Grammar Problems#

Grammar problems describe discrete design actions over a library-owned state. Generic grammar-family tooling should use the shared GrammarProblem contract: initial_state(), enumerate_transitions(), enumerate_next_states(), and evaluate(). Concrete rule methods remain problem-specific conveniences.

See Grammar Problem Catalog for the generated per-problem catalog pages. For battery electronics/thermal modeling assumptions shared across grammar and optimization tiers, see Battery Ladder Technical Notes.

The catalog includes planar_truss_span, which translates a serializable planar topology state into a fresh trussme.Truss for evaluation. It also includes space_truss_span, which applies the same evaluation pattern to a bounded 3D space-truss state. The tiered battery grammar ladder includes battery_18650_t1_rectangular_surrogate_grammar, battery_18650_t2_pose_surrogate_grammar, battery_18650_t3a_topology_surrogate_grammar, battery_18650_t3b_netlist_explicit_2rc_grammar, battery_18650_t3b_netlist_explicit_grammar, and battery_18650_t4_thermal_hybrid_grammar. Together they expose a paired battery ladder with clear representation/fidelity labels:

  • The canonical pack compatibility matrix and the meaning of native, projected, and promoted live in Battery Ladder Technical Notes.

  • Tier 1: rectangular pack-sizing actions scored with an analytic surrogate.

  • Tier 2: pose-aware layout actions scored with analytic, promoted explicit, or promoted hybrid evaluators.

  • Tier 3A: topology-allocation actions that can be benchmarked as either an analytic surrogate, a projected explicit-circuit evaluation, or a promoted hybrid-thermal evaluation.

  • Tier 3B: explicit netlist-synthesis actions scored directly by the shared explicit-circuit backend or by promoted hybrid thermal scoring.

  • Tier 4: thermal-topology actions with analytic, explicit-circuit, or hybrid-thermal scoring.

The catalog also includes battery_18650_t3b_netlist_explicit_2rc_grammar, a manifest-backed backend-config example that keeps the tier-3B explicit-netlist grammar contract while pinning parameters.battery_backend to the shared pybamm_ecm_2rc + Marquis2019 + isothermal configuration.

The catalog also includes six planar_roof_truss_* variants that approximate the planar roof truss formulations discussed by Shea and Cagan, including multi-load and symmetry-constrained cases. The catalog also includes iot_home_cooling_system_design, which uses a typed state of IoT products and links over a fixed house geometry and reports total_cost, peak_temp_c, capital_cost, and operation_cost from a deterministic MATLAB-parity thermal and cost simulation. The catalog also includes truss_analysis_program_design, a direct port of the MATLAB Truss Analysis Program mechanics with discrete joint/member/load edits and deterministic mass_kg plus min_fos structural evaluation.

Optional evaluators:

  • The base install supports generic grammar transitions and analytic-surrogate battery paths without trussme or PyBaMM.

  • trussme is optional for the base install, available through the grammar extra, and required for real planar and 3D truss structural evaluation.

  • PyBaMM is optional for the base install and available through the battery extra. It is required when a study selects a PyBaMM-backed battery-fidelity mode.

  • Optional/full CI installs PyBaMM for battery-fidelity verification.