added new mass-spring-damper sim and graphics client (#555)

* added new mass-spring-damper sim and graphics client

* changed math model image for README.md

* updated math model image for README.md

trick_sims/SIM_msd/Modified_data/realtime.py

@@ -0,0 +1,7 @@
+trick.frame_log_on()
+trick.real_time_enable()
+trick.exec_set_software_frame(0.1)
+trick.itimer_enable()
+trick.exec_set_enable_freeze(True)
+trick.exec_set_freeze_command(True)
+trick.sim_control_panel_set_enabled(True)

trick_sims/SIM_msd/README.md

@@ -0,0 +1,84 @@
+# SIM_MSD
+
+SIM\_MSD is a simulator for a mass-spring-damper system.
+
+![Picture of MSD](./images/MSD0.png)
+
+ The system is described by the equation _mẍ_ + _bẋ_ + _kx_ = _F_, where:
+
+ _m_ is the mass of an object.
+
+ _x_ is the position of the mass.
+
+ _b_ is the damping coefficient.
+
+ _k_ is the spring coefficient.
+
+ _F_ is an external force applied to the mass.
+
+---
+### Building the Simulation
+
+In the SIM_MSD directory, execute **trick-CP** to build the simulation executable. When it's complete, you should see:
+
+```
+=== Simulation make complete ===
+```
+
+Now **cd** into models/Graphics/ and type **make**. This builds the display client for the simulation.
+
+### Running the Simulation
+In the SIM_MSD directory:
+
+```
+% ./S_main_*.exe RUN_test/input.py
+```
+
+The following windows should appear:
+
+![Picture of MSD](./images/MSD2.png)
+
+![Picture of Control](./images/MSD3.png)
+
+### Controlling the Simulation
+Click **Start** to begin the simulation.
+
+Click **Reset** to freeze the simulation and reset the position and velocity to
+their initial conditions.
+
+Change **Position** and **Velocity** to adjust the initial conditions for those
+attributes.
+
+Change **Mass**, **Spring Coefficient**, **Damping Coefficient**, and **Applied
+Force** to adjust initial conditions _**and**_ also update the sim in real-time.
+
+
+
+
+
+
+---
+The following inputs can be set in any of the RUN_*/input.py files to change
+the inputs on startup
+### Inputs
+
+Variable    | Type      | Units | Default Value
+----------  |-----------|-------|--------------
+dyn.msd.x_0 | double    | m     | 5.0
+dyn.msd.v_0 | double    | m/s   | 0.0
+dyn.msd.b   | double    | N.s/m | 0.5
+dyn.msd.k   | double    |  N/m  | 2.0
+dyn.msd.F   | double    | N     | 5.0
+dyn.msd.m   | double    | kg    | 1.0
+
+---
+Some sample input.py files have been created to demonstrate different
+mass-spring-damper conditions
+### Samples
+
+Path                    |Type
+------------------------|----------------------------------------------
+RUN_underdamp/input.py  |Underdamped Harmonic Oscillator
+RUN_critdamp/input.py   |Critically Damped Harmonic Oscillator
+RUN_overdamp/input.py   |Overdamped Harmonic Oscillator
+RUN_nodamp/input.py     | Simple Harmonic Oscillator (No Damping Force)

trick_sims/SIM_msd/RUN_critdamp/input.py

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+dyn_integloop.getIntegrator(trick.Runge_Kutta_4, 4)
+execfile("Modified_data/realtime.py")
+
+dyn.msd.b = 2*(2**(0.5))
+
+#==========================================
+# Start the display VarServer Client
+#==========================================
+varServerPort = trick.var_server_get_port();
+MsdGui_path = "models/graphics/dist/MsdGui.jar"
+
+if (os.path.isfile(MsdGui_path)) :
+    MsdGui_cmd = "java -jar " \
+                  + MsdGui_path \
+                  + " " + str(varServerPort) + " &" ;
+    print(MsdGui_cmd)
+    os.system( MsdGui_cmd);
+else :
+    print('==================================================================================')
+    print('MsdGui needs to be built. Please \"cd\" into models/Graphics and type \"make\".')
+    print('==================================================================================')
+
+trick.stop(300.0)

trick_sims/SIM_msd/RUN_nodamp/input.py

@@ -0,0 +1,23 @@
+dyn_integloop.getIntegrator(trick.Runge_Kutta_4, 4)
+execfile("Modified_data/realtime.py")
+
+dyn.msd.b = 0
+
+#==========================================
+# Start the display VarServer Client
+#==========================================
+varServerPort = trick.var_server_get_port();
+MsdGui_path = "models/graphics/dist/MsdGui.jar"
+
+if (os.path.isfile(MsdGui_path)) :
+    MsdGui_cmd = "java -jar " \
+                  + MsdGui_path \
+                  + " " + str(varServerPort) + " &" ;
+    print(MsdGui_cmd)
+    os.system( MsdGui_cmd);
+else :
+    print('==================================================================================')
+    print('MsdGui needs to be built. Please \"cd\" into models/Graphics and type \"make\".')
+    print('==================================================================================')
+
+trick.stop(300.0)

trick_sims/SIM_msd/RUN_overdamp/input.py

@@ -0,0 +1,23 @@
+dyn_integloop.getIntegrator(trick.Runge_Kutta_4, 4)
+execfile("Modified_data/realtime.py")
+
+dyn.msd.b = 4*(2**(0.5)) - 1/2
+
+#==========================================
+# Start the display VarServer Client
+#==========================================
+varServerPort = trick.var_server_get_port();
+MsdGui_path = "models/graphics/dist/MsdGui.jar"
+
+if (os.path.isfile(MsdGui_path)) :
+    MsdGui_cmd = "java -jar " \
+                  + MsdGui_path \
+                  + " " + str(varServerPort) + " &" ;
+    print(MsdGui_cmd)
+    os.system( MsdGui_cmd);
+else :
+    print('==================================================================================')
+    print('MsdGui needs to be built. Please \"cd\" into models/Graphics and type \"make\".')
+    print('==================================================================================')
+
+trick.stop(300.0)

trick_sims/SIM_msd/RUN_test/input.py

@@ -0,0 +1,21 @@
+dyn_integloop.getIntegrator(trick.Runge_Kutta_4, 4)
+execfile("Modified_data/realtime.py")
+
+#==========================================
+# Start the display VarServer Client
+#==========================================
+varServerPort = trick.var_server_get_port();
+MsdGui_path = "models/graphics/dist/MsdGui.jar"
+
+if (os.path.isfile(MsdGui_path)) :
+    MsdGui_cmd = "java -jar " \
+                  + MsdGui_path \
+                  + " " + str(varServerPort) + " &" ;
+    print(MsdGui_cmd)
+    os.system( MsdGui_cmd);
+else :
+    print('==================================================================================')
+    print('MsdGui needs to be built. Please \"cd\" into models/Graphics and type \"make\".')
+    print('==================================================================================')
+
+trick.stop(300.0)

trick_sims/SIM_msd/RUN_underdamp/input.py

@@ -0,0 +1,23 @@
+dyn_integloop.getIntegrator(trick.Runge_Kutta_4, 4)
+execfile("Modified_data/realtime.py")
+
+dyn.msd.b = 0.5
+
+#==========================================
+# Start the display VarServer Client
+#==========================================
+varServerPort = trick.var_server_get_port();
+MsdGui_path = "models/graphics/dist/MsdGui.jar"
+
+if (os.path.isfile(MsdGui_path)) :
+    MsdGui_cmd = "java -jar " \
+                  + MsdGui_path \
+                  + " " + str(varServerPort) + " &" ;
+    print(MsdGui_cmd)
+    os.system( MsdGui_cmd);
+else :
+    print('==================================================================================')
+    print('MsdGui needs to be built. Please \"cd\" into models/Graphics and type \"make\".')
+    print('==================================================================================')
+
+trick.stop(300.0)

trick_sims/SIM_msd/S_define

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+/************************TRICK HEADER*************************
+PURPOSE:
+    (This S_define works with the RUN_numeric input file)
+LIBRARY DEPENDENCIES:
+    (
+      (msd/src/msd_init.cpp)
+      (msd/src/msd_numeric.cpp)
+      (msd/src/msd_shutdown.cpp)
+      (msd/src/msd.cpp)
+      (msd/src/msd_deriv.cpp)
+      (msd/src/msd_integ.cpp)
+    )
+*************************************************************/
+
+#include "sim_objects/default_trick_sys.sm"
+##include "msd/include/msd_numeric.hh"
+
+
+class MSDSimObject : public Trick::SimObject {
+
+    public:
+        MSD msd;
+
+        MSDSimObject() {
+            ("default_data") msd_default_data( msd ) ;
+            ("initialization") msd_init( msd ) ;
+            ("derivative") msd.state_deriv();
+            ("integration") trick_ret= msd.state_integ();
+        }
+} ;
+
+MSDSimObject dyn ;
+IntegLoop dyn_integloop (0.01) dyn ;

trick_sims/SIM_msd/S_overrides.mk

@@ -0,0 +1,2 @@
+TRICK_CFLAGS += -Imodels
+TRICK_CXXFLAGS += -Imodels

trick_sims/SIM_msd/models/graphics/MSD/src/MsdController.java

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+/*
+ * Trick
+ * 2018 (c) National Aeronautics and Space Administration (NASA)
+ * Programmers: Scott P. Fennell
+ */
+
+
+
+import javax.swing.*;
+import javax.swing.JTextField;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+public class MsdController extends JFrame {
+    JTextField positionTextField;
+    JTextField velocityTextField;
+    JTextField springTextField;
+    JTextField dampingTextField;
+    JTextField forceTextField;
+    JTextField massTextField;
+
+    ButtonPanel buttonPanel;
+    JPanel positionPanel;
+    JPanel labelPanel;
+
+    public void armResetCommand() {
+        buttonPanel.armResetCommand();
+    }
+
+    public void armStartCommand() {
+        buttonPanel.armStartCommand();
+    }
+
+    public boolean getResetCommand() {
+        return buttonPanel.getResetCommand();
+    }
+
+    public boolean getStartCommand() {
+        return buttonPanel.getStartCommand();
+    }
+
+    public MsdController(MsdDisplay display){
+        setTitle("Mass-Spring-Damper Control");
+        setLayout(new GridLayout(1, 2));
+
+        buttonPanel = new ButtonPanel(display);
+        positionPanel = new JPanel();
+        labelPanel = new JPanel();
+        labelPanel.setAlignmentX(Component.RIGHT_ALIGNMENT);
+
+        positionPanel.setLayout(new GridLayout(13, 1));
+        labelPanel.setLayout(new GridLayout(13, 1));
+        JPanel framePanel = new JPanel();
+        GridLayout layout = new GridLayout(1, 3);
+        framePanel.setLayout(layout);
+
+        positionTextField = new JTextField(2);
+        velocityTextField = new JTextField(2);
+        massTextField = new JTextField(2);
+        forceTextField = new JTextField(2);
+        springTextField = new JTextField(2);
+        dampingTextField = new JTextField(2);
+
+
+
+
+
+
+        labelPanel.add(new JLabel());
+        labelPanel.add(new JLabel("Position: "));
+        labelPanel.add(new JLabel());
+        labelPanel.add(new JLabel("Velocity: "));
+        labelPanel.add(new JLabel());
+        labelPanel.add(new JLabel("Mass: "));
+        labelPanel.add(new JLabel());
+        labelPanel.add(new JLabel("Spring Coefficient: "));
+        labelPanel.add(new JLabel());
+        labelPanel.add(new JLabel("Damping Coefficient: "));
+        labelPanel.add(new JLabel());
+        labelPanel.add(new JLabel("Applied Force: "));
+        labelPanel.add(new JLabel());
+
+        positionPanel.add(new JLabel());
+        positionPanel.add(positionTextField);
+        positionPanel.add(new JLabel());
+        positionPanel.add(velocityTextField);
+        positionPanel.add(new JLabel());
+        positionPanel.add(massTextField);
+        positionPanel.add(new JLabel());
+        positionPanel.add(springTextField);
+        positionPanel.add(new JLabel());
+        positionPanel.add(dampingTextField);
+        positionPanel.add(new JLabel());
+        positionPanel.add(forceTextField);
+        positionPanel.add(new JLabel());
+
+
+        for(Component L : labelPanel.getComponents()){
+            if(L instanceof JLabel){
+                ((JLabel)L).setHorizontalAlignment(JLabel.RIGHT);
+            }
+        }
+        framePanel.add(buttonPanel);
+        framePanel.add(labelPanel);
+        framePanel.add(positionPanel);
+
+        add(framePanel);
+        positionPanel.setSize(positionPanel.getLayout().preferredLayoutSize(positionPanel));
+        buttonPanel.setSize(buttonPanel.getPreferredSize());
+        setSize(getPreferredSize());
+        setLocationByPlatform(true);
+        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+
+    }
+
+    class ButtonPanel extends JPanel implements ActionListener {
+
+        private MsdDisplay msdDisplay;
+        private boolean startCommand;
+        private boolean resetCommand;
+        private JButton startButton, resetButton, zoomOutButton, zoomInButton;
+
+
+        public ButtonPanel(MsdDisplay cd) {
+            msdDisplay = cd;
+            startCommand = false;
+            resetCommand = false;
+            setLayout(new GridLayout(4,1 ));
+
+            startButton = new JButton("Start");
+            startButton.addActionListener(this);
+            startButton.setActionCommand("start");
+            startButton.setToolTipText("Start MSD");
+            add(startButton);
+
+            resetButton = new JButton("Reset");
+            resetButton.addActionListener(this);
+            resetButton.setActionCommand("reset");
+            resetButton.setToolTipText("Reset MSD");
+            add(resetButton);
+
+            zoomOutButton = new JButton("\u25b2");
+            zoomOutButton.addActionListener(this);
+            zoomOutButton.setActionCommand("zoomout");
+            zoomOutButton.setToolTipText("Zoom in");
+            add(zoomOutButton);
+
+            zoomInButton = new JButton("\u25bc");
+            zoomInButton.addActionListener(this);
+            zoomInButton.setActionCommand("zoomin");
+            zoomInButton.setToolTipText("Zoom Out");
+            add(zoomInButton);
+
+        }
+
+        public void actionPerformed(ActionEvent e) {
+            String s = e.getActionCommand();
+            switch (s) {
+                case "start":
+                    startCommand = true;
+                    break;
+                case "reset":
+                    resetCommand = true;
+
+                    break;
+                case "zoomin":
+                    msdDisplay.setScale(msdDisplay.getScale() / 2);
+                    break;
+                case "zoomout":
+                    msdDisplay.setScale(msdDisplay.getScale() * 2);
+                    break;
+                default:
+                    System.out.println("Unknown Action Command:" + s);
+                    break;
+            }
+        }
+
+        public void armResetCommand() {
+            resetCommand = false;
+            startButton.setForeground(Color.red);
+        }
+
+        public void armStartCommand() {
+            startCommand = false;
+            startButton.setForeground(Color.gray);
+        }
+
+        public boolean getResetCommand() {
+            return resetCommand;
+        }
+
+        public boolean getStartCommand() {
+            return startCommand;
+        }
+
+    } // class ButtonPanel
+
+
+}

trick_sims/SIM_msd/models/graphics/MSD/src/MsdDisplay.java

@@ -0,0 +1,50 @@
+/*
+ * Trick
+ * 2018 (c) National Aeronautics and Space Administration (NASA)
+ * Programmers: Scott P. Fennell
+ */
+
+
+import javax.swing.*;
+
+
+public class MsdDisplay extends JFrame {
+    MsdView msdView;
+
+
+
+    public void setPosition(double value) {
+        msdView.setPosition(value);
+    }
+
+    public void setVelocity(double value) {
+        msdView.setVelocity(value);
+    }
+
+    public void setScale(int value) {
+        msdView.setScale(value);
+    }
+
+    public int getScale() {
+        return msdView.getScale();
+    }
+
+    public void drawMsdView() {
+        msdView.repaint();
+    }
+
+
+
+    public MsdDisplay(MsdView arena) {
+        setTitle("Mass-Spring-Damper");
+        msdView = arena;
+        add(msdView);
+
+
+        setSize(800, 500);
+        setLocationByPlatform(true);
+
+        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+    }
+
+}

trick_sims/SIM_msd/models/graphics/MSD/src/MsdGui.java

@@ -0,0 +1,218 @@
+/*
+ * Trick
+ * 2018 (c) National Aeronautics and Space Administration (NASA)
+ * Programmers: Scott P. Fennell
+ */
+
+
+import java.awt.*;
+import java.io.*;
+import java.net.Socket;
+
+public class MsdGui {
+
+    static BufferedReader in;
+    static DataOutputStream out;
+
+    public static void connectToServer(String host, int port) throws IOException {
+        Socket socket = new Socket(host, port);
+        in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
+        out = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream()));
+    }
+
+    public static void main(String[] args) throws IOException {
+
+        String host = "localHost";
+        int port = 0;
+
+        // ==========================================================
+        // Handle program arguments.
+        // ==========================================================
+        int ii = 0;
+        while (ii < args.length) {
+            switch (args[ii]) {
+                case "-help":
+                case "--help": {
+                    MsdUtils.printHelpText();
+                    System.exit(0);
+                }
+                break;
+                default: {
+                    port = (Integer.parseInt(args[ii]));
+                }
+                break;
+            }
+            ++ii;
+        }
+
+        if (port == 0) {
+            System.out.println("No variable server port specified.");
+            MsdUtils.printHelpText();
+            System.exit(0);
+        }
+
+        boolean go = true;
+        double dt = 0.01; // Time between updates (seconds).
+        double pos = 0.0;
+        double vel = 0.0;
+        boolean resetCommand;
+        boolean startCommand;
+
+
+        int simMode = 0;
+
+
+        int mapScale = 32; // pixels per meter.
+
+        MsdView msdView = new MsdView(mapScale);
+        MsdDisplay display = new MsdDisplay(msdView);
+        MsdController controller = new MsdController(display);
+        display.setVisible(true);
+        display.drawMsdView();
+        controller.setVisible(true);
+        controller.setLocation(new Point((int)display.getLocationOnScreen().getX() + display.getWidth(), (int)display.getLocationOnScreen().getY()));
+        controller.setSize(controller.getWidth() + 10, display.getHeight());
+
+        // Connect to the Trick simulation's variable server
+        System.out.println("Connecting to: " + host + ":" + port);
+        connectToServer(host, port);
+
+        out.writeBytes("trick.var_set_client_tag(\"MsdGui\") \n");
+        out.flush();
+
+        // Have the Variable Server send us the simulation mode ONCE.
+        out.writeBytes("trick.var_add(\"trick_sys.sched.mode\")\n" +
+                "trick.var_add(\"dyn.msd.x_0\")\n" +
+                "trick.var_add(\"dyn.msd.v_0\")\n" +
+                "trick.var_add(\"dyn.msd.m\")\n" +
+                "trick.var_add(\"dyn.msd.b\")\n" +
+                "trick.var_add(\"dyn.msd.k\")\n" +
+                "trick.var_add(\"dyn.msd.F\")\n" +
+                "trick.var_send() \n" +
+                "trick.var_clear() \n");
+        out.flush();
+
+        // Read the response and extract the simulation mode. Initialize text fields with initial values.
+        try {
+            String line;
+            String field[];
+            line = in.readLine();
+            field = line.split("\t");
+            simMode = Integer.parseInt(field[1]);
+            controller.positionTextField.setText(String.format("%.2f", new Double(field[2])));
+            controller.velocityTextField.setText(String.format("%.2f", new Double(field[3])));
+            controller.massTextField.setText(String.format("%.2f", new Double(field[4])));
+            controller.dampingTextField.setText(String.format("%.2f", new Double(field[5])));
+            controller.springTextField.setText(String.format("%.2f", new Double(field[6])));
+            controller.forceTextField.setText(String.format("%.2f", new Double(field[7])));
+        } catch (IOException | NullPointerException e) {
+            go = false;
+        }
+
+        // If we're in FREEZE, make ready to start.
+        if (simMode == TrickSimMode.FREEZE) {
+            controller.armResetCommand();
+        }
+
+        // Configure the Variable Server to cyclically send us the following variables.
+        // Tell the variable server:
+        //  1) We want the values of the following variables:
+        out.writeBytes("trick.var_pause() \n" +
+                "trick.var_add(\"dyn.msd.x\")\n" +
+                "trick.var_add(\"dyn.msd.v\")\n" +
+                "trick.var_add(\"trick_sys.sched.mode\")\n" +
+                //  2) We want the responses in ASCII:
+                "trick.var_ascii() \n" +
+                /*  3) We want debug information:
+                "trick.var_debug(1) \n" +
+                */
+                //  4) We want values to be updated at the specified rate:
+                String.format("trick.var_cycle(%.3f)\n", dt) +
+                //  5) Start sending values as specified.
+                "trick.var_unpause() \n");
+        out.flush();
+
+        while (go) {
+
+            // Receive and parse periodic data response from the variable server.
+            try {
+                String line;
+                String field[];
+                line = in.readLine();
+                field = line.split("\t");
+                pos = Double.parseDouble(field[1]);
+                vel = Double.parseDouble(field[2]);
+                simMode = Integer.parseInt(field[3]);
+            } catch (IOException | NullPointerException e) {
+                go = false;
+            }
+            // Get inputs from the GUI.
+            resetCommand = controller.getResetCommand();
+            startCommand = controller.getStartCommand();
+
+            if (simMode == TrickSimMode.FREEZE) {
+
+                controller.armResetCommand();
+                resetCommand = false;
+                if (!controller.positionTextField.getText().isEmpty() && new Double(controller.positionTextField.getText()) >= 0.0) {
+                    display.msdView.hideWall = false;
+                }
+                if (!(controller.positionTextField.getText().isEmpty() ||
+                        controller.velocityTextField.getText().isEmpty() ||
+                        controller.springTextField.getText().isEmpty() ||
+                        controller.dampingTextField.getText().isEmpty() ||
+                        controller.massTextField.getText().isEmpty() ||
+                        controller.forceTextField.getText().isEmpty())) {
+
+                    out.writeBytes(
+                            "dyn.msd.x_0 = " + controller.positionTextField.getText() + ";\n" +
+                                    "dyn.msd.v_0 = " + controller.velocityTextField.getText() + ";\n" +
+                                    "dyn.msd.k = " + controller.springTextField.getText() + ";\n" +
+                                    "dyn.msd.b = " + controller.dampingTextField.getText() + ";\n" +
+                                    "dyn.msd.m = " + controller.massTextField.getText() + ";\n" +
+                                    "dyn.msd.F = " + controller.forceTextField.getText() + ";\n");
+                    out.writeBytes("dyn.msd.x = dyn.msd.x_0 ;\n");
+                    out.writeBytes("dyn.msd.v = dyn.msd.v_0 ;\n");
+                }
+
+                if (startCommand) {
+                    out.writeBytes(String.format("trick.exec_run();\n"));
+
+                    out.flush();
+                }
+                if (resetCommand) {
+                    out.writeBytes(String.format("trick.exec_freeze() ;\n"));
+                    continue;
+                }
+                out.flush();
+
+            } else if (simMode == TrickSimMode.RUN) {
+                controller.armStartCommand();
+                startCommand = false;
+                if (resetCommand) {
+                    out.writeBytes(String.format("trick.exec_freeze() ;\n"));
+                    out.flush();
+                }
+                if (!(controller.springTextField.getText().isEmpty() ||
+                        controller.dampingTextField.getText().isEmpty() ||
+                        controller.massTextField.getText().isEmpty() ||
+                        controller.forceTextField.getText().isEmpty())) {
+                    out.writeBytes(
+                            "dyn.msd.k = " + controller.springTextField.getText() + ";\n" +
+                                    "dyn.msd.b = " + controller.dampingTextField.getText() + ";\n" +
+                                    "dyn.msd.m = " + controller.massTextField.getText() + ";\n" +
+                                    "dyn.msd.F = " + controller.forceTextField.getText() + ";\n");
+                }
+            }
+
+            // Update the display data.
+            display.setPosition(pos);
+            display.setVelocity(vel);
+
+            //  Update the scene.
+            display.drawMsdView();
+
+        } // while
+
+    }
+}

trick_sims/SIM_msd/models/graphics/MSD/src/MsdUtils.java

@@ -0,0 +1,24 @@
+/*
+ * Trick
+ * 2018 (c) National Aeronautics and Space Administration (NASA)
+ * Programmers: Scott P. Fennell
+ */
+
+
+
+public class MsdUtils {
+
+    public static void  printHelpText() {
+        System.out.println(
+                "----------------------------------------------------------------------\n"
+                        + "usage: java jar CannonDisplay.jar <port-number>\n"
+                        + "----------------------------------------------------------------------\n"
+        );
+    }
+}
+
+class TrickSimMode {
+    public static final int INIT = 0;
+    public static final int FREEZE = 1;
+    public static final int RUN = 5;
+}

trick_sims/SIM_msd/models/graphics/MSD/src/MsdView.java

@@ -0,0 +1,183 @@
+/*
+ * Trick
+ * 2018 (c) National Aeronautics and Space Administration (NASA)
+ * Programmers: Scott P. Fennell
+ */
+
+
+
+import javax.swing.*;
+import java.awt.*;
+
+class MsdView extends JPanel {
+
+    private int scale;
+    private Color massColor;
+    private Color backgroundColor;
+    private Color wallColor;
+    private Color springColor;
+    private Double position;
+    private Double velocity;
+    private Double massRadius;
+    boolean hideWall = false;
+
+    // Origin of world coordinates in jpanel coordinates.
+    private int worldOriginX;
+    private int worldOriginY;
+
+
+    /**
+     * Class constructor.
+     */
+    public MsdView(int mapScale) {
+
+        setScale(mapScale);
+
+        backgroundColor = new Color(200, 200, 255);
+        springColor = new Color(150, 150, 100);
+        massColor = new Color(10, 10, 10);
+        wallColor = new Color(120, 118, 118);
+        springColor = Color.BLUE;
+        massRadius = 0.75;
+        position = 0.0;
+        velocity = 0.0;
+    }
+
+    /**
+     * @param value angle in degrees
+     */
+    public void setPosition(double value) {
+        position = value;
+    }
+
+    public void setVelocity(double value) {
+        velocity = value;
+    }
+
+    public void setScale(int mapScale) {
+        if (mapScale < 4) {
+            scale = 4;
+        } else if (mapScale > 128) {
+            scale = 128;
+        } else {
+            scale = mapScale;
+        }
+        repaint();
+    }
+
+    public int getScale() {
+        return scale;
+    }
+
+    public void drawCenteredCircle(Graphics2D g, int x, int y, int r) {
+        x = x - (r / 2);
+        y = y - (r / 2);
+        g.fillOval(x, y, r, r);
+    }
+
+    private void doDrawing(Graphics g) {
+        Graphics2D g2d = (Graphics2D) g;
+
+        RenderingHints rh = new RenderingHints(
+                RenderingHints.KEY_ANTIALIASING,
+                RenderingHints.VALUE_ANTIALIAS_ON);
+
+        rh.put(RenderingHints.KEY_RENDERING,
+                RenderingHints.VALUE_RENDER_QUALITY);
+
+        int ii, jj;
+        int width = getWidth();
+        int height = getHeight();
+
+
+        worldOriginX = (width / 3);
+        worldOriginY = (height / 2);
+
+        while (worldOriginX + scale * position > width) {
+            scale = scale / 2;
+        }
+
+        // Draw Sky
+        g2d.setPaint(backgroundColor);
+        g2d.fillRect(0, 0, width, worldOriginY);
+
+        //  Draw mass
+        g2d.setPaint(massColor);
+        int bx = (int) (worldOriginX + scale * position);
+        int by = (int) (worldOriginY);
+        drawCenteredCircle(g2d, bx, by, (int) (scale * massRadius));
+
+        // Draw spring
+        double springPosition;
+        // reflect spring visual over origin correctly
+        if(position < massRadius/2 && position > -massRadius/2){
+           springPosition = 0.0;
+        } else if(position < 0){
+            springPosition = position + massRadius/2;
+        } else{
+            springPosition = position - massRadius/2;
+        }
+        int SCALEFACTOR = 200;
+        int cycles = 5;
+        int points = SCALEFACTOR * cycles * 2;
+        double[] sines = new double[points];
+        for (int i = 0; i < points; i++) {
+            double radians = (Math.PI / SCALEFACTOR) * i;
+            sines[i] = Math.sin(radians);
+        }
+        int maxWidth = (int) (scale * (springPosition /*- massRadius / 2*/));
+        double hstep = (double) maxWidth / (double) points;
+        int maxHeight = (int) (scale);
+        int[] pts = new int[points];
+        for (int i = 0; i < points; i++) {
+            pts[i] = (int) (sines[i] * maxHeight / 2 * .95 + maxHeight / 2);
+        }
+        g2d.setColor(springColor);
+        for (int i = 1; i < points; i++) {
+            int x1 = (int) ((i - 1) * hstep);
+            int x2 = (int) (i * hstep);
+            int y1 = pts[i - 1];
+            int y2 = pts[i];
+            g2d.drawLine(x1 + worldOriginX, y1 + height / 2 - scale / 2, x2 + worldOriginX, y2 + height / 2 - scale / 2);
+
+        }
+
+        //Draw wall
+        if (!hideWall && position >= 0) {
+            g2d.setPaint(wallColor);
+            g2d.fillRect(0, 0, worldOriginX, height);
+        } else {
+            hideWall = true;
+        }
+
+
+        // Draw range markers.
+        int tickRange = 50;
+        if (scale >= 8) tickRange = 20;
+        if (scale >= 16) tickRange = 10;
+        if (scale >= 32) tickRange = 5;
+        if (scale >= 64) tickRange = 1;
+
+        int lower = ((int) ((-worldOriginX) / (scale * tickRange)) + 1) * tickRange;
+        int upper = ((int) ((width - worldOriginX) / (scale * tickRange)) + 1) * tickRange;
+
+        g2d.setPaint(Color.BLACK);
+
+        for (ii = lower; ii < upper; ii += tickRange) {
+            int mx = (int) (worldOriginX + scale * ii);
+            g2d.drawLine(mx, worldOriginY, mx, worldOriginY + 20);
+            g2d.drawString(String.format("%d", ii), mx, worldOriginY + 15);
+        }
+
+        g2d.drawString(String.format("SCALE: %d pixels/meter", scale), 20, 20);
+        g2d.drawString(String.format("  Position (m): %.2f", position), 20, 80);
+        g2d.drawString(String.format("Velocity (m/s): %.2f", velocity), 20, 120);
+
+    }
+
+    @Override
+    public void paintComponent(Graphics g) {
+        super.paintComponent(g);
+        doDrawing(g);
+    }
+}

trick_sims/SIM_msd/models/graphics/Makefile

@@ -0,0 +1,36 @@
+SHELL = /bin/sh
+
+PROJECT_NAME = MsdGui
+SRC_DIR = MSD/src
+BUILD_DIR = build
+CLASSES_DIR = $(BUILD_DIR)/classes
+JAR_DIR = dist
+MAIN_CLASS = MsdGui
+
+all: jar
+
+clean:
+	rm -rf $(BUILD_DIR)
+	rm -f manifest
+
+spotless: clean
+	rm -rf dist
+
+$(CLASSES_DIR):
+	@ mkdir -p $(CLASSES_DIR)
+
+compile: | $(CLASSES_DIR)
+	javac -sourcepath $(SRC_DIR) -d $(CLASSES_DIR) $(SRC_DIR)/MsdGui.java
+
+manifest:
+	@ echo "Main-Class: $(MAIN_CLASS)" > $@
+
+$(JAR_DIR):
+	@ mkdir -p $(JAR_DIR)
+
+jar: compile manifest | $(JAR_DIR)
+	jar cvfm $(JAR_DIR)/$(PROJECT_NAME).jar manifest -C $(CLASSES_DIR) .
+	@ echo "-------------------------------------------------------------------------------"
+	@ echo "                              BUILD COMPLETE"
+	@ echo "The Java jar file (the Java Executable) is located at: $(JAR_DIR)/$(PROJECT_NAME).jar"
+	@ echo "-------------------------------------------------------------------------------"

trick_sims/SIM_msd/models/msd/include/msd.hh

@@ -0,0 +1,48 @@
+/************************TRICK HEADER*************************
+PURPOSE: Mass-Spring-Damper class header file .
+PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+
+#ifndef MSD_H
+#define MSD_H
+
+class MSD {
+public:
+
+    double a;           /* m/s2 acceleration  */
+    double v;           /* m/s velocity */
+    double x;           /* m position */
+    double m;           /* kg mass */;
+
+    double v_0;         /* *i m/s initial velocity of the mass (at t = 0) */
+    double x_0;         /* *i m initial position of the mass (at t = 0) */
+    
+    double b;           /* N.s/m damping constant */
+    double k;           /* N/m spring constant */
+    double F;           /* N force constant */
+
+
+
+    MSD(void); /* not used */
+
+    MSD(double _m, double _k, double _b, double _F,
+        double _v_0, double _x_0);
+
+     int state_deriv(void);
+     int state_integ(void);
+
+ };
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+int msd_default_data(MSD &);
+int msd_init(MSD &);
+int msd_shutdown(const MSD &);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MSD_H */

trick_sims/SIM_msd/models/msd/include/msd_numeric.hh

@@ -0,0 +1,17 @@
+/************************TRICK HEADER*************************
+PURPOSE: Msd Numeric model
+PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+#ifndef MSD_NUMERIC_H
+#define MSD_NUMERIC_H
+
+#include "msd.hh"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+#ifdef __cplusplus
+}
+#endif
+#endif

trick_sims/SIM_msd/models/msd/src/msd.cpp

@@ -0,0 +1,19 @@
+/************************TRICK HEADER*************************
+PURPOSE: MSD is a mass-spring-damper class for a trick sim.
+PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+#include <math.h>
+#include "../include/msd_numeric.hh"
+#include <float.h>
+
+MSD::MSD(double _m, double _k, double _b, double _F, double _v_0, double _x_0) {
+    m = _m;
+    k = _k;
+    b = _b;
+    F = _F;
+    v_0 = _v_0;
+    x_0 = _x_0;
+}
+
+MSD::MSD(void) {/* not used */}

trick_sims/SIM_msd/models/msd/src/msd_deriv.cpp

@@ -0,0 +1,15 @@
+/************************TRICK HEADER*************************
+  PURPOSE: ( Trick integration )
+PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+#include "../include/msd_numeric.hh"
+#include "../include/msd.hh"
+#include <math.h>
+
+int MSD::state_deriv(void) {
+    /* system equation for second derivitive */
+    a = (F - b*v - k*x)/m;
+    
+    return(0);
+}

trick_sims/SIM_msd/models/msd/src/msd_init.cpp

@@ -0,0 +1,28 @@
+/************************TRICK HEADER*************************
+PURPOSE: Set the initial data values of the MSD
+PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+
+/* Model Include files */
+#include "../include/msd.hh"
+
+/* default data job */
+int msd_default_data(MSD &M) {
+    M = MSD(
+            1.0, /* m */
+            2.0, /* k */
+            0.5, /* b */
+            5.0, /* F */
+            0.0, /* v_0 */
+            5.0  /* x_0 */
+
+    );
+
+    return 0;
+}
+
+/* initialization job */
+int msd_init(MSD &M) {
+    return 0;
+}

trick_sims/SIM_msd/models/msd/src/msd_integ.cpp

@@ -0,0 +1,31 @@
+/************************TRICK HEADER*************************
+  PURPOSE: ( Trick integration )
+  PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+#include "../include/msd_numeric.hh"
+#include "msd.hh"
+#include "trick/Integrator.hh"
+#include "trick/integrator_c_intf.h"
+#include <math.h>
+
+int MSD::state_integ(void) {
+    int ipass;
+	    load_state(
+	    	&x,
+	    	&v,
+	    	NULL);
+
+	    load_deriv(
+	    	&v,
+	    	&a,
+	    	NULL);
+	    
+	    ipass = integrate();
+
+	    unload_state(
+	    &x,
+	    &v,	
+		NULL);
+    return(ipass);
+}

trick_sims/SIM_msd/models/msd/src/msd_shutdown.cpp

@@ -0,0 +1,17 @@
+/************************TRICK HEADER*************************
+PURPOSE: (Print the final msd state.)
+PROGRAMMERS:
+    (((Scott P. Fennell) (CACI International Inc.) (January 2018) (Trick Learning Project)))
+*************************************************************/
+#include "../include/msd.hh"
+#include "trick/exec_proto.h"
+#include <stdio.h>
+
+int msd_shutdown(const MSD &M) {
+    printf("========================================\n");
+    printf("         MSD State at Shutdown     \n");
+    printf("pos = [%g], vel = [%g], acc = [%g]\n",
+             M.x, M.v, M.a);
+    printf("========================================\n");
+    return 0;
+}