10.3. Real-time control with the Simulink block

When a user generates a new solver from either the graphical Simulink interface, or the textual MATLAB or Python interfaces, several Simulink blocks are automatically created in the ‘interfaces’ folder. These blocks are useful to interface the solver with other Simulink models for simulation, or for deployment in embedded prototyping hardware using tools such as dSpace MicroAutobox or Simulink Coder.

In the following we describe the difference between the different available Simulink interfaces.

10.3.1. Input and Output Ports in the Compact Interface

For every solver, there are two Simulink interfaces generated: a standard interface; and a compact interface, which groups parameters and outputs. For problems with many parameters and outputs, the compact interface is more suitable because it reduces the number of ports and connections that need to be wired up to the rest of the Simulink model.

The criteria for grouping parameters is the following: parameters of the same type that have the same number of rows are grouped together into a single stacked parameter. These parameters are stacked horizontally, e.g. if there are two parameters mapping to eq.c, both of size 3x1, they will be grouped into a new parameter of size 3x2. The new parameter will get the name c.

To illustrate the conversion consider a problem with the following parameters and with the corresponding standard (non-compact) Simulink block:

Name	maps2data	Dimensions
Amat1	eq.D	2x4
Amat2	eq.D	3x4
Amat3	eq.D	3x4
Amat4	eq.D	3x4
linterm1	cost.f	4x1
linterm2	cost.f	4x1
linterm3	cost.f	4x1
linterm4	cost.f	4x1

For the compact Simulink block, parameters linterm1, linterm2, linterm3 and linterm4 are stacked together into a new parameter f (because the problem data they map to is cost.f). For the parameters mapping to eq.D, Amat2, Amat3 and Amat4 can be stacked into the new parameter D. Amat1 is not included into the new parameter because it has two rows and the concatenation is not possible with the other parameters, which all have three rows. Parameters are always stacked horizontally according to the stage number they map to.

Name	maps2data	Dimensions
D	eq.D	3x12
f	cost.f	4x4
Amat1	eq.D	2x4

The port dimensions of any FORCESPRO Simulink block can be checked by double-clicking the block and clicking the ‘Help’ button.