とよふく🎍Toyofuku

JUST IN: Google DeepMind just released MuJoCo 4.0. The first major version of the world’s most widely used robotics physics engine since 2023. The problem it solves is subtle but fundamental. Collision detection checks object positions only at discrete timesteps. A thin or fast object can move further than its own thickness in a single step and pass straight through another. The usual fixes are a smaller timestep or an inflated margin. Both cost you speed or accuracy. MuJoCo 4.0’s headline feature, speculative contacts, takes a different approach. Each fast-moving geom is swept forward through the step to find when it would hit something. The solver gets a contact like any other that stops the motion at the surface. No sub-stepping required. What else is new: → Deformables solved implicitly together with rigid bodies, joints and tendons, keeping cables, cloth and shells stable at 5-10x larger timesteps → Penetration-free cloth and elastic rods with bending and twist → Plasticity: wires, clay, folded paper and metal foil now keep their dents and creases → MuJoCo Studio: a new viewer SDK with physically based rendering, running in a browser tab with nothing to install → MuJoCo Playground 1.0 ships alongside The simulators are catching up with the real world! 😮‍💨 🔗 Check it out here: mujoco.org/ Congrats @carolina_parada, @yuvaltassa and team! ~~  ♻️ Join the weekly robotics newsletter, and never miss any news → ziegler.substack.com