KR100198792B1 - The structure and driving method of real-time satellite simulator using a shared memory - Google Patents

Abstract

The simulator of single process structure has problems such as development and maintenance, and the simulator of multi-processor structure does not satisfy the real-time requirements. The disadvantage of the prior art is that the simulator of shared memory and multi- A real-time satellite simulator structure and driving method using a unique memory that minimizes a time required for real-time operation, facilitates maintenance and correction development, and realizes real-time operation.

Description

Real-time satellite simulator architecture and method using shared memory

The present invention relates to a satellite simulator, and more particularly, to a structure and a driving method of a real-time satellite simulator using a shared memory.

A satellite simulator using a single process structure used in European countries is used as a driving method of a conventional real-time satellite simulator system. This is a fast process, but it is not easy to develop and maintain because it is a single process. In addition, since the multi-process architecture used in the United States does not use shared memory, it is difficult to satisfy real-time requirements because frequent internal data transmission must be performed.

As described above, although the satellite simulator using the conventional single process structure has a high execution speed, it is not easy to develop and maintain because it is a single process. Since the satellite simulator using the multi-process structure does not use the shared memory, It is difficult to satisfy real-time requirements because internal data transmission must be performed.

Accordingly, the present invention for solving the above problems minimizes the time required for exchanging data between processes by using a shared memory, maintains a multi-process structure, facilitates subsequent maintenance and modification development, The purpose of this paper is to provide a structure and a driving method of a more advanced satellite simulator.

According to an aspect of the present invention, there is provided a real-time satellite simulator using a shared memory. The real-time satellite simulator includes a satellite attitude and orbit state data region, a meter state data region, a thermal control system state data region, Memory, hardware operator console and hard disk, input initial data from the hard disk to initialize the satellite state data, and execute the posture and orbit control system simulation process, the meter simulation process, the thermal control system simulation process, the remote measurement processing process and the remote command An operator access process for starting the processing process, reading data in the telemetry data area, modifying the remote command data area and terminating the respective processes; An attitude and orbit control system process for reading the data of the state data area and the power meter state data area and correcting the attitude and orbit state data area and the telemetry data area by calculating a new attitude, A watt-hour simulation process for reading the data of the region, the satellite attitude and orbit state data region and the thermal control system state data region, calculating the new state of the wattmeter and the remote measurement value and then modifying the wattmetry state data region and the remote measurement data region, A thermal control system simulation process for reading the data of the command data region, the satellite attitude and orbit state data region and the meter state data region, calculating new heat generation amount and telemetry value, and then correcting the thermal control system state data region and telemetry data region And the circle A remote measurement process of reading the data of the measurement data area and constructing a telemetry frame, and then transmitting the telemetry frame to the operator via the LAN interface; and, when a new remote command arrives from the operator through the LAN interface, And a command processing process.

In order to achieve the above object, a method for driving a real-time satellite simulator using a memory according to the present invention initializes satellite state data in an operator connection processing process for inputting initial data from a hardware hard disk, The method comprising the steps of: initiating a process, a power meter simulation process, a thermal control system simulation process, a telemetry process process, and a remote command process process; And modifying the satellite attitude and orbit state data region and the telemetry data region after calculating a new attitude, orbital state, and telemetry values in the orbit control system simulation process,Modifying a power meter state data region and a telemetry data region after calculating a new power meter state and a telemetry value in the power meter simulation process that has read data in the inverse and thermal control system state data region; Correcting the thermal control system status data area and the remote measurement data area after calculating a new thermal control system status and a remote measurement value in the thermal control system simulation process of reading the data of the attitude and orbit status data area and the power meter status data area, The method comprising the steps of: constructing a telemetry frame in a telemetry process for reading data in the telemetry data region and telemetry data region and transmitting the telemetry frame to an operator via a LAN interface; receiving a new telemetry command from the operator via the LAN interface; remote Command process stored in the process stage and, for the current satellite state upon receiving end command simulator data for modifying the remote command data area on the hard disk, and is characterized in that eojin achieved by the step of terminating the respective process.

FIG. 1 is a hardware block diagram of a satellite simulator system to which the present invention is applied; FIG.

FIG. 2 is a flow chart showing a method of driving a real-time satellite simulator according to the present invention;

FIG. 3 is a processing flowchart of an operator connection processing process according to the present invention; FIG.

Figure 4 is a flow chart of the process of the attitude and control system simulation process according to the present invention.

FIG. 5 is a flowchart of a process of the power meter simulation process according to the present invention; FIG.

6 is a processing flow diagram of a thermal control simulation process according to the present invention.

7 is a process flow diagram of a telemetry process according to the present invention.

Figure 8 is a processing flow diagram of a remote command process according to the present invention;

DESCRIPTION OF THE REFERENCE NUMERALS

1: Operator console 2: LAN interface

3: Satellite simulator 4: Hard disk

5: Satellite simulator workstation

221: Operator connection processing process 222: Remote measurement processing process

223: Remote command processing process

224: satellite state and orbital state data area

225: Power meter status data area 226: Thermal control system status data area

227: remote measurement data area 228: remote command data area

229: Posture and orbit control system simulation process

230: Wattmeter simulation process 231: Thermal control system simulation process

232: Shared memory

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a system hardware configuration diagram to which the present invention is applied. Its operation will be described as follows. The satellite simulator 3 is connected to the operator console 1 through a connection cable 14 to receive the operator's input and output the status of the simulator to the screen. The remote command message 12 is input to the satellite simulator 3 via the LAN interface 2 using the LAN connection cable 11. [ The telemetry message 13 is output from the satellite simulator 3 to the external operator and the operator console via the LAN interface 2 and the LAN connection cable 11. [ An external operator can use the LAN to issue remote commands to the simulator and remote measurements through the LAN. At the start of the simulator, the satellite simulator 3 reads the initial data 16 stored in the hard disk 4 to initialize the data. The satellite simulator 3 stores the satellite status data 15 at the end of the simulator in the hard disk 4. [

FIG. 2 is a flow chart illustrating a method of driving a satellite simulator according to the present invention. Each process shares a data area in shared memory is as follows.

The operator accesses the initial data (16) and initializes the data in the shared memory (232) by the connection processing process (221).

The attitude and orbit control system simulation process 229 reads satellite attitude and orbital state data in the satellite attitude and orbital state data area 224 209 and sends satellite remote command data in the satellite remote command data area 228 And records the updated satellite attitude and orbital state data in the satellite attitude and orbital state data area 224 of the shared memory 232 (208) and the telemetry data area 227 And records the updated telemetry data at 218. [

The power meter simulation process 230 reads satellite attitude and orbit data from the satellite attitude and orbit state data area 224 and reads 213 the satellite meter data from the satellite meter field data area 225, (219) reads the remote control data of the satellite from the remote control data area (228) of the satellite (219), calculates the current state of the power system, and reads the remote control data from the shared memory (218) the updated telemetry data in the telemetry data area (227) by recording the updated meteorological data in the meteorological data area (225) of the telemetry data area (232).

The thermal control system simulation process 231 reads the satellite attitude and orbit data from the satellite attitude and orbit state data area 224 and reads the satellite meter data from the satellite meter data area 225 ) Reads the thermal control system status data from the thermal control system status data area 228 of the satellite (216), reads the remote command data of the satellite from the remote command data area 228 of the satellite (219), calculates the current thermal control system status The updated thermal control system status data is recorded 217 in the thermal control system status data area 226 of the shared memory 232 and the updated telemetry data is recorded in the telemetry data area 227. [

The remote measurement processing process 222 reads the telemetry data of the satellite in the telemetry data area 227 of the satellite and outputs the telemetry frame via the LAN interface.

The remote command processing process 223 receives the remote command data via the LAN interface 12 and records the remote command data of the satellite in the remote command data area 228. At 206,

The operator connection processing process 221 reads and processes the telemetry data of the satellites in the telemetry data area 227 of the satellite 205 and is transmitted 14 for display to the operator console,

When the end command is received, the operator connection processing process 221 reads the data in the shared memory 232, stores the data in the disk 201, and terminates the entire process (15).

In this way, it is possible to satisfy the real - time performance requirements of the satellite simulator by carrying out frequent and large amount of data transmission and reception between processes through shared memory.

FIG. 3 is a processing flowchart of an operator connection processing process according to the present invention; FIG. (301) Posture and orbit control system simulation process, power meter simulation process, thermal control system simulation process, remote measurement processing process and remote command processing Initialize the process. (304) whether there is an operator input (303) and whether there is an operator input (304). If not, the remote command data is received / corrected (305) and again the operator input is confirmed. If there is no operator input, the remote measurement data is read and displayed on the screen (307). After waiting for a predetermined time (306), it is checked whether there is an operator input (303). If the operator input is a termination command in step 304, the process ends in the attitude and trajectory control system simulation process, the power meter simulation process, the thermal control system simulation process, the remote measurement process process, and the remote command process process. (308) By sharing satellite attitude and orbit data, telemetry data, and remote command data in memory, traffic between internal processes can be reduced.

FIG. 4 is a processing flowchart of the attitude and trajectory control system simulation process according to the present invention. When the simulation process starts, the remote command data is read from the shared memory area (401), and the actual time is compared with the simulator time (402). If the simulator time is ahead of the actual time, wait for a certain time 403) and returns to the step (402). If the actual time is ahead of the simulation time, the simulator time is increased by a fixed time (404), and the satellite attitude and orbit data is read from the shared memory area (405) .The new attitude and orbit state data and telemetry values (406). (407) Compares the actual time with the simulation time (408) and branches to step (404) if the actual time goes ahead of the simulation time. If the simulation time is ahead of the actual time, correct the telemetry data (409)

The posture and trajectory control system simulation process can reduce traffic between internal processes by sharing satellite attitude and orbit status data and remote command data in shared memory.

FIG. 5 is a processing flowchart of the power meter simulation process according to the present invention. When the power meter simulation process is started, the remote command data is read from the shared memory area (501) and the actual time is compared with the simulation time (502). If the simulator time is ahead of the actual time, (502). If the actual time goes ahead of the simulation time, the simulator time is increased by a predetermined time 504. The satellite posture and the orbit data are read from the shared memory area 505, and the thermal control system status data is read from the shared memory area 506 (507) modifying the meter state data of the shared memory area (508) comparing the actual time with the simulation time (509), the actual time is ahead of the simulation time If the simulation time is ahead of the actual time, the remote measurement data is corrected (510). The power meter simulation process shares thermal control system data with the satellite attitude and orbit data in the shared memory, The traffic between them can be reduced.

6 is a flow chart of the thermal control system simulation process according to the present invention. When the thermal control system simulation process is started, the remote command data is read from the shared memory area. (601) The simulation time is compared with the actual time (602). If the simulator time is ahead of the actual time, (602). If the actual time is ahead of the simulation time, the simulator time is increased by a predetermined time 604. The satellite posture and orbit data are read from the shared memory area 605, and the power meter data is read from the shared memory area 606 The thermal control system status data and telemetry values are calculated 607 and the thermal control status data is modified 608. If the actual time is ahead of the simulation time by comparing the current time with the simulation time 609, (610) The thermal control system simulation process reduces the traffic between internal processes by sharing the satellite attitude and orbit status data and the meter status data in the shared memory. .

(701) reads telemetry data from a shared memory area (702), reads the telemetry data from the shared memory area (702), reads the telemetry data from the shared memory area The remote measurement command data and the telemetry tape are reconstructed to generate a telemetry frame 703, a telemetry frame is transmitted 704, a predetermined time is elapsed 705, and the flow branches to step 701. [

The telemetry processing process can reduce traffic between internal processes by sharing telemetry data in shared memory.

FIG. 8 is a flowchart of a remote command processing process according to the present invention; FIG. If the remote command processing process is started, the process waits until a new remote command is received (801). If a new remote command arrives, the remote command data is modified (802) and the process moves to step (801). If the remote command does not arrive, it waits until the remote command arrives (801)

As described above, according to the present invention, since the satellite simulator frequently exchanges data between internal processes, a time required for inter-process communication can be remarkably reduced by using a shared memory structure, Are self-functioning according to their respective functions, so the process is not dependent and no synchronization is required when exchanging data. In addition, even if some processes are terminated abnormally, the entire system performs the rest of the operations. By using the shared memory, data can be exchanged at the same speed as a single process structure. There is a great effect that can make simulation possible.

Claims (9)

A shared memory consisting of a satellite attitude and orbit status data area, a meter status data area, a thermal control system status data area, a remote measurement data area, and a remote command data area; Initializes the satellite state data, and starts the attitude and orbit control system simulation process, the power meter simulation process, the thermal control system simulation process, the remote measurement processing process and the remote command processing process, reads the remote measurement data, An operator connection process for terminating each of the processes after the data acquisition, and reading data of the remote command data area, the satellite attitude and orbital state data area and the meter state data area and calculating a new attitude, A posture and orbit control system process for modifying the posture and orbit state data region and the telemetry data region, and a control unit for reading data of the remote command data region, the satellite attitude and orbit state data region and the thermal control system state data region, And a remote metering data process module for modifying the meteorological data area and the telemetry data area after calculating the telemetry values and the data of the normal remote command data area, the satellite attitude and orbit status data area and the meteorological data area, A thermal control system simulation process for calculating a control system status and a remote measurement value and then modifying the thermal control system status data area and the remote measurement data area; and a remote control module for reading the data of the remote measurement data area, To the operator Through the transmit telemetry process and the LAN interface if a new remote command arrives from the satellite operator in real time the simulator structure using a shared memory, characterized in that consisting of the remote command processing process for modifying the remote command data area. Initialization of the satellite state data in the operator connection processing process in which the initial data is inputted from the hard disk of the hardware, and the posture and orbit control system simulation process, the power meter simulation process, the thermal control system simulation process, the remote measurement processing process and the remote command processing process are started, A first step of reading the data of the measurement data area and modifying the remote command data area and terminating the respective processes; and a step of reading the data of the remote command data area, the satellite attitude, the orbit status data, A second step of calculating a new attitude, an orbital state, and a telemetry value in the posture and orbit control system simulation process, and then modifying the satellite attitude and orbit state data area and the telemetry data area; And bin A third step of calculating a new meter state and a remote measurement value in the power meter simulation process that reads the data of the state data area and the thermal control system state data area and then correcting the meter state data area and the remote measurement data area after the calculation of the meter state and the remote measurement value, The new thermal control system status and remote measurement values are calculated in the thermal control system simulation process that reads the data of the data area, the satellite attitude and the orbit status data area and the meter status data area, and then the thermal control system status data area and remote measurement data area are corrected A fifth step of constructing a telemetry frame in a telemetry process process of reading data of the remote command data area and the telemetry data area and then transmitting the telemetry frame to an operator via a LAN interface; From operator From Pacific telecommand a remote command processing process receives the real-time satellite simulation driving method using a shared memory, characterized in that comprising a sixth step of modifying the remote command data area. 3. The system of claim 2, wherein the satellite state and orbit state data region, the meter state data region, the thermal control system state data region, the telemetry data region, and the remote command data region are included in a shared memory. A method of driving a satellite simulation. 3. The method as claimed in claim 2, wherein the first step comprises: initializing the satellite state data by starting the operator access process and reading the initial data from the hard disk; initializing the satellite state data region, The method of claim 1, further comprising: initializing a power meter simulation process, a thermal control system simulation process, a telemetry process process, and a remote command process process; confirming whether there is an operator input after initializing each process; Determining whether the input command is an end command, modifying the remote command data, modifying the remote command data, and confirming whether there is an operator input when the end command is not an end command, And confirmation of the operator input If there is no operator input, displays the remote measurement data on the screen and waits for a predetermined period of time and then checks whether there is an operator input; and if the operator input is a terminate command, And a step of terminating the power meter simulation process, the thermal control system simulation process, the remote measurement process process, and the remote command process process. 3. The method of claim 2, wherein the second step comprises: reading data in a remote command data area when the posture and trajectory control system simulation process is started; and reading actual time and simulation time after reading the remote command data area Comparing the simulation time with a real time after waiting for a predetermined time when the simulation time is ahead of the actual time according to the comparison result; Increasing the simulation time by a predetermined time; reading data of the satellite attitude and orbit state data region after increasing the simulation time; and reading data of the satellite attitude and orbit state data region New satellite attitude and orbit status data and remote Calculating a measured value, modifying the satellite attitude and orbital state data region after calculating the new attitude, orbit state data and telemetry values, modifying the satellite attitude and orbital state data region, Comparing the simulation time with the time; and changing the simulation time by a predetermined time when the actual time is ahead of the simulation time according to the comparison result; and comparing the simulation time with the actual time And modifying the telemetry data area if the telemetry data is ahead of the real time satellite simulator. 3. The method of claim 2, wherein the third step comprises: reading data in the remote command data area when the power meter simulation process is started; comparing the actual time and the simulation time after reading data in the remote command data area; And comparing the simulation time with the actual time after waiting for a predetermined time when the simulation time is ahead of the actual time according to the comparison result; The method comprising: increasing the simulation time by a predetermined amount of time; reading data of the satellite attitude and orbit state data region after increasing the simulation time; reading data of the satellite attitude and orbit state data region, Reading data of the control system status data area, Calculating a new meter state and a remote measurement value after reading the data in the thermal control system state data region; modifying the meter state data region after calculating the new meter state and the remote measurement value; Comparing the actual time and the simulation time after correcting the state data area; and transitioning the simulation time by a predetermined time when the actual time is ahead of the simulation time according to the comparison result, And modifying the telemetry data area when the simulation time is ahead of the actual time according to the simulation result. 3. The method of claim 2, wherein the fourth step comprises: reading data of a remote command data area when the thermal control system simulation process is started; comparing the actual time and the simulation time after reading the data of the remote command data area; Comparing the simulation time with the actual time after waiting for a predetermined time when the simulation time is ahead of the actual time according to the result of the comparison; Increasing the simulation time by a predetermined time, reading data of the satellite attitude and orbit state data region after increasing the simulation time, and reading data of the satellite attitude and orbit state data region The new meter reading the data in the state data area The method of claim 1, further comprising the steps of: calculating a new thermal control system state and a remote measurement value after reading the data of the power system state data region, calculating a new thermal control system state and a remote measurement value, Comparing the actual time with the simulation time after correcting the thermal control system status data area, and when the actual time is ahead of the simulation time according to the comparison result, the simulation time is increased by a predetermined time And modifying the telemetry data region when the simulation time is ahead of the actual time according to the comparison result. The method as claimed in claim 2, wherein the fifth step comprises: reading data of the remote command data area by starting the remote measurement processing process; reading data of the remote command data area after reading the data of the remote command data area; Generating a telemetry frame by reconstructing the telemetry data and the telemetry data; transmitting the telemetry frame to the operator via the LAN interface; waiting for a predetermined time; And the step of shifting to the reading step. 3. The method as claimed in claim 2, wherein the step (c) further comprises: waiting for a remote command from the operator to arrive via the LAN, when the remote command processing process is started; And a step of waiting for a remote command to arrive when the remote command is not received from the operator. The method according to claim 1, Driving method.