gs.options.MPMOptions

class genesis.options.solvers.MPMOptions(*, dt: float | None = None, gravity: tuple | None = None, particle_size: float | None = None, grid_density: float = 64, enable_CPIC: bool = False, lower_bound: tuple = (-1.0, -1.0, 0.0), upper_bound: tuple = (1.0, 1.0, 1.0), use_sparse_grid: bool = False, leaf_block_size: int = 8)

Options configuring the MPMSolver.

Note

MPM is a hybrid lagrangian-eulerian method for simulating soft materials. In the eulerian phase, it uses a grid representation. The upper_bound and lower_bound specify the simulation domain, but a safety padding will be added to the actual grid boundary. Therefore, the actual boundary could be slightly tighter than the specified one. Note that the size of the domain affects the performance of the simulation, hence you should set it as tight as possible.

Parameters:

• dt (float, optional) – Time duration for each simulation step in seconds. If none, it will inherit from SimOptions. Defaults to None.

• gravity (tuple, optional) – Gravity force in N/kg. If none, it will inherit from SimOptions. Defaults to None.

• particle_size (float, optional) – Particle diameter in meters. If not given, we will compute particle_size based on grid_density, where particle_size will be linearly proportional to the grid cell size. A reference value is particle_size = 0.01 for grid_density = 64. Defaults to None.

• grid_density (float, optional) – Number of grid cells per meter. Defaults to 64.

• enable_CPIC (bool, optional) – Whether to enable CPIC (Compatible Particle-in-Cell) to support coupling with thin objects. Defaults to False.

• lower_bound (tuple, shape (3,), optional) – Lower bound of the simulation domain. Defaults to (-1.0, -1.0, 0.0).

• upper_bound (tuple, shape (3,), optional) – Upper bound of the simulation domain. Defaults to (1.0, 1.0, 1.0).

• use_sparse_grid (bool, optional) – This option is deprecated.

• leaf_block_size (int, optional) – This option is deprecated.