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Documentation index and glossary

Document What it is
plan.md Phases, their pass checks and the repository’s planned layout
roadmap.md Where each phase stands, open items, skills planned beyond walking
requirements.md What the robot must and should do
decisions.md Every design decision, newest first, with reasons and alternatives (older entries describe the design as it was then)
safety.md Safety rules for benches, batteries and walking tests
design/concept.md The v0.2 concept (historical)
design/stairs.md Stair climbing: status, open issues and options
design/assembly_wiring.md Modules, assembly order, power and wiring
../sim/isaaclab/README.md Training the walking and stair policies, and every run’s results
../sim/motion/README.md The motion-tracking pipeline
../bench/README.md Actuator bench tests (phase 2)
../bom/README.md Bill of materials and how its prices are sourced
  • DOF: degree of freedom, one powered joint axis. Marvin Bot has 27, plus 8 in each hand.
  • QDD (quasi-direct drive): an actuator with a low gear ratio (about 9:1 here), so it can be back-driven and sense force through its current.
  • RobStride RS00/RS10P/RS03/RS04: the actuator models used, from small (wrist) to large (hips, knees).
  • URDF, MJCF, USD: robot description formats: URDF is generated here from description/; MuJoCo reads URDF or MJCF; Isaac Sim uses USD.
  • Code-CAD: parts written as Python code (cad/) instead of drawn in a CAD program, so they regenerate from the description.
  • SF (safety factor): yield strength divided by the calculated stress; the strength check targets 2.
  • Rated vs peak torque: a motor can hold its rated torque continuously; peak torque only briefly. RMS torque over a motion is compared with the rated value for heat.
  • CoM: centre of mass.
  • IMU: inertial measurement unit (gyro and accelerometer) in the pelvis.
  • BMS: battery management system.
  • CAN: the bus the actuators are commanded over.
  • PPO: the reinforcement-learning algorithm used to train the walking policies.
  • Policy: the trained neural network that turns sensor readings into joint targets.
  • Flat v7, rough v9: the 7th flat-ground and 9th rough-terrain training runs; each resumed the one before after a change.
  • Sim-to-real: making a policy trained in simulation work on the real robot.
  • Cross-check: replaying a policy trained in Isaac Lab in a second simulator (MuJoCo) to catch simulator-specific tricks.
  • Motion tracking (BeyondMimic): training a policy to follow a reference motion, such as a retargeted human walk.
  • Retargeting: converting a human motion to the robot’s body and joints.
  • VLA: vision-language-action model (GR00T N1.7 here), which turns camera images and an instruction into arm motions.

This page is generated from docs/README.md in the repository.