Urdf importer,i get a very big usd file,

I use the urdf importer to import a car,the mesh file is about 90Mb,and i use the mesh merge tool in isaac sim.finally i got a file about 200Mb.When i try to remove the car prim to a different place,the whole system crash,not only the isaac sim,but also the ubuntu 18.04.How can i solve this problem?


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