CAGE User's Guide

Setting Up Calibrations

Start CAGE by typing

• cage
  

at the MATLAB prompt.

Note    If you have a CAGE session open, select File -> New -> Project.

Before you can perform a calibration, you must set up the variable dictionary and models that you want to use.

Setting Up Variables

To set up the variables and constants that you want to use in your calibration:

1. Click Variable Dictionary in the Data Objects pane of CAGE

   

The Variable Dictionary displays all the variables, constants, and formulas in a session.

There are two ways in which you can set up variables:

• Import a variable dictionary
• Add variables and constants to your session

After setting up your variables and constants, you can export the variable dictionary to use in other calibrations.

Importing a Variable Dictionary

To import a variable dictionary:

1. Select File -> Import -> Variable Dictionary.
2. Select the tutorial.xml file found in matlab\toolbox\mbc\mbctraining and click Open.

This imports a set of variables and a constant. In our example, the variable dictionary contains

• N, engine speed
• L, load
• A, AFR
• The stoichiometric constant, stoich

Your display should resemble the following.

Adding and Editing Variables and Constants

To add a variable for the spark angle:

1. Click  in the toolbar. This adds a new variable to your dictionary.
2. Select Edit -> Rename to rename the variable.
3. Enter SPK as the name.
4. Set the range of the variable by entering -5 as the Minimum and 50 as the Maximum.

The variable dictionary enables you to specify different names for the same variable, and also give descriptions of variables. For example, the variable spk might be referred to as S or spark in other models.

To ensure that CAGE recognizes an instance of S or spark as the same as spk, specify the aliases of SPK:

5. Enter S, spark in the Alias edit box.
6. Enter Spark advance (deg) in the Description edit box.

Note    The Variable Dictionary is case sensitive: s and S are different.

The variable dictionary enables you to specify a preferred value for a variable. For example, in the preferred value of the variable, AFR is set as the stoichiometric constant 14.35.

7. Enter 25 in the Set Point edit box to specify the preferred value for spk.

For more information about the variables, see Setting Up Your Variable Items.

What Are Feature Calibrations?

Setting Up Models