Output Error of ultrasonic​DetectionG​enerator in Simulink

The measurement error that occurred previously is no longer happening.

If no input is provided to the Scenario Reader, no errors occur.

However, when I start providing values through parkEgo in the Scenario, the ultrasonicDetectionGenerator fails to produce any output and continuously encounters errors.

The simulation does not terminate due to the error, but it remains stuck without producing any output, and when I press ctrl+c in the Matlab command window, it always shows an error in the Implement of ultrasonicDetectionGenerator.

https://kr.mathworks.com/matlabcentral/answers/2137952-measurement-error-of-ultrasonic-sensor-in-driving-scenario-designer/?s_tid=ans_lp_feed_leaf

Due to the above issue, I am currently using the prerelease version 2024b.

시뮬레이션 중에 오류가 발생하여 시뮬레이션이 종료되었습니다

원인:

• 'ultrasonicDetectionGenerator'의 'stepImpl' 메서드를 호출할 때 MATLAB System 블록 'AIV_robot/Environment/Simulation/Ultrasonic Sensor Processing/Ultrasonic5'에서 오류가 발생했습니다.
• 프로그램 중단(Ctrl+C)이 감지되었습니다.

An error occurred during the simulation, causing it to terminate.

Cause:

• An error occurred in the MATLAB System block 'AIV_robot/Environment/Simulation/Ultrasonic Sensor Processing/Ultrasonic5' while calling the 'stepImpl' method of 'ultrasonicDetectionGenerator'.
• Program interruption (Ctrl+C) was detected.

[Angelo Yeo]

Can you share your model to reproduce the issue?

Also, let us know the exact steps to reproduce it.

[정호 윤]

@Angelo Yeo

How can I share the file with you?

If you need the file, I can send it to you via email.

Here's how to create it:

1. Simply export an actor equipped with Ultrasonic sensors from the driving scenario designer to Simulink, and you will see the blocks created.
2. Then, click on the scenario Reader block to add the input, and when you run it, you will notice that it keeps showing errors.

[Angelo Yeo]

Please use a paperclip icon. If you can't proceed further, let me know. I can contact you via email.

[정호 윤]

@Angelo Yeo

When creating an agent through rlEnv.m and running Simulink(AIV_robot), no error messages appear, but it remains still.

In this situation, pressing Ctrl+C on the MATLAB command line always shows it stopping at Ultrasonic.

Thank you very much for your help.

[Angelo Yeo]

I found some issues in your Simulink model and fixed it. It runs okay in R2024b Prerelease. Can I contact you via email?

[정호 윤]

@Angelo Yeo

Thank you very much for your assistance!

My email address is ...

(Edited by Angelo and removed the email address for privacy purpose)

Answer 1

[Angelo Yeo]

First, please check if the path to scenario file for Scenario Reader is correct. The reason you ran into an error from "Ultrasonic Detector" block is that the block cannot receive proper scenarios and cannot generate bus variables out of them. Hence, you should check availability of the scenario file.

Second, the action value output from the Robot Controller is directly connected to the Environment, which creates an algebraic loop. To prevent this, please try adding a unit delay block to your current model.

If you take the above steps, you will see that the reinforcement learning agent gets trained without any problems.

You can find the fixed model in the attachment. Feel free to post further comments or questions if you have.