JPH05254500A - Detection and pulverizing method for space floating object - Google Patents

Abstract

PURPOSE:To facilitate detection of the position of a fragment so as to source pulverization by transmitting a command containing distance measurement information to an artificial satellite and a beam for detecting a floating object, computing and detecting the position of the floating object, and irradiating the floating object with laser for pulverizing after necessity for pulverizing a floating object and a risk are discussed with a control station on the ground. CONSTITUTION:Simultaneously with transmission of research radio wave 5 from transmission equipment 3, a command 7 containing distance measurement information is transmitted from a control station 4 to an artificial satellite 2. The artificial satellite 2 detects a distance (a phase difference) from distance measurement information for scattered waves 6 and distance measurement information of the received command 7. Based on position data of the fragment 1, the artificial satellite is made to approach the fragment 1, and image data of the fragment by means of an optical sensor mounted on the artificial satellite is transmitted as telemetry 8 to the control station 4. Necessity for the fragment 1 to be pulverized and a risk are decided by the control station 4 based on image data, and when the fragment is pulverized, pulverization execution is contained in the command 7 for transmission. The artificial satellite 2 irradiates the fragment with laser beams 9 for pulverization.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for detecting and crushing debris floating in outer space.

[0002]

2. Description of the Related Art Debris floating in space (Debris)
Conventionally, a radar has been used to detect s) (hereinafter referred to as "fragments"). The debris does not carry the transponder found on satellites, so the primary radar must be used. FIG. 7 shows the structure of a primary radar. In the figure, 62 is a radar, 63 is a transmitted wave, 64 is a reflected wave, and 1 is a fragment.

A radar 62 irradiates a target fragment with a radio wave 63 whose beam is focused by an antenna having a high gain. This radio wave has an effective cross-sectional area (Cross Sectio)
A reflected wave (Echo) proportional to n) is generated, and this scattered wave is received by the radar 62 again. Since such radar transmission / reception is carried out on the ground facility, image acquisition of fragments and crushing of fragments are not performed.

[0004]

[Equation 1]

[0005]

The above-mentioned "Equation 1" is applied to the characteristics of the primary radar. In this application example, the existence region of the debris exists at a higher altitude than around 200 Km, so the received power of the radar is attenuated in proportion to the fourth power of R and becomes weak. For this, it is necessary to increase the transmission power and increase the antenna gain,
In order to realize it, the hardware becomes large, so various problems occur. For example, an increase in transmission power leads to an increase in the size of a transmission device. Among them, the method of repeatedly transmitting pulses is because the fragments are orbiting at an altitude above about 200 km, so that the beam of the radio wave can be reached within 200 km from the ground. Does not use power effectively, as it spreads ineffectively. Further, the actual image of the fragment is unknown only by detecting the fragment separated by 200 km or more by the radar, and the fragment is not crushed.

The present invention has been made to solve the above problems, and it is necessary to easily detect the position of the debris floating in outer space and to detect the real image of the debris. It is intended to provide crushing of debris after judging the danger.

[0007]

A method for detecting space suspended matter according to the present invention is provided with a plurality of artificial satellites with a phase difference in the same orbit at an orbital altitude of 200 km to 250 km, and a receiving device or a transmitting device. , A transmitter and a controller on the ground are combined, and a transmitter / receiver system that combines them is configured, and since transmission and reception are separated, continuous waves can be easily used for search radio waves, and almost the same. Since a satellite is highly intervened, this satellite has a navigation guidance function, an image processing function, and a radar crushing device to approach the debris and obtain an image of the debris, and the necessity and danger of crushing It is possible to crush the debris after judging the sex, and the probability of detection of space suspended matter is increased by multiple satellites.

[0008]

In the present invention, since the search radio wave is detected by propagation of the radio wave in only one direction, R of "Equation 1" can be shortened equivalently, and the transmission and reception are separated, so that the continuous wave is searched for. Can be used for In addition, the navigation guidance of the artificial satellite is performed based on the detected position data of the fragment and the position and attitude data of the artificial satellite, and after approaching to a certain distance, the radar transceiver mounted on the artificial satellite is used Approach while detecting position data,
The actual image of the fragment is detected by capturing an image of the fragment with an artificial satellite camera from a very short distance. Also, the image data acquired by the artificial satellite is transmitted to the ground by telemetry, and it becomes possible to crush the fragments by laser irradiation of the artificial satellite by a command from the ground after judging the necessity and danger of crushing the fragments on the ground. .. Also, by introducing multiple artificial satellites, it is possible to transmit and receive with any one of the artificial satellites at all times, thereby increasing the detection probability of space suspended matter.

[0009]

【Example】

Example 1 The basic configuration of the present invention is shown in FIG. In the figure, 1 is a fragment, 2 is an artificial satellite among a plurality of artificial satellites, 3 is transmission equipment,
4 is a control station, 5 is a search radio wave of the fragment 1 transmitted from the transmission equipment 4, 6 is a scattered wave after being scattered by the fragment 1, 7 is a command from the control station to the artificial satellite, 8 is from the artificial satellite to the control station , And 9 is a laser beam.

The artificial satellite 2 is placed in an orbit suitable for observing the fragment 1. The search radio wave 5 of the fragment 1 is transmitted from the transmission equipment 3. When the search radio wave 5 is irradiated on the fragment 1, the scattered wave 6 is scattered according to the effective area of the fragment, and the scattered wave 6 is generated by the artificial satellite 2
Received by. It is assumed that the search radio wave transmission azimuth angle (azimuth angle) and elevation angle (elevation angle) when the scattered wave 6 is received by the artificial satellite 2 can be set with high accuracy. At the same time as transmitting the search radio wave 5 from the transmission equipment 3, the control station 4 transmits the command 7 including the distance measurement information to the artificial satellite 2 The distance measurement information of the scattered wave 6 received from the artificial satellite 2 and the distance measurement of the received command 7 The distance (phase difference) can be detected from the information. Since the orbit of the artificial satellite 2 can be accurately determined by the control station 4, the position of the fragment can be obtained with high accuracy if the time is known. In addition, based on the detected position data of the debris, the artificial satellite is guided by navigation, approached to the debris, the image data of the debris is acquired by the optical sensor mounted on the artificial satellite, and this image data is used as the telemetry 8 control station. Send to 4. The control station 4 judges the necessity and risk of crushing the fragment 1 based on the image data, and when crushing, sends a command 7 including a crushing execution command. Upon receiving the crushing execution command, the artificial satellite 2 focuses the laser on the fragment and irradiates the laser beam 9 to crush the fragment.

A pseudo random noise code (Psuedo Random Noise code, abbreviated as PN code) is used for the distance measurement information of the command, and a continuous wave similarly modulated to the pseudo random noise code is used for the search radio wave. The relationship between the PN code of the command 10 and the PN code of the scattered wave 11 received by the artificial satellite 2 is shown in FIG. Reference numeral 10 is a command, 11 is a PN code serving as distance measurement information of scattered waves, and 12 and 13 are one block of the PN code. 14 is the propagation delay time between the command and the scattered wave.

Blocks of PN code 12 and 13 are i,
It is a pseudo-random code such as j and k, and is actually formed by a series of combinations of 0 and 1 shown in the figure. The lengths of 0 and 1 are values determined by selecting the type of PN code, and all the character lengths of i, j, k ..., A are the same, and one block is formed by connecting these characters consecutively. There is. The artificial satellite 2 is equipped with this PN code correlator,
The phases of the PN code 10 of the command and the PN code 11 of the scattered wave can be read. By comparing the two phase differences, the time delay 14 between the command 10 and the scattered wave 11 can be detected.

Since the positions of the artificial satellite 2 and the transmitting equipment 3 are known and the time delay between the two codes is known, this relationship is represented in FIG. 3 by a simple geometric model. 15 in the figure
Is the x-axis, 16 is the y-axis, 17 and 18 are the focal points of the ellipse, 19 is the ellipse, 20 is a line segment connecting the points on the ellipse and the two focal points, 21
Is a point on the ellipse, 22 is the direction of the fragment 1 viewed from point A, 2
3 is the position of the fragment 1.

Assuming that the position of the artificial satellite 2 is B point 18 and the position of the transmission equipment 3 is A point 17, the x-axis 15 can be defined as a line segment penetrating both. The distance between AB is known from the orbit determination. The distance between the transmission equipment 3, the fragment 1 and the path of the artificial satellite 2 is the distance difference delay time which is the difference between the time corresponding to the distance between AB and the time when the scattered wave 6 reaches the artificial satellite 2 via the search radio wave 5. It can be obtained from the sum of the distance corresponding to 14 and the distance between AB. The following composition can be created from these two distances. That is, the point A17 and the point B18, which are separated by the distance between the artificial satellite 2 and the transmission equipment 3, are focused, and one point P'on the ellipse
An ellipse 19 can be drawn such that 21 is the sum of the distance corresponding to the distance difference delay time 14 and the distance between AB. Considering in two dimensions, the fragment 1 exists on this ellipse. Since it is actually three-dimensional, the fragment 1 has an ellipse 19 of x
It can be seen that it exists on the surface of the spheroid that is formed when it is rotated about the axis. On the other hand, A point 17 assumes the transmission equipment 3,
Two pieces of angle information, that is, the azimuth setting and the elevation angle of irradiation of the search radio wave 5 from the transmission equipment 3 to the fragment 1 are obtained. Therefore, point A 1
When a straight line is drawn in the irradiation direction 22 from 7 and the intersection point P23 with the spheroid described above is obtained, this P point 23 is the position of the fragment 1.

FIG. 4 shows a circuit configuration for detecting a distance difference in the artificial satellite 2. 24 is an antenna for receiving the scattered wave 6,
Reference numeral 25 is a command receiving antenna, 26 and 27 are receivers, 30 and 31 are local PN code generators, 28 and 29 are comparison circuits, 32 and 33 are integrators and code tracking circuits, and 34 is a code difference detection. Circuit.

The antenna 24 receives the scattered wave 6 and obtains a video output from the carrier wave received by the receiver 26. This output is the same P that the transmission equipment 3 and the control station 4 have.
The output of a local PN code generator 30 composed of N codes is compared, the strength of the correlation is detected by a comparison circuit 28, and the acquisition of the code and the tracking of the code are performed by an integrator and the code tracking circuit 32. .. Similarly antenna 2
5 receives the command 7, the receiver 27, the comparison circuit 29,
Integrator and code tracking circuit 33, local PN code generator 31
Thus, processing similar to the above-mentioned scattering is performed. For both codes, the local PN code generators 30 and 31 after achieving the acquisition always show the same phase as the received code. Therefore, by inputting the PN code to the code difference detection circuit 34, the command 7 and the scattered The phase difference between the waves 6, ie the distance difference, can be detected.

FIG. 5 is a summary of the position detection algorithm of the fragment 1. 35 is the detection time, 36 is the distance difference data of the scattered wave command, 37 is the position data of the control station, 38
Is the position data of the transmitting equipment, 39 is the position data of the satellite obtained by GPSR, 40 is the irradiation azimuth and elevation data of the search radio waves, 41 is the distance between the control station and the artificial satellite, and the distance from the transmitting equipment to the satellite. Correction data to correct, 42
Is the distance data between the transmitting equipment and the artificial satellite, 43 is the distance difference data after being corrected by the correction data 41, 44 is the three-dimensional elliptic equation, and 45 is the position data of the fragments.

To detect the position of the 45 fragments, 42
Of the distance from the transmitting equipment to the artificial satellite, the distance difference data between the distance from the transmitting equipment of 43 to the artificial satellite and the distance from the transmitting equipment to the artificial satellite via the fragment, and the search radio wave of the transmitting equipment of 40. Irradiation direction is required. When these three data are used in the calculation, the detection designated time 35 is determined as the designated value, and the calculation is performed by the data at the specific time. The position of the artificial satellite 2 is GPS
It is obtained from the satellite position data 39 obtained by R and the detection time 35. From this data, the position data 37 of the control station 4 and the position data 38 of the transmission equipment 3, the control station 4
And correction data 41 for correcting the distance of the artificial satellite 2 to the distance of the artificial satellite 2 from the transmitting equipment 3 and the distance data 42 from the transmitting equipment 3 to the artificial satellite 2 are obtained. The distance difference data 36 between the scattered wave 6 and the command 7 is corrected to the distance difference data 43 between the distance from the transmitting equipment 3 to the artificial satellite 2 and the distance from the transmitting equipment 3 to the artificial satellite via the fragment by the correction data of 41. To be done. A solid ellipse equation 44 is obtained from the distance data 42 from the transmission equipment 3 to the artificial satellite 2 and the corrected distance difference data 43, and is determined by the solid ellipse equation 44 and the irradiation azimuth and elevation angle data 40 of the search radio wave 5. The position 45 of the debris, which is the intersection with the straight line, can be obtained.

In FIG. 6, after detecting the position of the fragment by the artificial satellite, the transmission equipment, and the transmission / reception system of the control station, the artificial navigation approach of the artificial satellite approaches the fragment, and the image data of the fragment is acquired and telemetry transmitted. When the command to crush the fragments is sent from the control station, the process flow until the fragments are irradiated with the laser beam is shown.
In the figure, 46 is a tracking command, 47 is processing of on-board software that sets the time, control method and control amount of the orbit control maneuver, 48 is relative position data of artificial satellite and fragments, 4
9 is the orbit control, 50 is the first approach completion status,
Reference numeral 51 is attitude data from an attitude sensor, 52 is relative attitude data of fragments in a radar coordinate system, 53 is attitude control by an actuator, 54 is detection of fragments by the radar and approach navigation guidance to the fragments, 55 is a final approach completion status, 56 Is image processing of fragments, 57 is telemetry of image data, 58 is a fragment crushing execution command, 59 is laser aiming control, 60 is aiming coincidence, and 61 is laser irradiation.

After detecting the debris position data of 45, it is judged whether the debris position can be tracked by the artificial satellite, or whether the debris position can be returned to the original orbit by a simple control without largely deviating from the orbits of other artificial satellites. Then, the tracking command 45 is transmitted from the control station. In the software installed on the artificial satellite by the tracking command, the relative position data 4 by the detection time 35, the artificial satellite position data 39, and the fragment position data 45
8 and the orbit control maneuver time, method, and control amount calculation 47 for the artificial satellite to approach the debris. 47
The orbit control 49 is carried out according to. When the debris approaches the relative position where it can be sufficiently detected by the radar mounted on the artificial satellite, the first approach completion status 50 is turned on. When the first approach completion status 50 is turned on, the direction (relative attitude) of the fragment in the radar coordinate system of the artificial satellite is calculated, and the attitude control 53 is executed to direct the sensitivity axis of the radar to the fragment. When the radar catches the debris, the navigation control and attitude control 54 is executed to a position and attitude suitable for taking an image. When the position and posture are suitable for taking an image, the final approach completion status 55 is turned on, and the image processing 56 of the fragments is performed. The image data of the fragments is transmitted as telemetry 57 to the control station, and the control station determines the necessity and risk of fragmentation from the image data. When the control station transmits a command 58 for instructing the crushing and the artificial satellite receives the command, the software installed on the artificial satellite performs a control 59 for adjusting the laser aiming at the fragment.
Laser irradiation 6 when aiming status 60 is turned on 6
1 is performed.

A plurality of artificial satellites based on the above-described embodiment are injected into the orbits near many debris in which the phases are changed.
The control station and individual satellites are limited in visible time, but the control station can transmit and receive to and from another satellite one after another.

[0022]

The present invention has the following effects.

The orbit of the artificial satellite is set in the vicinity of the orbiting debris floating in outer space, and a command including ranging information is transmitted from the control station to the artificial satellite, and similarly search radio waves are transmitted from the transmitting equipment to the debris. Since the position of the debris is obtained by the combination of one-way radio wave propagation detection, the R ⁴ term in the above-mentioned “Equation 1” that represents the received power density due to the bidirectional radio wave propagation to the debris becomes large and the radio wave becomes invalid. It is possible to easily detect the position of a fragment even at an orbital height at which the area spreads.

Furthermore, the navigation guidance function and the image processing function of the artificial satellite can take an image of debris from a close range, and from this image data, the substance of the debris, the necessity of crushing the debris, and the danger of crushing the debris. The fragment can be crushed by a laser beam after determining the sex.

Furthermore, by using a plurality of artificial satellites having different phases, it is possible to detect fragments at any time, and the detection probability increases.

[Brief description of drawings]

FIG. 1 is a basic configuration of the present invention.

FIG. 2 is a diagram showing a relationship between a command and a PN code of a scattered wave.

FIG. 3 is a diagram showing a geometric model of a transmission facility, an artificial satellite, and fragments.

FIG. 4 is a diagram showing a circuit configuration for detecting a distance difference in an artificial satellite.

FIG. 5 is a diagram showing a fragment position detection algorithm.

FIG. 6 is a diagram showing a process flow until a fragment is approached and image data of the fragment is acquired by an autonomous navigation guidance function of an artificial satellite.

FIG. 7 is a diagram showing a configuration of a conventional primary radar.

[Explanation of symbols]

 1 Fragment 2 Artificial Satellite 3 Transmission Equipment 4 Control Station 5 Search Radio Wave 6 Scattered Wave 7 Command 8 Telemetry 9 Laser Beam 10 PN Code of Command 11 PN Code of Scattered Wave 12 PN Code 1 Block of Command 13 PN Code 1 Block of Scattered Wave 14 Propagation delay time between command and scattered wave 15 X-axis 16 Y-axis 17 Focus point A of ellipse 18 Focus point B of ellipse 19 Ellipse 20 Line segment connecting two foci of ellipse 21 Point on ellipse 22 A point Direction of fragment as seen from 23 Fragment position 24 Scattered wave reception antenna 25 Command reception antenna 26 Scattered wave receiver 27 Command receiver 28 Scattered wave comparison circuit 29 Command comparison circuit 30 Scattered wave local PN code generation 31 Command local PN code generator 32 Scattered wave integrator and code tracking circuit 33 Command integrator And code tracking circuit 34 Detection circuit of code difference 35 Detection time 36 Distance data of scattered wave and command 37 Position data of control station 38 Position data of transmitting equipment 39 Position data of satellite obtained by GPSR 40 Irradiation of search propagation Direction 41 Correction data 42 Distance data between transmitting equipment and satellite 43 Distance difference data after correction by correction data 44 Solid elliptic equation 45 Fragment position data 46 Tracking command 47 Orbit control Maneuver time / method / control amount calculation 48 Relative position data of fragment and artificial satellite 49 Orbit control 50 First approach completion status 51 Attitude data of artificial satellite 52 Relative attitude data of fragment in radar coordinate system 53 Attitude control 54 Navigation guidance and attitude control by radar 55 Final approach completion status 56 image processing 57 image data Remetry 58 Grinding execution command 59 Laser aiming control 60 Aiming coincidence status 61 Laser irradiation

Claims (1)

[Claims] 1. A plurality of artificial satellites are introduced with a phase difference in orbit in the vicinity of the presence of space suspended matter, and a command including ranging information is transmitted to a visible artificial satellite from a ground control station,
At the same time, a beam with a frequency different from the command containing distance measurement information is emitted in the direction in which a floating object is detected, and the effective radio wave of the space floating object generated when this beam is irradiated with the space floating object. The scattered wave corresponding to the cross-sectional area is received by the artificial satellite, and the data of the distance difference obtained from the phase difference between the command and the scattered wave on the artificial satellite and the satellite separately obtained by the control station. Position data and the beam irradiation direction at the transmitting station are used as input to detect the position of space suspended matter, and if it is a position that can return to the original orbit based on this detected position data. An artificial satellite is navigated to approach a space floating object, and at the final approach, a radar transceiver mounted on the artificial satellite approaches to a close range, and the image of the space floating object is mounted on the artificial satellite. An optical sensor acquires and sends this image data to the control station, and the control station on the ground judges the necessity and danger of crushing space suspended matter.In that case, the control station sends a command to the artificial satellite and the satellite A method for detecting and crushing space suspended matter characterized by irradiating a space suspended matter with a laser and crushing.