INAV mixer: platform type, frame presets, motor and servo rules

The Platform card is the first place the aircraft type is set by hand. Platform type lists the lookup the flight controller sent. FlySpark prints those names with spaces and capitals, so MULTIROTOR appears as Multirotor. Choosing a frame preset writes the preset's platform into this same field: Multirotor, Tricopter, Airplane, Rover or Boat. Helicopter is on the demo's list and has no frame chip.

Props out (reversed motor direction) is a single toggle. The hint says every motor spins the other way and yaw is flipped to match. The frame diagram uses that flag, so the preview spins the other way while the toggle is on. Has flaps turns on the FLAPERON mode and the flaperon mixer input. Assign that mode on the Modes tab after the toggle is saved.

The link toggle follows the firmware's setting name. INAV 7 answers mixer_pid_profile_linking. INAV 8 answers mixer_control_profile_linking. A missing setting is not drawn, so a board shows one of those rows, not both. The visible label on each is Link mixer profile to control profile. Only the INAV 7 row carries the hint about switching to the control profile with the same number. The PID tuning page is where the control profile's gains live; this toggle only ties the profile numbers together.

INAV 7 and later can keep two mixer profiles. FlySpark shows the Mixer profile card only when the board reports at least two. The selected segment is the profile in use. Choosing the other one asks for confirmation. If the draft has unsaved mixer changes, the dialog says those changes will be discarded. It also says the flight controller saves its settings and reboots to set up the outputs for this profile. Confirm with Switch & reboot, or cancel. While the board is armed the segments are disabled and the line reads Disarm to switch mixer profiles.

Under the segments, the card says which profile you are editing and how many used motors and servo rules the other profile holds. A motor counts when its throttle is not zero. A servo rule counts when its rate is not zero. If MIXER PROFILE 2 is already on a switch, the card says switch off flies profile 1 and switch on flies profile 2. If it is not, the card says to put MIXER PROFILE 2 on a switch in the Modes tab.

Automatic switch on RTH, Transition time and Tailsitter orientation sit on this card, so they belong to the profile you are editing. Transition time uses a scale of 0.1 and one decimal place, with the unit seconds. The minimum and maximum come from the board's setting, not from a fixed box in the tab. Tailsitter orientation is a toggle for that profile only.

The Frame card header is the preset whose motor rules and servo rules match the current mix, or Custom mix. Tapping a chip only previews it. The diagram and the line Preview of that name stay on screen, and the rules below do not change until you press Use and confirm. Use is disabled when that preset is already set, and the button then reads that the name is set. Confirming replaces every motor and servo mixer rule and sets the platform. The dialog names the platform with the same pretty label as the Platform type menu. Nothing is written until Save. If the preset includes servos, the dialog adds a line to check that every control surface moves the right way before flying.

Multirotor chips are Quad X, Quad +, Hex X, Hex +, Y6, Y4, Octo X8, Octo Flat +, Octo Flat X, V-tail Quad, Hex H and A-tail Quad. Tricopter is its own platform. It has three motors with yaw left at zero and one servo rule: Servo 5, stabilised yaw, rate 100. Airplane chips are Flying wing, Airplane, Flying wing, differential thrust, Airplane, differential thrust, Airplane V-tail, Airplane V-tail, differential thrust, Airplane V-tail, single aileron servo, and Airplane without rudder. Boat and Rover are separate chips. Rover and Boat share the same motor and servo rules, one motor and Servo 4 on stabilised yaw at 100 percent, so the platform name is what tells them apart.

Flying wing puts stabilised roll and stabilised pitch on Servo 2 at 50 percent, and on Servo 3 at −50 percent roll and 50 percent pitch. Airplane puts stabilised pitch on Servo 2, stabilised roll on Servo 3 and Servo 4, and stabilised yaw on Servo 5, each at 100 percent. Differential-thrust airplane and wing presets add a second motor with the opposite yaw sign. The V-tail presets mix pitch and yaw onto the tail servos at 50 and −50 percent. After a preset is applied you can still edit any row, and the header becomes Custom mix as soon as the rules no longer match a chip.

The Motor mixer footer says each motor's share of throttle, roll, pitch and yaw. Roll and pitch place the motor on the frame. The sign of yaw sets which way it should spin. An empty list says No motors. Pick a frame above or add one. Add motor is available until every slot the board reported is used. The new rule is throttle 1, roll 0, pitch 0, yaw 0, which is a used motor that does not yet command roll, pitch or yaw.

The Servo mixer footer says each rule adds input times rate to a servo, and that endpoints, centre and reversing are on the Servos tab. If the board reports no servo mixer, the card says so and offers no rows. If it does, and no rule is used, the card says No servo rules. Multirotors don't need any. When any rule is used, a warning says to check on the bench that every control surface moves the right way for roll, pitch and yaw.

Applying a preset or editing a number only changes the draft. The Platform card says mixer changes apply after Save reboots the flight controller. Until that save, Motor order and Spin direction stay disabled, with the note Save your mixer changes first. After a clean save, Motor order opens the INAV motor reorder screen and Spin direction opens the motor direction wizard. Both work on the rules stored on the board, so a preview or an unsaved edit is not what they rearrange.

Switching mixer profile is a different write. It discards the draft, asks the board to select the profile, and reboots. The snackbar then names the profile that is in use. Props stay off for that reboot, the same as for any mixer save. The INAV configurator page covers connecting and the rest of the INAV tabs around this one.