Outputs & Motors

The Outputs / Motors tab sets the ESC/output protocol, confirms motor order and spin direction, and runs a props-off motor test. On ArduCopter it works from the frame’s motor matrix; Plane, Rover, and Sub show a read-only summary of their output assignments instead.

Everything is on one page. The motor map and the order/direction work sit top-left, the ESC and range settings below them, and the throttle sliders in a live column alongside — so setting a protocol no longer means leaving the page you were checking the result on. (The Servos tab keeps its sub-tabs; those are genuinely separate subsystems rather than three views of one job.)

Warning

Props off for everything on this page. Remove all propellers before any motor test, order check, or direction check, and restrain the vehicle with the area clear. Treat a connected, powered vehicle as if it could spin a motor at any moment — the test arms the autopilot to do exactly that. The run button stays disabled until you confirm props are off and the area is clear.

ESC & protocol

The ESC & Protocol panel sets the frame (FRAME_CLASS / FRAME_TYPE) and the output protocol, MOT_PWM_TYPE:

  • 0 Normal, 1 OneShot, 2 OneShot125, 3 Brushed

  • 4 DShot150, 5 DShot300, 6 DShot600, 7 DShot1200

  • 8 PWMRange

DShot ESCs can also report RPM back over bidirectional DShot (bdshot), configured with SERVO_BLH_BDMASK (the per-output telemetry mask) alongside SERVO_BLH_AUTO. Frame class/type and MOT_PWM_TYPE are reboot-required.

Note

Bidirectional DShot is a compile-time firmware feature. If SERVO_BLH_BDMASK isn’t present in the synced parameters, your firmware build doesn’t include bdshot support — and most boards that do support it only offer it on the first four (sometimes eight) outputs.

Motor order & direction

The Motor Setup panel carries the reorder work inline, with an Order tab and a Direction tab (both gated behind the props-off acknowledgement — one acknowledgement at the top of the page covers everything on it):

  • Order — Identify motors interactively spins each output briefly (about 2.5 s at 6%) and you click the position on the schematic that moved, which stages the SERVOn_FUNCTION mapping. Apply stages a reboot.

  • Direction — click a motor to spin it and compare against the arrows (top-view CW/CCW); a per-motor Reverse toggle flips its spin via SERVO_BLH_RVMASK. Reverse toggles are only available on a DShot protocol (MOT_PWM_TYPE 4–7); on PWM ESCs you reverse a motor by swapping any two of its three ESC wires.

Note

The schematic draws the real layout for your frame. It reads FRAME_CLASS / FRAME_TYPE and renders that frame’s actual motor positions and per-motor spin directions from ArduPilot’s motor matrix — so an H-frame reads as an H, a hexa shows six arms, a Y6 shows its coaxial stacks, and so on, rather than always drawing a quad-X. Each motor’s spin arrow curves above (front) or below (rear) its ring in the correct CW/CCW direction. Still confirm each motor physically spins the way its arrow shows before flying.

Motor test (props off)

The Test column spins motors at a set throttle for a set time. Pick a single output, all motors in sequence, or all at once; set Throttle % (1–100) and Duration (up to 5 s, 30 s in Expert mode). The throttle can be dragged on the slider or typed into the percent box beside it — a slider is the fast way to find roughly the right throttle and a poor way to ask for exactly 7%, which is what a repeatable bench test wants. It sends MAV_CMD_DO_MOTOR_TEST and is gated by eligibility checks — the vehicle must be connected, disarmed, parameter-synced, with no other guided action running — plus the physical-safety acknowledgements. There’s no “test finished” message from the firmware, so the per-motor timeout on the autopilot is the hard safety net.

Warning

When testing over USB on the bench, the app asks for an extra acknowledgement. Never run a motor test with props on, and confirm each numbered motor is the one that actually spins before trusting the layout.

Spin thresholds (Expert)

MOT_SPIN_ARM and MOT_SPIN_MIN decide where your motors start turning and where thrust begins. ArduPilot’s defaults — 0.10 and 0.15 — were never measured against any particular build, and where a motor actually breaks away is a property of that ESC and that motor. Too low and a motor may not start on arming; too high and it lurches.

In Expert mode the Motor Setup panel offers Measure Spin Thresholds, which opens a popout that measures it instead of guessing:

  1. Every motor is driven together at a rising output, starting at 0.01.

  2. The motors stay live and follow the slider — raise it slowly until they all just break away. (This is why it is a measurement, not a sample: you are looking for the edge.)

  3. Press They just started spinning. MOT_SPIN_ARM lands one 0.03 margin above that point, and MOT_SPIN_MIN another 0.03 above ARM — the ordering the firmware requires.

  4. Both values stay editable, and are staged for you to apply. Nothing is written by the wizard.

The slider covers MOT_SPIN_ARM’s own 0–0.20 range rather than a full 0–100% throttle, so a single 1% step is a real amount of travel.

Warning

The wizard spins every motor at once, so the props-off acknowledgement gates it exactly like the motor test. Closing the popout stops whatever it was spinning, and each command carries a short timeout that acts as a deadman: if the browser stops sending — tab closed, page crashed, link dropped — the motors stop on their own without anyone pressing anything.

Note

ArduPilot refuses to arm when MOT_SPIN_ARM is greater than or equal to MOT_SPIN_MIN. The wizard cannot produce such a pair, and if you edit the values by hand it says so before you can stage them.

See also Ports & Serial for ESC telemetry input and Power & Battery for the battery monitor. For motor-order diagrams, ESC wiring, and spin-direction testing, see the ArduPilot wiki: Connect ESCs and Motors.