Assumed Item

SEooC item-level scope. The integrator’s real item must be confirmed against this description (AOU_0006).

The assumed item is a taktora-hosted safety-critical periodic control application running on a single multi-core SoC under a POSIX-compliant operating system. The item performs cyclic input acquisition, control computation, and actuation via field-bus (EtherCAT) and/or pub/sub (Zenoh) connectors at a cycle rate in the range 1–100 ms. Taktora provides the execution framework (taktora-executor) and the I/O substrate (taktora-connector-*).

In scope (taktora’s responsibility)

  • Deterministic execution of registered items at declared triggers (intervals, channel arrivals, request/response).

  • Bounded memory allocation (taktora-bounded-alloc).

  • Spatial Freedom From Interference between safety-critical items and QM-grade items co-hosted in the same workspace.

  • Detection and propagation of internal framework faults — allocator exhaustion, missed deadlines, connector disconnect, item panic, channel corruption — via the ConnectorHealth channel.

Out of scope (→ becomes Assumption of Use on the integrator)

  • Correctness of the safety-critical control algorithm.

  • Functional safety of the host OS, libc, hardware (CPU, RAM, clock, power).

  • CPU / RAM / clock / power fault containment.

  • Temporal Freedom From Interference enforcement (scheduling class, CPU pinning).

  • The diverse monitoring path required by the ASIL D = B(D) + B(D) decomposition (see ASIL Decomposition).

  • Reaction to safety-goal violations escalated by taktora — taktora raises HealthEvent::Faulted; it does not define what safe state means for any particular application.