Expand description
Stage C — time-parameterise a joint path at constant TCP speed.
This is a CNC-style constant-feedrate planner, not a TOPP retimer. The
feasible-speed ceiling along the path (the “maximum velocity curve”) comes from
the per-joint v/a/j limits projected onto the path tangent q'(s). The
commanded speed tcp_speed is held flat wherever that ceiling allows; near a
singularity |q'(s)| → ∞ so the ceiling collapses and the feedrate dips to zero
smoothly instead of demanding infinite joint speed. The profile is built by a
backward+forward acceleration-bounded pass (zero speed at both ends) followed by
a forward jerk-limited time integration that tracks it.
Joint velocity is enforced exactly; acceleration and jerk are enforced through
the tangent projection — the q''(s)·ṡ² curvature cross-term is a deliberate
first-pass approximation, softened by the jerk-limited integrator.
Structs§
- Constant
Speed Retimer - Constant-feedrate, jerk-limited retimer over a joint path.