Cockpit SX Tutorials: Mixers
Mixers Overview
Like all computer R/C systems, the Cockpit SX supports the use of mixers. These enable a control surface to perform more than one function. Examples include V-tails, flaperons and elevons.
The Cockpit SX has a very simple and transparent way of programming mixers.
Example: Flapperons
Flaperons are an example of control surfaces which perform two functions, in this case they act as both ailerons and flaps.
- As you displace the aileron stick, the surfaces move in opposite directions.
- As you displace the flap lever, the surfaces move in the same direction.
This behaviour can be expressed in terms of two mixes to the flap servos:
- The Flap control is mixed to the flap servos
- The Aileron control is mixed to the flap servos
Fortunately choosing the correct mixer menus is easy, because the menu names follow the English description above! So, to set up flapperons, the following two mixers are used:
- F-F (Flap lever -> Flap servos)
- AI-F (Aileron stick -> Flap servos)
The system already knows which direction to drive the servos. All you have to do is to program the 'strength' of each mix. In the case of flaperons, you'd set a strong mix on the AI-F mixer, and a weak one on the F-F mixer, in order to get more aileron movement than flap. Simple isn't it?
Adjusting the Mix
The mixer menu is where you adjust the strength of the mix. All the menus work in the same way (with only a couple of exceptions) so once you have learnt one, you've learnt them all.
In the example below, the Spoiler Compensation mixer below shows 40% spoiler stick signal being mixed to the elevator servo.:
40% Spoiler Compensation
Complete List of Mixers
For a complete list of mixers, see the Mixers section in the Feature Matrix. Note that not all the mixers are available in all model types. However the GLIDER model type is the most versatile - only the DELTA mix and the Y-lead facility are missing.
Specific Applications
Sailplanes with 4 servos in the wing
The Cockpit SX has excellent support for sailplanes with 4-servo wings.
- The servos for the inner control surfaces (flaps) are connected to chs 6 and 7 and controlled by the xx-F (flap) mixers.
- The servos for the outer control surfaces (ailerons) are connected to chs 1 and 5, and controlled by the xx-AI (aileron) mixers.
There are four mixers in each set, supporting crow, snapflap, roll control and camber.
Table 1 - Mixers for wings with four servos
| Mixing Function | Mixer for ailerons (chs 1&5) |
Mixer for flap (chs 6&7) |
Notes |
| crow brakes | SP-AI | SP-F | Ailerons up, flaps down |
| elevator to flap mixing (snapflap) | EL-AI | EL-F | |
| roll control | AI-AI | AI-F | |
| camber adjustment | F-AI | F-F |
Sailplanes with 2 servos in the wing
For sailplanes with two servos in the wing, the control surfaces will normally be designated as ailerons. See the second column above.
Alternatively for some models, it may be better to to designate the surfaces as flaps (chs 6 and 7), see the third column above. See also DLG Setup.
Setting Aileron Differential
Aileron differential is adjusted in the AI-AI (Aileron stick to Aileron servos) and AI-F (Aileron stick to Flap servos) mixers. For more info see differential adjustment.
V-tail and Delta layouts
The VTail and Delta mixers are setup via special menus. Please refer to the manual.