MATLAB: How to offset the start of the Function Call Generator block so that it first triggers its subsystem at something other than time instant ‘0’ in Simulink 7.9 (R2012a)

delayphasesimulink

I would like to start the Function-Call Subsystem at something other than 0. i.e.the subsytem should execute via a function call generator at

t = [1, 2, 3, 4, ...]

Instead of

t = [0, 1, 2, 3, ...]

Best Answer

The ability to set an arbitrary initial offset for the Function-Call Generator Block is not available in Simulink.

As a workaround you can use an 'If Action Subsystem' block in the model (see custTest.mdl attached). The model can work as explained below:

1. The 'If Action Subsystem' block is triggered by an 'If' block which has a Pulse Generator as the input.

2. The pulse generator can be set to have whatever phase delay and period you would like.

3. In the 'If Action Subsystem' block, you can use a clock block as an input to any function block you would like to use.

Related Solutions

MATLAB: How to delay a Function-Call signal in Simulink 7.0 (R2007b)

The unit delay block does not support-function call signals in Simulink 7.6 (R2010b). There are several possible workarounds, including using Stateflow charts and/or triggered subsystems. The attached model is one example.

The Function-Call Delay block, within the example model, is itself a Function-Call subsystem that uses its function trigger to activate an Enabled subsystem. The internal function trigger signal is a numerical signal rather than a function-call and therefore can be delayed. Additionally, the Enabled subsystem contains a Function-Call generator block to propagate your original function call at a later time.

The original function call is triggered at 4 seconds, but the unit delay block causes the Delayed Subsystem block to be called at 4.01 seconds.

MATLAB: How is the FIND_SYSTEM used to find “IF Action Subsystem” in Simulink 8.2 (R2013b)

The ability to query a subsystem directly to see if it is an If-Action-, Triggered-, Enabled-, or Function-call subsystem is not available in Simulink.

As a workaround query the subsystem to see if it contains an action port with the following commands:

 ports = get_param(subsystem,'PortHandles');
 conditional = ~isempty(ports.Enable) || ~isempty(ports.Trigger) || ~isempty(ports.Ifaction);

For instance, you can find and assign values to If-Action subsystem with the following commands:

 b=find_system(gcs,'LookUnderMasks','all','BlockType','SubSystem'); 
 for j=1:numel(b) 
     ports = get_param(b{j},'PortHandles'); 
     if (~isempty(ports.Ifaction))
        ...
     end
 end

Best Answer

Related Solutions

MATLAB: How to delay a Function-Call signal in Simulink 7.0 (R2007b)

MATLAB: How is the FIND_SYSTEM used to find “IF Action Subsystem” in Simulink 8.2 (R2013b)

Related Question