RigidSolver#

RigidSolver 用于处理刚体动力学仿真，包括铰接体、机器人和刚体对象。

概述#

RigidSolver 实现了以下功能：

  • Forward dynamics (正向动力学): Compute accelerations from forces/torques (从力/力矩计算加速度)

  • Collision detection (碰撞检测): GJK, MPR, and support function methods (GJK、MPR 和支持函数方法)

  • Contact resolution (接触解析): Impulse-based or iterative constraint solving (基于冲量或迭代约束求解)

  • Joint constraints (关节约束): Revolute (旋转), prismatic (移动), ball (球), free joints (自由关节)

  • Articulated bodies (铰接体): Multi-body tree structures (URDF, MJCF) (多体树结构)

使用方法#

import genesis as gs

gs.init()
scene = gs.Scene(
    rigid_options=gs.options.RigidOptions(
        enable_collision=True,
        enable_joint_limit=True,
        constraint_solver=gs.constraint_solver.Newton,
    ),
)

# Add rigid entities
plane = scene.add_entity(gs.morphs.Plane())
robot = scene.add_entity(gs.morphs.URDF(file="robot.urdf"))
box = scene.add_entity(gs.morphs.Box(pos=(0, 0, 1)))

scene.build()

# Control robot
robot.set_dofs_position(target_positions)
robot.set_dofs_velocity(target_velocities)

for i in range(1000):
    scene.step()

配置#

RigidOptions 中的关键选项：

Option

Type

Description

enable_collision

bool

Enable collision detection (启用碰撞检测)

enable_joint_limit

bool

Enforce joint limits (强制执行关节限制)

constraint_solver

enum

Solver type (CG, Newton) (求解器类型)

max_contact_per_geom

int

Maximum contacts per geometry (每个几何体的最大接触数)

contact_resolve_eps

float

Contact resolution tolerance (接触解析容差)

碰撞检测#

RigidSolver 支持多种碰撞检测方法：

  • GJK (Gilbert-Johnson-Keerthi): General convex collision (通用凸体碰撞)

  • MPR (Minkowski Portal Refinement): Penetration depth (穿透深度)

  • Primitives (基本体): Optimized sphere, box, capsule collisions (优化的球体、盒体、胶囊体碰撞)

接触解析#

两种主要方法：

  1. Impulse-based (基于冲量): Direct velocity update (直接速度更新)

  2. Constraint solving (约束求解): Iterative optimization (CG, Newton) (迭代优化)

# Use Newton solver for better convergence
rigid_options = gs.options.RigidOptions(
    constraint_solver=gs.constraint_solver.Newton,
    iterations=10,
)

另请参阅#