Using Simulink Block

For synchronous simulation of control design tool and CoLink, following five steps are required as shown in Figure 2.

Figure 1  Five-step process

Step I

1.  Build or Open the CoLink model

•     Any CoLink Model can be used in this interface.

2.  Make sure the CoLink model is correct

•     The CoLink model must be free of simulation errors. The modeling errors must be fixed in this step. If not, it is very difficult to modify the model in co-simulation.

Step II

1.  Identify inputs and outputs

•     Drag and Drop Simulink block in modeling window.

•     Define the number of inputs and outputs of block.

•     Connect input ports and output ports to other blocks with lines.

2.  Enter the name of M-file to create RecurDyn plant block and click Export

•     M-file name and sampling period. M-file sends necessary data to MATLAB/SIMULINK for synchronous simulation.

Step III

Build Simulink model with RecurDyn Plant block

1.  Run the MATLAB program.

2.  Change the working directory to the directory that has the M-file and the CoLink Model.

3.  In the MATLAB command window, type M-File name.

4.  In the MATLAB command window, type makerd.

5.  A new Simulink window with RecurDyn Plant block appears.

6.  Open a new Simulink model window.

7.  Drag and drop RecurDyn Plant block on the new Simulink model window.

8.  Design the control system with the pasted plant.

9.  Terminate MATLAB program.

•     Reserved variables

•    CoLink_model: CoLink plant file name

•    CoLik_inputs: Strings of CoLink input names

•    CoLink_outputs: Strings of CoLink outputs names

•    RecurDyn_controltimestep: sampling period for co-simulation

Step IV

Set parameters for batch job of Simulink.

1.  Enter the executable file name and the installation directory of MATLAB program.

2.  Enter the name of M-File to run Simulink model to be used for the batch job of Simulink Model.

3.  Enter the name of Simulink model that is built for co-simulation with CoLink.

Step V

Co-Simulation

•     Simulate CoLink. CoLink automatically execute MATLAB program and simulate Simulink model. Then Simulink model used in co-simulation must be closed.