Setting Up a Tradeoff Calibration

On this page…
Creating a Tradeoff Adding Tables to a Tradeoff Calibration Displaying the Models

Creating a Tradeoff

Start CAGE by typing

cage

at the MATLAB prompt.

Before you can calibrate the lookup tables, you must set up the calibration.

1. Select File > Open Project (or the toolbar button) to choose the tradeoffInit.cag file, found in the matlab\toolbox\mbc\mbctraining directory, then click OK.

   The tradeoffInit.cag project contains two models and all the variables necessary for this tutorial. For information about how to set up models and variables, see Variables and Models in the CAGE documentation.

2. To create a tradeoff calibration, select File > New > Tradeoff.

   This takes you to the Tradeoff view. You need to add tables and display models to the tradeoff, which are described step by step in the following sections:

   • Adding Tables to a Tradeoff Calibration.

   • Displaying the Models describes how you display the models of torque and NOX emissions.

Back to Top

Adding Tables to a Tradeoff Calibration

The models of torque and NOX are in the current session. You must add the lookup table to calibrate.

Both models have five inputs. The inputs for the torque and NOX models are

• Exhaust gas recycling (EGR)

• Air/fuel ratio (AFR)

• Spark angle

• Speed

• Load

For this tutorial, you are interested in the spark angle over the range of speed and load.

To generate a lookup table for the spark angle,

1. Click   (Add New Table) in the toolbar. This opens the Table Setup dialog.

   

2. Enter Spark as the table Name.

3. Check that N is the X input and L is the Y input (these are selected automatically as the first two variables in the current Variable Dictionary).

4. Enter 10 as the size of the load axis (Rows).

5. Enter 13 as the size of the speed axis (Columns).

6. Click Select to open the dialog Select Filling Item.

   

   Select the radio button Display variables, then select SPK to fill the table and click OK.

7. Click OK to close the Table Setup dialog.

Before you can perform the calibration, you must display the models.

Back to Top

Displaying the Models

For this tutorial, you are comparing values of the torque and NOX models. Thus, you need to display these models.

To display both models,

• Click    Add Model to Display List in the toolbar twice. This will move both available models into the Display list.

• Alternatively, Shift-click to select both models in the Available Models list and click  to include both models in the current display. In this case you want to include all available models. You can click to select particular models in the list to display.

The Display Models pane following shows both models selected for display.

You can now calibrate the tradeoff.

Back to Top

What Is a Tradeoff Calibration?

Performing the Tradeoff Calibration

© 1984-2012- The MathWorks, Inc.    -   Site Help   -   Patents   -   Trademarks   -   Privacy Policy   -   Preventing Piracy   -   RSS