How To Add Components

1. Overview

• In the How To Make New Simulation Scenario tutorial, we have made an s2e-user directory for our simulation scenario.
• This tutorial explains how to add components to your scenario.
• A similar procedure is available for other components in the s2e-core.
  • Please see the components listed in the components directory.
• The supported version of this document
  • Please confirm that the version of the documents and s2e-core is compatible.

2. Add a Gyro sensor

• This chapter explains how to add a gyro sensor component to your s2e-user simulation case step by step.
• Users can find the sample code of this section in s2e-user-example/sample/how-to-add-components.

1. Open & edit user_components.hpp

   • Add the following descriptions at the one line below of #include <components/real/cdh/on_board_computer.hpp>

     #include <components/real/aocs/initialize_gyro_sensor.hpp>
     

   • Add the following descriptions at the one line below of OnBoardComputer *obc_; //!< Onboard Computer

     GyroSensor *gyro_sensor_;  //!< Gyro sensor
     

2. Open and edit user_components.cpp

   • Edit the constructor function as follows to create an instance of the GyroSensor class at the one line below of obc_ = new OnBoardComputer(clock_generator);.

     // Common
     IniAccess iniAccess = IniAccess(configuration_->spacecraft_file_list_[spacecraft_id]);
     const double compo_step_sec = global_environment_->GetSimulationTime().GetComponentStepTime_s();
     
     // Initialize of GYRO class
     std::string file_name = iniAccess.ReadString("COMPONENT_FILES", "gyro_file");
     configuration_->main_logger_->CopyFileToLogDirectory(file_name);
     gyro_sensor_ = new GyroSensor(InitGyroSensor(clock_generator, 1, file_name, compo_step_sec, dynamics));
     

   • Add the following descriptions at the one line up of delete obc_; in the destructor.

     delete gyro_sensor_;
     

   • Edit the LogSetup function as follows to register log output

     void UserComponents::LogSetup(Logger &logger) { logger.AddLogList(gyro_sensor_); }
     

3. Open user_satellite.ini and edit initial_angular_velocity_b_rad_s to add initial angular velocity.

   • Users can select any value.

4. Add the following descriptions at the bottom line of [COMPONENT_FILES] to set the initialize file for the gyro sensor.

   gyro_file = ../../data/initialize_files/components/gyro_sensor_xxx.ini
   

5. Build the s2e-user and execute it

6. Check the log output file to find gyro_sensor1_measured_angular_velocity_c, the gyro sensor's output angular velocity value in the component frame.

   • Since the default initializing file is described as that the sensor has no noise, the value of gyro_sensor1_measured_angular_velocity_c and spacecraft_angular_velocity_b is completely the same.

7. Edit the data/initialize_files/components/gyro_sensor_xxx.ini file to add several noises, and rerun the s2e-user

8. Check the log output file to find gyro_sensor1_measured_angular_velocity_c. Now the sensor output has several errors you set in the initialize file like the following figure.

   • We edited the file as constant_bias_c_rad_s(0) = 0.001 and normal_random_standard_deviation_c_rad_s(0) = 0.001 to get the following figure.
   

3. Add another Gyro sensor

• You can add multiple components in your s2e-user simulation case similar to the above sequence.

1. Open user_components.hpp

2. Add the following descriptions at the one line below of GyroSensor *gyro_sensor_;

   GyroSensor *gyro_sensor_2_;  //!< Gyro sensor 2
   

3. Open user_components.cpp

4. Edit the constructor function to add the following description to create the second instance of the GYRO class

   file_name = iniAccess.ReadString("COMPONENT_FILES", "gyro_file_2");
   configuration_->main_logger_->CopyFileToLogDirectory(file_name);
   gyro_sensor_2_ = new GyroSensor(InitGyroSensor(clock_generator, 2, file_name, compo_step_sec, dynamics));
   

5. Add the following descriptions at the one line below of delete gyro_; in the destructor

   delete gyro_sensor_2_;
   

6. Edit the LogSetUp function as follows to register log output

   void UserComponents::LogSetup(Logger &logger) {
     logger.AddLogList(gyro_sensor_);
     logger.AddLogList(gyro_sensor_2_);
   }
   

7. Open user_satellite.ini

8. Add the following descriptions at the bottom line of [COMPONENT_FILES] to set the initialize file for the gyro sensor

   gyro_file_2 = ../../data/initialize_files/components/gyro_sensor_yyy.ini
   

9. Copy the data/initialize_files/components/gyro_sensor_xxx.ini file and rename it as gyro_sensor_yyy.ini

10. Edit gyro_sensor_yyy.ini to custom the noise performance of the second gyro sensor

    • Edit sensor ID like [GYRO_SENSOR_1] to [GYRO_SENSOR_2]
    • Edit sensor ID like [SENSOR_BASE_GYRO_SENSOR_1] to [SENSOR_BASE_GYRO_SENSOR_2]

11. Build the s2e-user and execute it

12. Check the log output file to find gyro_sensor2_measured_angular_velocity_c, the second gyro sensor's output angular velocity value in the component frame.