Total testspeed runtime for `2humanoids100.xml` reduced by 19.6% (49.5 -> 39.8s).
PiperOrigin-RevId: 910608140
Change-Id: Ided0ae5bdb8e4e8196f84e08354a9ae8cfa5b626
This change introduces MjVFS, an explicit object to mirror the C mjVFS. This is meant to replace the MjSpec.assets dict. This latter while convenient guides users towards harmful authoring patterns with respect to data duplication and spec attachment workflows. Making VFS management explicit should encourage better memory usage and allow us to make better compile time optimizations.
From this change, `spec.assets` is deprecated. However we will temporarily support backwards compatibility due to the wide spread usage. An error will be thrown if calling code tries to use a spec that uses both the assets dict and the new MjVfs.
PiperOrigin-RevId: 908772050
Change-Id: I77c6d0369307fc300c954768fed17401261e18da
When elastic2d="stretch" is set on an interpolated flexcomp, treat the bounding box boundary as membrane elements rather than volumetric cells. This computes plane-stress stiffness over the boundary faces and updates the runtime force/derivative kernels accordingly.
Interior vertex tracking (moving vertices that follow the deforming shell) is not yet implemented so all mesh vertices need to be on the bounding box surface or the background grid should have no interior nodes (i.e. cellcount should be 1 on at least one axis).
PiperOrigin-RevId: 907654080
Change-Id: I51b90e2f6a1d1b036f9604e42de20e377dc5d3f9
Total testspeed runtime for `2humanoids100.xml` reduced by 27.6% (63.4 -> 49.5s) due to early termination on small islands
PiperOrigin-RevId: 906910915
Change-Id: If55ad468c3680ef44eda7000455a77f8003b3122
Do not allow a mix of `elastic2d != none` with `dof = trilinear` since the latter assumes 3d elasticity.
Also, do not assume that `flex_interp > 0` in the engine. This will enable to use, e.g., `flex_interp = -1` to mean a linear surface finite element instead of a 3d finite element which is currently identified with `flex_interp = 1`.
PiperOrigin-RevId: 903852035
Change-Id: Ia6290b4a05e9e510ffb7f36d141cd525b40d3110
Previously specs that were attached to some parent spec would resolve its asset paths relative to the modelfiledir of the parent spec. This means path resolution would change depending on the source of the parent spec. Instead, this change makes asset file path resolution relative to the "owning spec" i.e. the spec where the asset was created.
This enables workflows such as loading a parent spec via resource provider, then loading a child spec via `from_zip` or in memory providing `spec.assets` and resolution will work as intended.
PiperOrigin-RevId: 903207910
Change-Id: Ia58020ab372a3ceadf31e804d145e2ae53d8e5f9
Each mjEQ_FLEXSTRAIN equality now represents a single cell within a flex. This allows for more efficient sparse Jacobian computation by only considering the degrees of freedom of the nodes within each specific cell. This change gives a speedup of about 10x on a 3x3x3 model.
PiperOrigin-RevId: 902164069
Change-Id: I78eedf1d5cf39b8989fe9863c22d164922fc0efb
The flex interpolation stiffness matrix within the implicit/implicitfast solvers is now built and factorized in a banded format instead of a dense one. This involves:
- Calculating the bandwidth based on the sparsity of the mass/damping matrix and the connectivity within flex cells.
- Allocating and populating a banded matrix `H`.
- Using `mju_cholFactorBand` and `mju_cholSolveBand` for factorization and solving.
This change improves performance for flexes with many DOFs but local coupling.
PiperOrigin-RevId: 901297952
Change-Id: I3efe06353d1903ea65ab30dc49685cede228bb68
This change introduces a `flex_cellcount` field to `mjModel` to specify the number of cells in each dimension for interpolated flexes. The stiffness computation, passive force calculation, and Jacobian derivatives are updated to operate on a per-cell basis, significantly improving performance by localizing computations to the nodes within each cell.
PiperOrigin-RevId: 901216393
Change-Id: Ic23132e609de11e71bb7fef8d1f139daad2ec264
This change introduces `nflexstiffness` and `flex_stiffnessadr` to allow flex stiffness matrices to have sizes other than the fixed 21 per element. Higher-order flexes can now store larger stiffness matrices based on their number of nodes. The `flex_stiffnessadr` array provides the starting index for each flex's stiffness data within the `flex_stiffness` array.
PiperOrigin-RevId: 899632263
Change-Id: Ie49182c46c3777acf0c6b492345edfcf62fb5e44
This default forces users to use the `spec.assets` dictionary or to do other filepath gymnastics when loading URDF. Instead we encourage users to just modify file paths directly if necessary.
PiperOrigin-RevId: 899009853
Change-Id: I4bb84606a95b65be79ccc77ccbe78062d6de8773
This removes the need to load these decoders via mj_loadAllPluginLibraries when using MuJoCo built with CMake. Other plugins are unchanged.
PiperOrigin-RevId: 897114719
Change-Id: Iee914cc5e05798186f384a67901f1cf86bc2f887
- Remove `lugre:viscous`, should now be added directly to actuator `damping`. Trying to do this for the user was incompatible with default inheritance (compounding instead of overriding).
- Move voltage limiting from the `saturation` to the `controller` attribute.
- Fix indexing issues in default inheritance.
PiperOrigin-RevId: 897087642
Change-Id: I5388c2633e15c7e223992e7eb5d6a28db75a6438
Previously on MSVC we used DllMain to register plugins, you cannot have multiple definitions of DllMain in a single unit so you would get errors if you tried to register two plugins. This modifies the implementation to insert a function pointer into the C runtime initialization instead.
PiperOrigin-RevId: 896612678
Change-Id: I07732147b955d741c836acff6da986db0e9b9eff
Yuval Tassa