Control modes and set‑point paths {#modes_and_setpoints}

[TOC]

Summary

How YARP control modes map to CiA‑402 operation modes and which targets are used, with brief notes on conversions.

YARP mode	CiA‑402 op (6060)	Target written	Feedback read	Notes
POSITION	1 (PP)	Target position	Position actual	Uses 0x6081/0x6083 (profile params)
POSITION_DIRECT	8 (CSP)	Target position (cyc)	Position actual	Not Implemented
VELOCITY	9 (CSV)	Target velocity	Velocity actual	Units converted to rpm on loop shaft
TORQUE	10 (CST)	Target torque	(optional) torque actual	Joint Nm → motor Nm → per‑thousand
CURRENT	10 (CST)	Target torque	(optional) torque actual	A → motor Nm via torque const → per‑thousand
IDLE / FORCE_IDLE	0	—	Statusword	Power stage disabled / reset

See protocol_map.md for exact object indices and data types.

CSV (velocity):
- velocityMove() writes the velocity target each cycle.
- Joint deg/s are transformed to rpm on the loop shaft.
- Feedback: velocity actual.
CST (torque/current):
- setRefTorque() or setRefCurrent() writes the torque target each cycle.
- Torque path: joint Nm → motor Nm → per‑thousand of rated motor torque.
- Current path: A → motor Nm via torque constant → per‑thousand.
- On CST flavor or mode change, set‑points/latches are cleared to avoid stale outputs.
PP (profile position):
- positionMove()/relativeMove() write target position on demand.
- Profile params set via ref speed/accel; completion via Statusword “target reached”.
CSP (position direct):
- Not Implemented.

Unit formulas (counts↔deg, rpm↔deg/s, Nm↔per‑thousand) and gear‑ratio/mount transforms are listed in protocol_map.md and dual_encoder_handling.md.

use_simple_pid_mode: when true the driver configures 0x2002:00 = 1 (Simple PID); when false it configures 0x2002:00 = 2 (Cascaded PID).
simple_pid_kp_nm_per_deg: joint-side proportional gain list (Nm/deg). Converted to the drive’s simple PID units [mNm/inc] using the configured encoder source and gear ratio.
simple_pid_kd_nm_s_per_deg: joint-side derivative gain list (Nm*s/deg). Converted to [mNm*s/inc] with the same transforms.
The gain keys are optional as a pair: if exactly one of the two is provided the driver returns an error.
When both gain keys are present and use_simple_pid_mode=true, the driver programs 0x2012:01/03 with the converted gains, and zeroes 0x2012:02 (Ki).
When use_simple_pid_mode=false, any simple_pid_* keys are ignored to avoid applying the simple-PID conversion rules while in cascaded PID structure.

protocol_map.md — PDO/SDO reference and conversions
dual_encoder_handling.md — encoder mounts, feedback selection, and shaft transforms