debris quality or main spacecraft
Imitate 30% processing time as decision of load, it is as follows：
T2≤30years&MDragSail≤0.3M1
And A1, M1And A2, M2It is the initial area, quality and enhancing area of fragment, chip quality includes the towing adhered to
Sail.Being defined as the key factor of AtM delta ratios should be maintained at below the inverse proportion for reducing the time, equation below (5)：
Relation between area and quality can be write as：
A2=A1+ADragSail (6)
M2=M1+MDragSail (7)
Bring formula (6) and (7) into formula (5), obtain equation below (8)：
Formula (3), the relation between the area of sail and quality of pulling just are changed into formula below (9)：
ADragSail=a (MDragSall)b+c (9)
Bring formula (9) into formula (8), draw final optimization AtM ratios, i.e.,：Ai Madeluo inequality, public affairs below
Formula (10)：
By selecting initial chip mass scope, 1/3rd of gross payload can be reached plus towboat quality,
The towing canvas region of optimization can be obtained.Occurrence for making the null quality of above-mentioned inequality, it is possible to achieve selected
The optimization size for the time that leaves the right or normal track selected.
Towing sail size is calculated according to the inequality of Ahmed Lip river and carries out chip sample.For these fragments and Fig. 3
Also the step of identical is mentioned has been have followed.From figure 3, it can be seen that in the selection chip to be removed and simulate its Natural Attenuation
After time, Ai Madeluo inequality can calculate the appropriate of any time that leaves the right or normal track and drag sail size and 2-5DEB to be based on track mould
Intend.
Two selected fragments are METEOR 2-5DEB and SCOUT G-1DEB.Table 2 below is the broken of two selections of emulation
Piece.
The fragment for two selections that table 2 emulates
First, the Natural Attenuation time is that the Encke methods based on ENTEOR 2-5 DEB and SCOUT G-1 DEB calculate
(Fig. 4 and Fig. 5).
From fig. 4, it can be seen that the Natural Attenuation time is the time change of the SCOUT G-1 DEB of 48643 days half main shaft；
From fig. 5, it can be seen that the Natural Attenuation time based on METEOR 2-5 DEB is the orbital simulation of 60124 days.
Then, according to the 25 of Ahmadloo years orbit time inequality, sail size is calculated to prove the accurate of this method
Property, it is as shown in table 3 below：
The sail size that table 3 calculates according to Ahmadloo inequality
| Leave the right or normal track the time | ADragSail(m2) | MDragSail(kg) |
| 25 years (SCOUT G-1) | 11.371 | 2.8947 |
| 25 years (METEOR 2-5) | 15.520 | 4.551 |
Table 3 shows leaving the right or normal track the cycle for 25 years for the patented method calculating based on METEOR 2-5 and SCOUT G-1 fragments
Towing sail area and quality.
According to the calculating parameter of the towing sail of each time that leaves the right or normal track, the orbital simulation of connection towing sail and fragment is repeated, is made
Proved for the accuracy of this method.Final result proves, calculates size by pulling sail, meets required leave the right or normal track the time (Fig. 6),
It is as shown in table 4 below.
Table 4 calculates leaving the right or normal track the time of obtaining of size by pulling sail
| Preliminary project leaves the right or normal track the time (year) | SCOUT G-1 DEB (year) | METEOR 2-5 DEB (year) |
| 25 | 21.89 | 23.31 |
From fig. 6, it can be seen that SCOUT G-1 track run time is 21.89, METEOR 2-5 are 23.31
(8488 days) (last part of curve shows final track run time).These values of leaving the right or normal track are display methods accuracys
Parameter, because they were less than 25 years.As long as the time that leaves the right or normal track is less than the original plan time, it means that the method that this patent proposes
It is accurate.
Above-described specific descriptions, the purpose, technical scheme and beneficial effect of invention are carried out further specifically
It is bright, it should be understood that the specific embodiment that the foregoing is only the present invention, the protection model being not intended to limit the present invention
Enclose, within the spirit and principles of the invention, any modification, equivalent substitution and improvements done etc., should be included in the present invention
Protection domain within.
Claims (3)
1. enhancing measures are pulled in the towing region that fragment removes task to mass ratio, it is characterised in that：Core concept is：It is broken
Relation between bits Natural Attenuation time and its initial mass is connected with the final desired sail surface to leave the right or normal track needed for the time, and base
Standard is removed in current fragment, the towing sail designed by this method has been considered for driving final equation；And this method one
As have no effect on sail type, it can limit it is any towing sail design parameter circulated with further optimization design；Generation is used
The similar tasks international standard of main space mechanism of boundary, so the task of any country's definition can be carried out in this way
Calculate.
2. enhancing measures are pulled in the towing region that fragment according to claim 1 removes task to mass ratio, it is special
Sign is：Comprise the following steps：
Step A, the towing sail data based on design, using power series data fitting method, are deduced reference area and matter
Measure the relational expression than parameter；
Step B, extraction preferably leaves the right or normal track the time, draws the UNIVERSAL COEFFICIENT expression formula of surface area and the final relation of quality；
Step C, the expression formula obtained by standard and step A and step B is handled by using existing fragment, i.e.,：Area and quality
Than the UNIVERSAL COEFFICIENT expression formula of the final relation of relational expression and surface area and quality of parameter, Ahmadloo inequality is drawn；
So far, from step A to step D, enhancing measures are pulled in the towing region for completing fragment removing task to mass ratio.
3. enhancing measures are pulled in the towing region that fragment according to claim 2 removes task to mass ratio, it is special
Sign is：Based on above-mentioned steps A to step C, task is removed for specific fragment, enhancing chi is pulled in towing region to mass ratio
The parameter calculation procedure of very little method is as follows：
Step 1: the fragment to be removed is selected based on demand；
Step 2: the initial mass and cross-sectional area of one fragment to be removed of calculation procedure；
Step 3: the fragment is imitated based on the initial mass and cross section calculated for the fragment to be removed selected in step 1
The Natural Attenuation time；
Step 4: using Natural Attenuation time and the required time value that leaves the right or normal track, step A to step C, and side of the present invention are used
Method come determine mission requirements needed for leave the right or normal track the time；
Step 5: obtain towing sail size using Ahmadloo inequality；
Step 6: verified based on towing sail time that leaves the right or normal track；
So far, from step 1 to step 6, complete and the towing region of task is removed to quality using fragment of the present invention
Towing sail size, i.e. area and quality are calculated than towing enhancing measures.
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