CAGE User's Guide

About Normalizers

CAGE distinguishes between the normalizers and the tables that they belong to.

Using models to calibrate lookup tables enables you to perform analysis of the models to determine where to place the breakpoints in a normalizer. This is a very powerful analytical process.

It is important to stress that in CAGE a lookup table can either be one dimensional or two dimensional. One-dimensional tables are sometimes known as characteristic lines or functions. Two-dimensional tables are also known as characteristic maps or tables. This is important to stress, as normalizers are very similar to characteristic lines.

For example, a simple strategy to calibrate the behavior of torque in an engine might have a two-dimensional table in speed and relative air-charge (a measure of the load). Additionally, this strategy might take into account the factors of air-fuel ratio (AFR) and spark angle. Each of these compensating factors is accounted for by the use of a simple characteristic line. In CAGE, these characteristic lines are one-dimensional tables. In the example strategy, there are the following tables and normalizers:

• One characteristic map: the torque table
• Six characteristic lines:
• Two tables: one for AFR and one for spark angle
• Four normalizer functions: speed, load, AFR, and spark angle

Notice also that a breakpoint is a point on the normalizer where you set values for the lookup table.

Thus, when you calibrate a normalizer you place the individual breakpoints over the range of the table's axis.

Normalizers

Calibrating the Normalizers