Remote Actuators for micro R/C - for GIAOM 

+GrandadIsAnOldMan Glad you saw the vid. Yep, that magnet is quite nifty for what it is. Makes flying around that much easier without wondering if the foam is dangling in the wind. A neat thing too, is that it just sticks to the side by itself, then just glue it in place.

Ah no, it's fully proportional if the receiver is capable. The ItCanFly receiver on this was multi-step, increasing the deflection with increasing current. My stick wiggling in the vid likely makes it look bang/bang. Same construction for both types though :)

Sorry for the late reply. Yes, normally for actuators there can be 2x coils and use 2x outputs to switch directions. I think this used the ItCanFly circuitboard though, where only 1 coil is needed. The outputs are similar to motor control, rather than servo control.

Am glad it was of use :)

Thank you for this explanation. Can you elaborate on the electronics you used and how it works?

This R/C receiver is by 'It Can Fly', but actuators that work in a similar way are found on a lot of indoor flyers instead of servo's. They power up the coil to 1 polarity and swap it over to move the magnet in the middle in the opposite direction. If done with PWM, the coil can be controlled as a number of steps of movement in each direction. For homemade versions, the coil has to be powerful enough to move the magnet well and the magnet strong enough to move the controlled surface enough within flight. Too powerful a setup will draw more power and also often results from a coil that's too heavy or a magnet that's too big (heavy again). Too little will obv not allow the surface to move in the air enough. A balance. So, in essence, they're little electromagnets, switched on and off by using the sticks on the controller.

Thank you! I wil make a test setup I don't see how it could work proportianal yet. But we will see and learn. thanks again.

Hopefully this helps - It works proportionally by the amount of current sent to the coil. How to do that is with how much 'on' time there is of the coil, 1000 times a second. Say for example you wanted half deflection of and aileron instead of full down or full up, the receiver would send power for half the time and switch off for the other half. For 33% deflection, it would be on for 33%, off for 66%. That's what PWM is (Pulse Width Modulation), whereby the amount of time per pulse of on or off gives that width. As a stream of fast pulses, it then translates into the movement of the aileron to that amount. On an oscilloscope, it looks like a square wave, with different lengths of high and low lines, which are the power on and power off.

+bill bailey Cheers Bill. Am quite new at making these, but they've proven reliable. The 2 coils shown on the bit of foam (one just a coil, the other a full actuator) are now actually on the bi-plane lol

In this case, the receiver was intended for actuators, the ItCanFly 3 planes box set from a few years ago. One way to test is to convert a mini quadcopter circuit (Furibee F-36, Eachine E010, CX10, Santa quad etc). You can connect to the motor outputs. The coil will only deflect in one direction, but by using 2 motor outputs and 2 coils, you can have left and right. Most useful for ailerons, but, 2 conventional 400 turn coils can be wound back to back and they will result in a working rudder. Also, a lot of the 10 year old 2 channel toy planes that used 27MHz/49MHz had actuator rudders. Such planes as the Silverlit SWP. Their circuit boards can be very useful to try out actuators to make sure they work...or to replace an original coil with snapped/busted wiring with a coil of your own. Then there are Plantraco and Deltang receivers, which are also intended for actuators to connect to.

450 turns of 40AWG. It snaps easily, but makes light strong coils. Other thing, is to make sure you use a good strength of neodymium magnet...smaller pieces will save weight, but won't move the surfaces as well as larger pieces. Rule of thumb - use the biggest piece that will move in the straw (I get mine from broken HDD's and snap them up with pliers) :)

Thank you for answer .

+Raymond Earle Thanks Ray and best wishes for your recovery !

Thank you. I am getting there.