Glossary

The canonical definitions behind Rootd — used verbatim across the product, the API, and these docs. 28 terms.

Battery health & state

BaaS (Battery-as-a-Service): A model where riders pay for access to charged batteries (per swap or subscription) rather than owning them; the operator or financier retains asset ownership.
Digital twin: A vendor-neutral software model of a physical battery that aggregates its telemetry and history into a single canonical representation, independent of any BMS vendor's format.
Physics guardrails: Hard physical constraints in Rootd's SoH/SoC models that keep estimates out of impossible regions — SoH never exceeds 100%, charge in balances charge out, temperature/rate bounds respect the electrochemistry. A live violation forces a hardRetirement flag.
RUL (Remaining Useful Life): The estimated remaining service life of a battery before it falls below a usable performance threshold, derived from its SoH trajectory over time.
SoC (State of Charge): Currently available charge as a fraction of present usable capacity, a unit-interval ratio (0–1). SoC is estimated as a function of SoH and is never modeled as an independent field.
SoH (State of Health): Present usable capacity relative to original rated capacity (0–1, where 1.0 is nominal). The foundational health measure from which SoC and RUL are derived.
Swap event: A discrete transaction in which a rider exchanges a depleted battery for a charged one at a station — recorded with the batteries involved, the station, and a timestamp.
Swap friction: Any delay, unavailability, or detour a rider experiences when swapping (no charged battery in stock, queueing, traveling to a distant station) that erodes earning time.

Actors & domain

Boda-boda: An electric motorbike used for commercial passenger or delivery transport in East Africa — the primary vehicle class Rootd's operators serve.
Financier: A stakeholder who funds batteries or fleets and needs SoH-backed residual value and loan-performance visibility to manage risk.
Loan-health signal: A categorical signal on a LoanAccount — performing, watch, or impaired — comparing the asset's SoH-backed residual trajectory against outstanding principal and remaining tenor. Prolonged connectivity loss degrades it to watch regardless of last-known SoH.
Portfolio aggregate: A FinancierView roll-up across every LoanAccount within one tenant: total exposure, share by loan-health signal, and concentration by chemistry and vendor. Strictly tenant-scoped — never aggregated across operators.
Rider: The end driver of a boda-boda who depends on battery uptime and earnings retained after swap friction.
Station: A physical location where riders swap batteries and where batteries are charged and held in inventory.
Tenant / operator: A swap-network operator that is a customer of Rootd. All data and decisions are tenant-scoped; 'tenant' and 'operator' refer to the same entity.

Technical & platform

asOfTs: A timestamp on a derived value recording which state it was computed against — twin state for residual valuations, forecast state for OperatorView, ingest state for commercial terms. Lets a consumer audit a number back to its source.
BMS (Battery Management System): The on-battery hardware/firmware that monitors and protects individual cells in real time. Rootd consumes its telemetry but owns none of it.
Confidence interval: A two-sided interval expressing uncertainty on a point estimate, shaped as { lower, upper, level }. Shared verbatim across the rider-scheduling, loan-performance, and station-forecasting pillars — one calibration story for all three.
Connectivity state: A first-class status for how current telemetry is: online (fresh), stale (aging past threshold), offline (no recent contact). Decisions must account for this state — it is never an error path.
Edge / Cloud: The edge tier handles latency-sensitive, locally-scoped processing close to the battery or station; the cloud handles cross-station, fleet-wide, historical analysis. The split is decided by latency and data scope.
Hypertable: A TimescaleDB-partitioned PostgreSQL table optimized for time-series telemetry ingestion and querying at scale.
Phase A / Phase B: The two phases of residual-value calibration. Phase A calibrates against a literature-derived SoH→value curve with a visible synthetic adjustment; Phase B activates once a curated retired-pack reference has enough coverage, and the adjustment retires.
Read projection / lens: A purpose-shaped, read-only view of underlying data tailored to a stakeholder or decision (e.g. a financier residual-value lens), built from canonical data rather than mutating it.
Snapshot: The day's authoritative residual-value and loan-health computation per LoanAccount, run on a daily cadence. Reproducible across same-day reads, and distinguished from on-demand recomputes by its asOfTs.
staleAfterTs: A timestamp on a rider recommendation telling the client when to discard or re-pull it. Computed server-side from input freshness and CI width — tighter intervals and fresher twin state extend it. Honored by every client.
Supply/demand decomposition: A station forecast viewed as projected charging supply minus projected swap demand, bounded by physics guardrails. Lets operators tell a transient demand peak from a structural supply shortfall (InventoryRisk.signal: peak vs shortfall).
Synthetic-calibration adjustment: An adjustment applied during Phase A to widen residual-value confidence intervals, reflecting that ground truth is modelled rather than measured. Carried in valuation provenance; retired when Phase B activates.
Valuation provenance: The audit trail on every residual-value computation: sohSource, valuationModelVersion, asOfTs, staleSource, and (during Phase A) syntheticCalibrationAdjustment. Makes every residual interpretable.