Send Double-Lane Change Scene Data

This example shows you how to use the Simulation 3D Message Set block to communicate with the 3D visualization environment when you run the double-lane change maneuver. Specifically, you use the Simulation 3D Message Set block to control the traffic signal light. For the minimum hardware required to run the example, see the Unreal Engine Simulation Environment Requirements and Limitations.

Run a Double-Lane Change Maneuver

With the 3D visualization environment enabled, run a double-lane change maneuver.

1. Create and open a working copy of the double-lane change reference application project.

   vdynblksDblLaneChangeStart

2. Enable the 3D visualization environment. In the Visualization subsystem, open the 3D Engine block mask and select Enabled. Apply the changes and save the model.

   Alternatively, at the MATLAB^® command prompt, enter this code.

    See Code That Enables 3D Environment

   % Enable the 3D visualization environment
   mdl = 'DLCReferenceApplication';
   set_param([mdl '/Visualization/3D Engine'],'engine3D','Enabled');
   save_system(mdl)

3. Run the maneuver for 30 seconds. View the simulation in the AutoVrtlEnv window.

   

    See Code That Runs Simulation

   % Run simulation for 30s.
   mdl = 'DLCReferenceApplication';
   set_param(mdl,'StopTime','30');
   save(mdl);
   sim(mdl);

Use Simulation 3D Message Set Block to Control Traffic Signal Light

1. Start the maneuver at 5 seconds. In the Lane Change Reference Generator block, set Maneuver start time to 5.

    See Code That Sets Parameters

   % Start simulation at 5s.
   mdl = 'DLCReferenceApplication';
   set_param([mdl '/Lane Change Reference Generator'],'t_start','5');
   save(mdl);

2. Navigate to the Visualization > 3D Engine subsystem. Right-click the 3D Engine block and select Mask > Look Under Mask. In the Visualization > 3D Engine > 3D Engine subsystem, insert these blocks:

   • Simulation 3D Message Set

   • Repeating Sequence Stair

3. Set the Simulation 3D Message Set block parameters so that the block sends traffic signal data to the double-lane change scene. Set these block parameters, apply the changes, and save the model.

   • Signal name, SigName to TrafficLight1

   • Sample time to -1

   

   This table provides the scene traffic signal light color that corresponds to the WriteMsg value in the Double Lane Change scene.

   Simulation 3D Message Set Block WriteMsg Value	TrafficLight1 Color
   0	Red
   1	Yellow
   2	Green

   Alternatively, at the MATLAB command prompt, enter this code.

    See Code That Sets Parameters

   % Set Simulation 3D Message Set block parameters
   visualss='DLCReferenceApplication/Visualization/3D Engine/3D Engine';
   set_param([visualss  '/Simulation 3D Message Set'],'SigName','TrafficLight1');
   set_param([visualss  '/Simulation 3D Message Set'],'Ts','-1');
   save_system(mdl)

4. Set the Repeating Sequence Stair block parameters to send a command that corresponds to red, yellow, and green traffic light signals. Set these block parameters, apply the changes, and save the model.

   • Vector of output values: to [0 0 0 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2].'

   • Sample time to 1

     

   • Output data type to int32

     

   Alternatively, at the MATLAB command prompt, enter this code. Apply the block changes and save the model.

    See Code That Sets Parameters

   % Set Repeating Sequence Stair block parameters
   visualss='DLCReferenceApplication/Visualization/3D Engine/3D Engine';
   open_system([visualss  '/Repeating Sequence Stair']);
   set_param([visualss  '/Repeating Sequence Stair'],'OutValues',"[0 0 0 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2].'");
   set_param([visualss  '/Repeating Sequence Stair'],'tsamp','1');
   set_param([visualss  '/Repeating Sequence Stair'],'OutDataTypeStr','int32');

5. Connect the blocks as shown. Confirm the block parameters and signal connections. Save the model.

   

6. Verify that the Simulation 3D Message Set block executes before the Simulation 3D Scene Configuration block. That way, Simulation 3D Message Set prepares the signal data before the Unreal Engine^® 3D visualization environment receives it. To check the block execution order, right-click the blocks and select Properties. On the General tab, confirm these Priority settings:

   • Simulation 3D Scene Configuration — 0

   • Simulation 3D Message Set — -1

   For more information about execution order, see Control and Display Execution Order.

7. Run the maneuver. As the simulation runs, in the AutoVrtlEnv window, you can see the TrafficLight1 light change from red to yellow to green.

   

   Time Range (s)	WriteMsg Value	TrafficLight1 Color
   0–3	0	Red
   3–5	1	Yellow
   5–30	2	Green