Hi, thank you for your response! First of all, I may have to apologise for my language skills and I really appreciate that you are willing to listen to my ideas. I'd like to describe my question again. I have finished a complete complex experiment, including around 10k granular objects, two objs of my own, one container by using *utils::AddBoxGeometry* and several links and motors, such as *ChLinkMotorRotationSpeed*、*ChLinkMotorLinearSpeed*、*ChLinkMateFix*. I achieved it by using *the MCORE module*, although it can speed up the program by using multiple threads, it still took 2 hours four one time simulation.
Now I am considering using the reinforcement learning afterwards, so it is important to improve the simulation speed. I am wondering if I can use *Chrono::GPU* only for my granular objects, and all other content remains the same by using *the MCORE module.* More specifically, I plan to use both *ChSystemMulticoreSMC* and *ChSystemGpuMesh* in one cpp. The reason I want to do this is because *Chrono::GPU* is more like a separate module, some of the functions I need for simulation can't be found in *Chrono::GPU*, but can be found in *the MCORE module* and are already realized through my previous efforts. I also note that *Chrono::GPU *quote ChronoEngine_GPU、ChronoEngine_irrlicht、ChronoEngine_multicore、ChronoEngine_opengl、ChronoEngine_postprocess、ChronoEngine_robot and *ChronoEngine_multicore(* *the MCORE module* *) *is the one which I used now. So I can use MCORE-functions in cpps in *Chrono::GPU*，by including the .h insteading of modify the CMakeLists.txt. I tried and felt if this idea was unattainable. Because I need to create two systems in one cpp. Meanwhile, for visualization, *opengl::ChVisualSystemOpenGL* is used in *the* *MCORE module *and *ChGpuVisualization* is used in *the **Chrono::GPU *and I can't find an interface between the two which means they can't be showed in one window. I don't know how to solve this problem anymore and I wonder if you have any suggestions. I really appreciate your help! 在2022年11月10日星期四 UTC+8 13:29:20<Ruochun Zhang> 写道： > Hi, > > I hope someone can provide better help on the linkage issue. What I can > say is that you can try building it with cuda11.6 and the newest gcc. If > you are using cuda11.8, or an ancient version of cuda or gcc, I cannot be > sure. I've been building it with the said configuration with no problem, on > Linux or Windows. > > About Chrono::GPU's usage, yes it supports obj meshes. I am not sure about > what you meant by multi-core acceleration. I might, if you elaborate a bit. > And Chrono::GPU should interact with Chrono just fine, for that maybe you > can have a look at the *ballcosim *demo. > > If you care about polydisperse spherical particles or complex shaped > particles, then DEM-Engine is the way to go. You can start using it now. > Indeed, documentations are being added. I can drop you a message when it > becomes more accessible. Right now, I attached a snippet from one of my > previous emails, to help you understand how to build this tool on Linux. In > terms of using it, I'd start with checking out and running its demos. And > then, the methods in *API.h* are mostly commented, which for now, may > serve as an ad-hoc documentation for you to understand what some of its > basic usages are. > > Thank you, > Ruochun > On Wednesday, November 9, 2022 at 2:19:40 AM UTC-6 [email protected] wrote: > >> Hi, thank you very much for your help! >> After last mail, I choosed to use the multicore, the simulation took 2 >> hours every time now, because I was constantly adding requests and >> features and the number of bodies comes to 10k. Meanwhile, I bought a 3080 >> and a new computer. I am considering using the reinforcement learning >> afterwards, so it is important to improve the simulation speed. >> I have studied your response several times，I am wondering if I can only >> use Chrono::GPU for my particle-related content, and all other content >> remains the same, such as multi-core acceleration, loading my own obj. More >> specifically, I plan to use both ChSystemMulticoreSMC and ChSystemGpuMesh. >> When compile the project, there are errors "LNK2019：Unresolvable external >> symbols" in every functions defined in GPU and used in the Muticore and I >> feel this is a deeper issue involving linkers. So I would like to ask for >> guidance or is there another way to use the Chrono::GPU as a DEMsolver only >> for the particles. >> And I learned something about projectchrono >> <https://github.com/projectchrono>/DEM-Engine >> <https://github.com/projectchrono/DEM-Engine>, but I found how to >> Install DEM-Engine and the DEM-Engine usage are still waiting to be >> added, I would love to try it if I could. >> Thank you again! >> >> 在2022年9月24日星期六 UTC+8 14:45:22<Ruochun Zhang> 写道： >> >>> Hi, >>> >>> The GPU module does benefit a lot from more recent hardware. If your >>> test case does not feature a huge number of bodies, say some 10k, then >>> multicore can be a good choice. It probably requires less learning from you >>> too. >>> >>> It should be noted that Chrono::GPU is not "Chrono on GPU". Most Chrono >>> core classes and methods cannot be used in Chrono::GPU. For all >>> purposes, Chrono::GPU can be seen as a standalone DEM solver for >>> monodisperse spherical particles, implemented on GPU. It should be used to >>> simulate granular materials, and it can interact with Chrono (core) so that >>> it becomes possible to bring a small number of more complex objects (such >>> as your spoon) into the simulation as well. So if you would like to use >>> Chrono::GPU, you have to start from its demos, to learn how to use its own >>> methods to instantiate and manage granular particles. Chrono::GPU's main >>> advantage is being fast. If your simulation has to involve millions of >>> granular particles, then multicore will not do and GPU is the choice. >>> >>> More specifically, *CreateCylindricalContainerFromBoxes* is not a >>> Chrono::GPU thing at all. *cohesion_ratio* is about the cohesion >>> between Chrono::GPU particles, and it has nothing to do with gravity, which >>> is set by *SetGravitationalAcceleration* in Chrono::GPU. >>> >>> On a different note, Chrono's DEM/granular support on GPU is moving >>> towards a new direction. The support for complex granular particle shapes >>> will be added and it will become a duo-GPU solver. It will be based on >>> SBEL's >>> new DEM Engine <https://github.com/uwsbel/DEM-Engine>. Apart from being >>> more general and having higher efficiency, the usage of it is similar to >>> Chrono::GPU, as a standalone helper to Chrono core which manages the >>> granular part of the simulation, or work on its own as a dedicated DEM >>> solver. If from the previous conversation you believe Chrono::GPU is for >>> you, then likely this package will be of interest. More documentations and >>> user guides are being added to it. But again, it does benefit from recent >>> GPUs though. >>> >>> Thank you, >>> Ruochun >>> >>> On Sunday, September 18, 2022 at 2:13:24 AM UTC-5 [email protected] wrote: >>> >>>> hello there, >>>> I am tring to perform a simulation which I want to put an object like a >>>> spoon and scoop the sand(granular objects) to see the force in the process. >>>> I find that demo_GPU_mixer.cpp demo can be referenced, but I am not >>>> sure whether I need to add a container holding those sand and give the >>>> granular objects gravity. If this is so, should I use >>>> *CreateCylindricalContainerFromBoxes* to add container and use >>>> *cohesion_ratio* in the .json to add the gravity? Also, I am sad that >>>> I have a poor GPU so that it really take a long long time to run the gpu >>>> module. >>>> Then I find that there are also some granular objects demos in the >>>> multicore module, I find some demos about a container with granular >>>> material. And I can run those demos faster. >>>> Now I am confused about what thing to do next is much better. >>>> >>>> Any help will be appreciated, thank you so much in advance. >>>> >>> -- You received this message because you are subscribed to the Google Groups "ProjectChrono" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/projectchrono/2ae78d08-7402-4212-90f9-a95e0f56e713n%40googlegroups.com.
