Ground Station Simulator

The system-level testing of the framework consists in having an application instantiated from the framework running in either open-loop mode (system-level testing in the desktop environment) or closed-loop mode (system-level testing in the embedded environment). In both cases, the instantiated application will be sending telemetry data and will need to receive telecommands data. For this purpose, a simple ground station simulator (GSS) was developed. The GSS is tailored to the needs of the SMM prototype application. It can display and store the telemetry data that is generated by this application and it can send telecommands to this application. 

Telemetry Data Display

Telemetry data are displayed in a dedicated window. The window has fields to show: the values of the data pool variables, the current on-board time and the current operational mode of the mission mode manager. Additionally, it displays the events reported in telemetry. A subwindow is used to send telecommands.

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Telemetry Data Storage

Telemetry data are stored in a file in the same format in which they are received from the SMM application. The file is called "RawTmData.txt" and can be found in the project directory. Since the raw telemetry data are sent in a format that is not easily readable, the telemetry data are on-line decoded and analyzed. The result of such procedure is stored in a file. The file is called "FormatedTmData.txt" and placed in the same directory as the file with raw data.

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Telecommand Sending

Telecommand can be sent from a subwindow in the telemetry display window. Telecommands are sent as sequences of integers (see the telecommand approach for the prototype application) packaged as a string. A pull-down menu lets the user select the telecommand type and displays hints as to the number and function of the integers that make up the telecommand. The telecommand parameters are filled in an editable text field and are sent to SMM application when a button with the label "Send" is pressed (see GUI).

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Package Structure

The software for the ground station simulator is stored in a dedicated package called GroundStationSimulator. This package can be downloaded together with the rest of the framework software. 

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Graphical User Interface

How to work with the GUI?

In order to run the ground station application set the GsGUI class as the main class. Run the program. From the main menu choose "Setting -> IP address" item and set the IP address of the target (a computer where is running SMM application). In the next step click on the "Start" item hidden under the menu option "Simulator". The ground station simulator will establish a connection and start the SMM application. If you wish to stop and exit the ground station simulator choose from the main menu "Simulator -> Stop", "Simulator -> Exit". 

The telemetry window displays decoded telemetry data. The system mode, system time and telemetry messages visualization components are updated each second whereas new values of the measurement, reference, control action, and control error are coming every two seconds.

In the telecommand window telecommands can be configured and sent to SMM application. Once there is a requirement to send a telecommand, then in the first step the pull-down menu should be explored and an appropriate telecommand chosen. In the second step correct parameters filled in the text field "Parameters", and finally the telecommand is sent by pressing the button with the label "Send". 

The GUI interface is shown in the figure below. Its main fields are:

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Last updated on Apr. 29-th 2002 by Alessandro Pasetti