SystemID mode would not start
What ArduPilot says:
- Axis requires switch from Loiter
- Aircraft must be flying
- No axis selected, SID_AXIS = 0
- Axis requires manual throttle
SystemID mode shakes one control axis with a test signal so the copter's response can be measured; it is a tool for tuning by analysis, not a mode to fly in. It refused to start. “No axis selected, SID_AXIS = 0”: no test is chosen. “Aircraft must be flying”: it must be entered in the air. “Axis requires manual throttle”: axes 1 to 13 test the attitude loops and must be entered from Stabilize or Acro. “Axis requires switch from Loiter”: axes 14 to 19 test the position loops and must be entered from Loiter.
What to do, most likely first
SID_AXISis 0.FixSet
SID_AXISto the test you want before the flight, and read what each value shakes: the copter will move by itself.The mode was selected on the ground, or from a mode that this axis does not allow.
FixTake off, hover in Stabilize (axes 1 to 13) or Loiter (14 to 19) with room all around, then switch.
A switch or flight mode slot is set to SystemID by mistake.
CheckLook for 25 in FLTMODE1 to FLTMODE6.
FixGive that switch position the mode you meant.
Parameters to look at
| Parameter | What it is |
|---|---|
SID_AXIS | System identification axis |
SID_MAGNITUDE | System identification Chirp Magnitude |
FLTMODE1 | Flight Mode 1 |
FLTMODE2 | Flight Mode 2 |
FLTMODE3 | Flight Mode 3 |
Where to do it:Setup & Tuning Guide
The code that sends it
Axis requires switch from Loiter
ArduCopter/mode_systemid.cpp ModeSystemId::init() · Open in ArduPilot Copter-4.7.1
Aircraft must be flying
ArduCopter/mode_systemid.cpp ModeSystemId::init() · Open in ArduPilot Copter-4.7.1
No axis selected, SID_AXIS = 0
ArduCopter/mode_systemid.cpp ModeSystemId::init() · Open in ArduPilot Copter-4.7.1
Axis requires manual throttle
ArduCopter/mode_systemid.cpp ModeSystemId::init() · Open in ArduPilot Copter-4.7.1