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…trol - Swap car body XY dims so car faces +X (longer) instead of +Y (wider) - Lower car body (z=0.22) and wheels (rel z=-0.1) so wheels touch ground - Replace axisangle body rotation with fromto on cylinder geoms for correct wheel orientation - Change actuator_force to ctrl so motor control signals aren't overwritten by mj_step - Add camera marker spheres (topdown red, firstperson green) - Adjust firstperson camera pos/fovy for forward-facing view
…ree.js Replace backend MuJoCo (Python + JPEG streaming) with browser-native simulation using @mujoco/mujoco WASM bindings and Three.js rendering, enabling multi-user independent training. Fix React StrictMode duplicate canvas rendering issue.
…rientation axes gizmo - Add WASD/Arrow keyboard controls for driving the car - Add first-person camera overlay in bottom-right corner - Add orientation axes gizmo in bottom-left corner - Simplify car model to wheels + chassis, remove robotic arm - Add wheel spoke geometry for visible rotation - Fix setControl to use manual actuator name resolution - Add multi-substep physics (16 substeps per frame) - Clean up debug logging
…es gizmo The mjToThree quaternion maps MuJoCo body orientation correctly for geoms but not for cameras — it mapped the camera's look direction to the wrong axis. Compute look/up vectors explicitly and use camera.lookAt() instead. Also add X/Y/Z text sprites at the tips of the orientation axes gizmo.
…ntation - Reduce SUBSTEPS from 16 to 5 for slower, more stable physics - Fix axes gizmo labels: Z (blue) on vertical, Y (green) on horizontal to match MuJoCo coordinate system (X=forward, Y=left, Z=up) - Correct first-person camera euler to "90 -90 0" so it looks forward (+X) instead of toward ceiling - Add debug logging for car ctrl, wheel velocities, yaw, and quaternion - Adjust camera visual indicator geom direction
…non-wheel cylinders - Wrap camera, box, and cylinder in camera_body so they move as one unit - Only add cross-spokes to wheel-like cylinders (radius >= halfHeight) to avoid artifacts on thin indicator cylinders
- Render hinge joint axes as red cylinders in 3D scene using d.jnt() accessor - Add "Show Joints" checkbox in ControlPanel to toggle overlay visibility - Fix wheel hinge axis to Y (0 1 0) for correct forward motion - Clean up legacy debug logging from animation loop
… axis with MuJoCo Z axis Three.js CylinderGeometry extends along Y by default, but MuJoCo cylinder geom local Z is the axis direction. Compose a +90° X-axis pre-rotation quaternion in the animation loop for all cylinder-type geoms so their visual axis matches the physics orientation.
T * R * Tinv mapped MuJoCo Rz(+θ) (left turn) to Three.js Ry(+θ) (right turn), causing car body and wheels to rotate in opposite directions. Fix to Tinv * R * T, which correctly maps to Ry(-θ) (left turn). Removes all cylinder-specific quaternion adjustments and geomTypesRef as they are no longer needed.
- Replace mjToThree formula with direct axis extraction from geom_xmat and makeBasis(gx, -gz, gy) for proper rotation (det=+1) - Fix cam_xmat column indexing: look direction = column 2 (Z axis), up vector = column 1 (Y axis), not row-major indices - Detect fromto cylinders by comparing position with same-body geoms, compute correct cylinder axis direction from midpoint offset - Track geom types via geomTypesRef for cylinder-specific handling
Replace flat geom-xpos/xmat placement with standard body hierarchy: - Each MuJoCo body -> THREE.Group, parented by m.body_parentid - Geom meshes as children of body groups with LOCAL pos/quat from m.geom_pos / m.geom_quat (includes fromto and euler) - Body world transforms updated from d.xpos / d.xquat each frame - Add mjPosToThree / mjQuatToThree coordinate conversion helpers - Remove obsolete mjToThree, makeBasis, fromto detection, geomTypesRef Net: -92/+46 lines, no special-case geom orientation code needed
d.xpos is world position, so all body groups must be direct children of world (body 0) to avoid double-applying parent transforms. Matches muwanx approach: bodyGroups[b].add(mesh) for geoms, but all body groups added to world group.
- Ground + wheel friction: 1.5/0.005/0.0001 (more grip, less roll) - Freejoint damping: 0.5 (prevent oscillation) - Motor gear: 5→3, ctrlrange: ±10→±5 (reduce torque, prevent wheelies)
- Ground friction: 1.5/0.005/0.0001 - Wheel friction: 1.5/0.005/0.0001 - Freejoint damping: 0.5
freejoint does not support damping in MuJoCo. Only friction changes remain.
- 8x8 maze with 2m corridors, box geom walls - Car starts at safe position (3, -3) - Removed contype/conaffinity=0 from car body for collision - Ground plane expanded to 100x100
- mazeXml.ts: ground plane + maze walls (independently editable)
- carArmXml.ts: imports MAZE_XML and composes car + camera + actuators
- Combined at runtime via template literal ${MAZE_XML}
- Remove non-existent motor_yaw/pitch/roll sliders - Remove redundant wheel sliders (WASD handles driving) - Add Drive Speed and Turn Speed sliders with real-time effect - Keep Reset and Show Joints toggle
- Replace fake '60' FPS with real requestAnimationFrame counter - Use capture:true on keydown to intercept before browser scrolls - Add Space to blocked keys list + brake functionality - Add stopPropagation for reliable event capture
- Wheel hinge joints: damping=1.5 (natural slowdown when releasing throttle) - Ground plane friction: 1.5→2.5 (less sliding in turns)
…tter driving feel
…kthrough - Add docs/src/MuJoCo/No_5.md covering FSM controller, cubic polynomial trajectory, PD tracking, and ctrl channel mapping - Update SUMMARY.md to include No.5 entry - Fix no_5.py: load doublependulum_fsm.xml (not .py) and add 1ms frame pacing - Fix doublependulum_fsm.xml: remove deprecated sensornoise flag attribute
…ough - Add docs/src/MuJoCo/No_7.md covering state-space formulation, numerical linearization, LQR design (CARE solver), and noise-injection robustness test - Update SUMMARY.md to include No.6 and No.7 entries (No.6 was missing) - Fix doublependulum.xml: remove deprecated sensornoise flag attribute
…an walkthrough - Add docs/src/MuJoCo/No_6.md covering IK control, Jacobian inverse, site/framepos sensor, and position servo - Track previously untracked No.6 source files (XML + Python)
…h FSM walkthrough - Add docs/src/MuJoCo/No_8.md covering connect equality, efc_J/efc_force, force-handoff trick, and FSM release - Update SUMMARY.md to include No.8 entry - Fix hybrid_pendulum.py: reshape efc_J from 1D to 2D (MuJoCo 3.x API change) - Track No.8 source files (XML + minimal no_8.py + full hybrid_pendulum.py)
…with full walkthrough - Add docs/src/MuJoCo/No_9.md covering Raibert hopper 4-state FSM, runtime actuator_gainprm modification, foot/torso state detection, and elastic energy storage/release pattern - Update SUMMARY.md to include No.9 entry - Track No.9 source files (hopper.py + hopper.xml)
…) example - Add docs/src/MuJoCo/No_11.md covering offline trajectory optimization, COBYLA solver, simulator-as-constraint-evaluator pattern, and open-loop playback - Update SUMMARY.md to include No.11 entry - Track No.11 source files (ball.xml + projectile_opt.py)
- Add docs/src/MuJoCo/No_12.md covering NLopt-based numerical IK, Lemniscate of Bernoulli trajectory, separate data_sim for FK, and matplotlib trajectory comparison - Update SUMMARY.md to include No.12 entry - Track No.12 source files (manipulator.xml + manipulator_ik.py) - Document 3 bugs in original code: duplicate forward_kinematics function, dead ctrl setting, commented-out set_mjcb_control
…+ ramp gravity) example - Add docs/src/MuJoCo/No_13.md covering parallel FSM coordination (hip + knee1 + knee2), quat2euler state estimation, tilted gravity for ramp walking, and joint frame visualization - Update SUMMARY.md to include No.13 entry - Track No.13 source files (biped.py + biped.xml) - Document 3 bugs: unused 'pin' joint, suspicious init_controller assignment, hardcoded body indices
- Add 4-DOF arm to car.xml: shoulder_pan, shoulder_lift, elbow, wrist_pitch + gripper (slide) - Add 5 position servos for arm (kp=30-100, kv=3-10) - Add armature=0.05 + damping=0.5 to arm joints for numerical stability - Create walker.py with GLFW keyboard control: - WASD: differential drive (left/right wheels) - Space: brake - 1-5: select arm joint, Up/Down: adjust - G: toggle gripper, 0: home pose - Backspace: reset simulation - Camera follows car position - Verify: arm reaches stable home pose (no NaN, qvel → 0 within 2s)
…lation - car.xml: bump gravity to -15, add 3-point studio lighting, and add a fixed pedestal + free-jointed target_box at world (1.5, 0, 0.45) for the M2 mobile-manipulation task. - auto_sim.py: keyboard-less 9-state FSM runner (DRIVE_TO_TARGET → REACH → LOWER → GRASP → LIFT → DRIVE_BACK → PLACE → RELEASE → DONE) using 2-link IK, position servos, and data.xpos for arm_base/target state estimation. Run with: mjpython auto_sim.py.
…ata logging, and fix joint range/lit - Add auto_sim_v2.py with numerical Jacobian 3D IK, P-controlled driving, active braking, mouse camera callbacks, FSM safety timeouts, weld grasp, and matplotlib data logging - Fix car.xml arm joint ranges from degrees to proper radian-equivalent degrees (1.57 -> 90, 2.0 -> 115) — arm was locked at ~1.6 range - Increase position servo kp/kv (50/5 -> 200/10) for faster arm response - Replace asymmetric 3-point shadowed lighting with balanced 5-point shadow-free lighting; add headlight diffuse/specular
…and-place + data collection - Add demo_collect.py: single-file MuJoCo demo exercising all 12 course concepts (model loading, GLFW pipeline, position servos, dynamics extraction, FSM, cubic trajectories, Jacobian IK, state-feedback, constraint management, contact triggers, numerical IK, separate FK, quaternion estimation) - Auto pick-and-place FSM (9 states) with multi-episode data collection to .npz - Scale arm 2x (1.06m reach), widen all joint ranges to ±150°/±180° - Remove pedestal — box now on ground for easier reaching - Remove first-person camera body from model - Delete redundant files (auto_sim.py, auto_sim_v2.py, walker.py, test.py) - Add episodes/.gitignore for collected data, fix root .gitignore
…uning - Replace single-box gripper with parallel two-finger gripper (palm + 2 sliding fingers) - Add 28-channel sensor suite: joint pos/vel ×10, EE pos/vel, finger touch - Expand arm joint ranges to ±360° for full rotation - Sync Q_MIN/Q_MAX in demo_collect.py to match - Fix ground friction (2.5/1.0/0.001) and wheel damping (0.5) - Add site + sensor demo (pendulum) in mujoco/demo/ - Fix demo pendulum: joint name for jointvel sensor, initial push, correct euler - Log sensordata in collected .npz files
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