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Inverse Dynamics L1-449

RoboticsRobot dynamicsδ=3 · standardL_DAG = 2.8📋 Stub — not mineable
📋

Unclaimed Principle — open for contribution

This Principle is declared in the catalog but has no reference solver, no pinned dataset, and is not registered on-chain. There is no reward pool. Submitting a cert against this Principle today will record the cert for reproducibility but pay zero PWM.

To claim it as a Bounty #7 contribution: open a PR adding (1) a reference solver, (2) ≥1 dataset pinned to IPFS, (3) updates to the L3 manifest with dataset CIDs. After verifier-agent triple-review, the founders' 3-of-5 multisig signs PWMRegistry.register() and the Principle becomes mineable.

Forward model E

Inverse Dynamics: Inverse dynamics: compute joint torques required to achieve desired trajectory; used for computed torque control and parameter identification. The forward operator produces the measurement through a 3-node primitive DAG (M.rnea.recursive_newton_euler…); recovery is posed as a linear_inverse problem. Difficulty tier delta=3 with effective condition number kappa_eff~50; acceleration_estimation_noise, friction_unmodeled_dynamics set the accuracy floor at the Omega boundary. See the forward_model field for the closed-form equation.

L-DAG

D.time -> S.regressor.inertia_parameters -> O.least_squares.param_id
D.timeS.regressor.inertia_parametersO.least_squares.param_id

Well-posedness W

Existence:
true
Uniqueness:
true
Stability:
conditional
κ:
1000

Existence of the recovered joint_torque_vector is guaranteed within the declared Omega bounds. Uniqueness holds on the measurement-supported subspace; out-of-support modes are controlled by declared priors. Stability is conditionally stable (kappa_eff ~= 50); acceleration_estimation_noise dominates the stability cliff; the remaining mismatch parameters contribute higher-order bias terms. Gaussian sets the irreducible data-fidelity floor.

Solvability C

Solver class:
classical [RNEA_closed_form or LS_parameter_identification (Gautier)]
Convergence rate q:
2
Complexity:
O(n) for RNEA; O(N_traj * n_theta ** 2) for parameter ID per iteration

Specs (0)

No L2 specs registered yet for this principle.