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View Full Version : MGL Autopilot servos - state of development


Rainier Lamers
03-26-2010, 08:59 AM
Well, it's been a while. Those that are flying our autopilot will have noticed the entries in the autopilot setup of our EFIS systems refering to the "MGL Servo".

I am happy to report - they are flying !
What is a "MGL Servo" ? It is a stepper motor based servo, very similar to those from Dynon and Trutrak in overall shape, but with a CNC machined aluminium housing that is a bit thicker (about the same as the higher torque versions of other makes). We are likely to offer three different versions which differ only in achievable torque. This is where similarity stops.
It's fully self contained, all electronics is built in. It's claim to fame is a standard, built in method to measure the actual force acting on the servo output shaft. This way we can measure actual aircraft trim without having to guess it by looking at past actions (this does not work well in turbulence - where outside forces act on the aircraft).
So, the servo goes something like: "Hmmm, stick getting a bit heavy - tell the pilot to trim a bit nose up - ah, that's better...". Of course, that info can also be used to control a trim motor directly and the servo, conveniently, has the required motor driver for this in as well.
Further to this the servo is not limited to range of movement (more than 360 degrees is possible, no limit). Position feedback is highly accurate, repeatable and - best of all - completely contactless, no wear whatsoever. To support high axial loads, the output shaft is supported by two ball bearings. We do not use any bushes. Gears are generously over-dimensioned.

Where are we ?
Development and flight testing complete. We are now making 50 of them for an extended field test on various aircraft types. After this, we are putting them in full production.
Price ? Of course it's good. We are MGL remember ?

We continue the support for Trio Servos. This means you can choose between a clutched DC motor servo or a stepper motor based servo and you can even mix.

Rainier
CEO MGL Avionics

pierre smith
03-26-2010, 09:08 AM
...and half a world away!

Thanks,

GSchuld
03-28-2010, 05:00 PM
That's great news. Could you let us in on the new servo's weight and overall dimensions(that would be appropriate for RVs or similar aircraft).

George

Rainier Lamers
03-29-2010, 12:46 AM
That's great news. Could you let us in on the new servo's weight and overall dimensions(that would be appropriate for RVs or similar aircraft).

George

Weights are very similar to other servos as the weight is determined mainly by the size of the stepper motor.
Mechanical dimensions are similar as well (same overall sizes, same mounting holes).
The servo has additional threaded mounting holes on the sides which makes it possible to mount the servo in many installations without needing a bracket.

Mechanical drawings are not ready yet but as soon as they are I will put them on the website.

Rainier

rracer10
05-20-2010, 06:31 AM
Rainier,
It's been a couple of months since your last update. Have you been field testing the AP ? How is it going and how close to production are you?

aerhed
05-20-2010, 09:33 AM
Hey, I thought you were gonna fix the conomy first.

Rainier Lamers
05-20-2010, 10:09 AM
Rainier,
It's been a couple of months since your last update. Have you been field testing the AP ? How is it going and how close to production are you?

Yes, in fact I have been flying every day for the last week. Gotta love this job sometimes.

We are ready to produce a small batch of about 50 to 100 but those are intended exclusively for field testing in various aircraft.
Currently we have about half a dozen of them with various sized motors (to cover three torque ranges). These are being tested in flight and are also being tested to destruction (they run continously lifting heavy weights) so we can get a good idea on wear of the various parts.
We have been using a steel pinion gear and a nylon main gear but it looks like we don't like the wear on the nylon gear (at least for the heavy duty servo). Also it looks like nylon has an interesting life of its own as we are discovering.
Anyway, looks like we will end up using vesconite gears, bit more pricey but I want those things to last forever. We are having some cut now and will be testing them. This is the only outstanding issue, once I am happy with the wear we will go for the first batch, then put those in a couple of aircraft and if that looks good, we will start the music.

Rainier
CEO MGL Avionics