Assertion failed: VehMesh != nullptr UE-AutoVrtlEnv

I was trying to simulate theVTOLTiltrotor in Unreal Engine. Whenever I tried to run the simualtion using Default Scenes in Simulation 3D Engine block I am facing this error

Assertion failed: VehMesh != nullptr

[File:C:\TEMP\Bsim3d_2535942_3008\AutoVrtlEnv\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dVeh.cpp] [Line:

254]

Failed to load

SkeletalMesh'/Game/Maps/VTOLDEMO/VTOLAsset.VTOLAsset'. Please

specify a valid mesh path.

I tried everything, I followed all the steps made sure the verison of Matlab and Unreal Engine are compatible with each other. I am just trying to use the default packages without any modifications to the code.

I tried uninstalling and installing both matlab and unreal engine also tried in another system with fresh installation, even tried running both Matlab and Unreal Engine with admin privileges.

Answer 1

[Nishan Nekoo]

Hi @Chaithanya Chowdhary, what version of MATLAB are you using?

If its R2024b, did you follow all the instructions on this page? https://www.mathworks.com/help/uav/ug/visualize-vtol-flight-mission-over-urban-environment.html

You will need to manually import the VTOL Vehicle into Unreal Engine to use it in Unreal Engine Scenes. In particular, this instruction on modifying the path in the VTOL block is important:

To copy the reference path to this asset, right-click the VTOLAsset skeletal mesh object in Content Browser pane and click Copy Reference.

In the Simulation 3D UAV Vehicle block of the Photorealistic subsystem, set the Type parameter to Custom and then set the Path to custom mesh parameter to the reference path.

Hope that helps,

Nishan

[Chaithanya Chowdhary]

Hey @Nishan Nekoo Thanks for responding.

I am using Matlab R2024a and Unreal Engine 5.1. I followed each and every step carefully as mentioned in the visualize-vtol-flight-mission-over-urban-environment. Still I am facing errors.

Please refer below screenshot. When I disabled the plugin MathWorkSimulation the project didn't crashed. Seems like the plugin MathWorkSimulation is causing the issue.

[Nishan Nekoo]

Hey @Chaithanya Chowdhary sorry to hear that you are running into this crash. Just to verify, I tried replicating the instructions from that link on my end and was able to simulate without any errors. There might be an issue with your environment setup.

To understand where the issue lies, can you copy a new project using this function:

sim3d.utils.copyExampleSim3dProject("C:/project")

You might need to first delete the folder "MathWorks" at C:\Program Files\Epic Games\UE_5.1\Engine\Plugins\Marketplace

Then try running a co-simulation with a new Simulink model with only the Simulation 3D Scene Configuration block - with the Scene Source set to Unreal Editor and the path specified to the project you just created.

Nishan

[Chaithanya Chowdhary]

Hey @Nishan Nekoo

I tried everything.

Deleted the Folder Mathworks in C:\Program Files\Epic Games\UE_5.1\Engine\Plugins\Marketplace and copied the new project again and tried running the simulation.

Unreal Editor freezed and then crashed with the same message.

[Chaithanya Chowdhary]

@Nishan Nekoo Please review the below log from unreal engine

LoginId:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

EpicAccountId:xxxxxxxxxxxxxxxxxxxxxxxxxxxx

Assertion failed: VehMesh != nullptr [File:C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dVeh.cpp] [Line: 254] Failed to load SkeletalMesh'/Game/Maps/VTOLDEMO/VTOLAsset.VTOLAsset'. Please specify a valid mesh path.

UnrealEditor_MathWorksSimulation!ASim3dVeh::ConfigureDefaultMesh() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dVeh.cpp:254]

UnrealEditor_MathWorksUAV!ASim3dQuadRotor::Sim3dSetup() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksUAV\Private\Sim3dQuadRotor.cpp:29]

UnrealEditor_MathWorksSimulation!ASim3dActor::BeginPlay() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dActor.cpp:156]

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_MathWorksSimulation!ASim3dActor::CreateInstance() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dActor.cpp:90]

UnrealEditor_MathWorksSimulation!ASim3dVeh::CreateInstance() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dVeh.cpp:52]

UnrealEditor_MathWorksSimulation!ASim3dActor::Create() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dActor.cpp:36]

UnrealEditor_MathWorksSimulation!ASim3dLevelScriptActor::CreateActorInScene() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dLevelScriptActor.cpp:673]

UnrealEditor_MathWorksSimulation!ASim3dLevelScriptActor::CreateActorsInScene() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dLevelScriptActor.cpp:501]

UnrealEditor_MathWorksSimulation!ASim3dLevelScriptActor::Tick() [C:\TEMP\Bsim3d_2703290_6860\home\Desktop\SP\plg\MathWorksSimulation\HostProject\Plugins\MathWorksSimulation\Source\MathWorksSimulation\Private\Sim3dLevelScriptActor.cpp:135]

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_Engine

UnrealEditor_UnrealEd

UnrealEditor_UnrealEd

UnrealEditor

UnrealEditor

UnrealEditor

UnrealEditor

UnrealEditor

UnrealEditor

kernel32

ntdll

[Nishan Nekoo]

Hi @Chaithanya Chowdhary, it looks like this error stack included some vehicles in the simulation.

Is this the same error when there is only one block in the model - the Simulation 3D Scene Configuration block? Can you send me a screenshot of the model with Unreal Editor side by side with the error/crash.

Can you provide a screenshot of the MathWorks folder? I'd like to see what plugins you have downloaded.

Nishan

[Chaithanya Chowdhary]

Yeah this is the same error I am facing. I'll attach all the screenshots following all the steps and also the crash logs from Unreal Engine.

[Nishan Nekoo]

Hi @Chaithanya Chowdhary, can you show me where the VTOLAsset is in your Content Browser? For example, mine is located here:

The instructions in the documentation ask to create an EVTOL folder, and add the asset there. Then right click on the asset and use the reference path in the Simulink block. It appears to me that your reference path 'SkeletalMesh'/Game/Maps/VTOLDEMO/VTOLAsset.VTOLAsset' is the default reference path and does not point to the EVTOL mesh that you imported yourself.

Unfortunately, if you are still running into issues after fixing the above, please reach out to [e-mail] for further assistance.

[Chaithanya Chowdhary]

Hey @Nishan Nekoo I copied the reference of VTOL and used the reference path in the Simulation 3D UAV Vehicle block. But still the error is same. If the disable the MathworkInterface plugin in the project, atleast I was able to run the level in the Unreal Editor. But the simulation is not working.

Thanks for your support and appreciate your effort in helping me in resolving the issue.

I will email support team detailing the issue.

[Chaithanya Chowdhary]