Sample time mismatch between IF block and Action Port in Action Subsystem.

Question

Dhrupad 2024-9-23

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2154760-sample-time-mismatch-between-if-block-and-action-port-in-action-subsystem

回答： Jaimin 2024-12-24，5:08

Hello everyone,

I wanted to encrypt the subsystems of a model, to do that I added the unit delay(to break algebric loop) and tried to convert to model reference. But am receiving this error - 'Sample time [0, 1] of '.../If Action Subsystem/Action Port' does not match the discrete sample time of the If block '.../If' controlling its execution.' I am getting this error after adding the unit delay block, the IF block is present in one of the subsystems. Is there any other way to encrypt or is there any way I can solve this sample time issue.

Please explain in simple terms as I am relatively new to simulink.

Thanks in advance,

DV

4 个评论
显示 2更早的评论隐藏 2更早的评论

Malay Agarwal 2024-9-25

编辑：Malay Agarwal 2024-9-25

The model seems to be missing some files and variables requires to run it. Could you add those files, variables?

Francisco J. Triveno Vargas 2024-10-9

HI,

Initially, try to change to fixed step and select one Sample Time.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Jaimin 2024-12-24，5:08

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2154760-sample-time-mismatch-between-if-block-and-action-port-in-action-subsystem#answer_1556340

Hi @Dhrupad

The error you are experiencing is due to a discrepancy in sample times between the “If” block and the “Action Port” within the “If Action” Subsystem. This usually occurs when the “If” block has a discrete sample time, but the Action Subsystem anticipates a different sample time.

Steps to Resolve the Sample Time Issue

Check Sample Times:

Open the “If” block and check its sample time settings.
Ensure that the sample time of the If block matches the sample time of the Action Subsystem.

Adjust Sample Times:

Set the sample time of the “Action” Subsystem to match the “If” block's sample time.
Alternatively, you can set both to inherit the sample time by using “-1” (which means they will inherit the sample time from the parent system).

Use Rate Transition Blocks:

If you need to manage different sample times, consider using a Rate Transition block to handle the transition between different sample rates.

Model Reference Conversion:

When converting to a model reference, ensure that all blocks within the subsystem have compatible sample times and that any algebraic loops are properly broken.

For more information kindly refer following MathWorks documentation.

if block: https://www.mathworks.com/help/simulink/slref/if-then-else-blocks.html

Rate Transition Block: https://www.mathworks.com/help/simulink/slref/ratetransition.html

I hope this will be helpful.