Motion — real-time trajectory generation for CSP drives¶

Requirements for taktora’s motion-control stack. The stack is split into a pure algorithmic core (taktora-motion-core — no_std, allocation-free trajectory generation) and the executor/connector glue (taktora-motion, deferred). The deployment model is a setpoint generator feeding CiA 402 servo drives in Cyclic Synchronous Position (CSP) mode: the core produces the commanded position each cycle; the drive closes its own velocity and current loops.

The cyclic control loop runs in one real-time process per EtherCAT network (one network = one master = one cycle); axes scale inside a single AxisGroup, not across processes. iceoryx2 carries commands, telemetry, and the diverse safety monitor — never the cyclic setpoint.

This component is organised under the umbrella feature below; each capability cluster has its own page (see the toctree). The trajectory core is the first cluster.

Top-level umbrella¶

Feature: Real-time motion control FEAT_0090

status: open

is satisfied by: FEAT_0091

A soft-real-time motion-control capability layered on the taktora runtime: per-cycle, bounded, allocation-free setpoint generation for coordinated multi-axis machines (point-to-point profiles, electronic gearing, camming, flying saw), delivered to CiA 402 drives in CSP mode.

The umbrella satisfies two forces that collide in a naive motion kernel:

Motion wants expressive, stateful generators — profiles, cam tables, synchronized coupling — classically modelled with boxed trait objects and growable tables.
The taktora runtime forbids both on the hot path. No heap allocation in dispatch (REQ_0060) mandates zero heap allocation in steady-state dispatch and Bounded-time dispatch (FEAT_0017) mandates bounded-time dispatch.

The resolution is a monomorphized generator (an enum, no Box<dyn>, no vtable) over pre-provisioned fixed-capacity state, evaluated as bounded polynomial arithmetic. The umbrella decomposes into capability clusters, the first of which is the trajectory core below.

Requirements at a glance¶

Used filter:

ID	Title	Status	Satisfies
FEAT_0091	Allocation-free trajectory core	open	FEAT_0090

Allocation-free trajectory core