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My New Cyclic Build with Magnetic Brake Trim


molevitch

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Youtube fix

 

This is looking to be quite awesome.

 

For youtube only use the last bit of the URL. (YOUTUBE)-gYiSBwy0t0(/YOUTUBE) as an example, but with the correct [ ] brackets.

 

Hi Vladinsky,

 

Thanks for that! I will pass it on to Trip who had a similar problem.... Mine is working now, I think.

 

M

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Magnetic Brake update.

 

I made my first flight test with my mag brake setup. Its F?*%ing AMAZING! The finest controls never before possible. Blows away MSFFB completely. No centre/deadzone slop, no aggressive kick-back. I have a little bit of fine tuning to do, but really, this is trimming like it should be. I can pretty much hover with hands off! The Gazelle has suddenly become a machine that can be controlled with EASE!. Haven't yet tried the Huey, but the Hip is a joy, hover over sling loads so ground crew attach, NO PROBLEM.

 

attachment.php?attachmentid=165277&stc=1&d=1499001606

 

Basically its like a powerful centring spring joystick, but you decide where to put the centre. Miniscule fine control movements are possible because of the hard springs. You use trimmer a lot more but also for cruising its like, set it, let go, put your feet up!

 

And I am adding a handbrake....

 

attachment.php?attachmentid=165278&stc=1&d=1499001615

 

I also am now using a set of BRD Kamov pedals. I decided to buy them since I was pretty much expecting to be trying to build an almost identical set. With parts and materials, and wastage, I figured Baur's kit was the more cost effective option. And they come with the logic board too. And are stunning....

 

So on to the collective. I will be adding a mag brake to this too. Why not? I need to customise a couple of PTM buttons and add a DPDT toggle switch too. Going to use Halls for the throttle and pitch. Nearly done.

 

There will be lots of spare button slots on my Bodnar board, so I am planning a handy button box as well. No hurry though....

 

I am seriously impressed with the mag brake result! It feels like I believe a real chopper feels from what I have read, and from studying the force gradient mechanisms I can find. I hope somehow to get feedback from a real pilot, but right now I don't know any!

IMG_5334.thumb.JPG.d0d8848a932930023bee3334d3f36d59.JPG

IMG_5335.thumb.JPG.1b3a8966d7d5d4ee410cf346d133fe25.JPG

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Magnetic Brake Force Gradient Linkage

 

Mole can you get me a picture showing the detail of the linkage for the Force Trim units? I just want to see how you put it together.

 

Trip

 

Hi Trip,

 

Its tricky now to take a picture without disassembling the seat. But here is a little video, and some earlier pics will follow with some Photoshopped additions which I hope will clarify the principle.

 

 

M

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Some pics of linkage

 

Basically the cyclic, when pushed left or right, pushes or pulls on a triangle of 6mm aluminium. The pic is to give a rough idea of the principle.

 

attachment.php?attachmentid=165364&stc=1&d=1499207606

 

Hope that makes sense...

1518729092_m-24cyclicgradientlinkage01.thumb.jpg.4216cf69045540a614ba678b7da23a26.jpg

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

bsd sig 2021.jpg

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Basically the cyclic, when pushed left or right, pushes or pulls on a triangle of 6mm aluminium. The pic is to give a rough idea of the principle.

 

attachment.php?attachmentid=165364&stc=1&d=1499207606

 

Hope that makes sense...

 

Love this thread, the build is great. The little triangle thing you highlighted in red is known as a bellcrank btw, pretty common to find in real aircraft linkage for the same reasons, to transmit mechanical forces around corners/obstacles/at angles. http://richshangar.com/wp-content/uploads/2012/09/Outer-Aileron-Bellcrank-and-Push-Rods.jpg

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Hi Thadiun,

 

Yes, that's right, "bell-crank". I once lived in an large old Victorian house, and one time while doing some work in the roof space, found a whole series of old bell-cranks and wires which would have been used to summon servants to various rooms in the house. This is where the name "bell-crank" comes from.

 

attachment.php?attachmentid=165369&stc=1&d=1499235725

 

I am using one similarly on my collective which will use my third damper piston and electro-magnet to dampen the movement of the collective lever and also be a magnetic brake. That has been a more complicated journey, as there is the throttle to deal with too, and I am trying to keep it neat, simple and also "authentic" looking. :music_whistling:

 

Pictures to follow soon.

 

Glad to hear you are enjoying my build!:)

 

M

220px-Chambers_1908_Bell_Crank.png.761d2d2c76e7a3c17942d44cb29391f4.png

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Love this thread, the build is great. The little triangle thing you highlighted in red is known as a bellcrank btw, pretty common to find in real aircraft linkage for the same reasons, to transmit mechanical forces around corners/obstacles/at angles. http://richshangar.com/wp-content/uploads/2012/09/Outer-Aileron-Bellcrank-and-Push-Rods.jpg

 

It is a great thread indeed. A very simple build requiring very little in the way of special tools with a fantastic result!

 

Wait, is there a mag brake on the Huey collective as well?! If so I'll have to add that too! I know from a real Huey pilot that the pedals have mag brake, but with very low spring tension to the point that some pilots didn't notice it.

 

Mole that video clip was perfect. I understood the bellcrank being there, but wanted to see what materials you used and how you assembled it because I figured you had done it in a simple but effective manner like the rest of your build. =D

 

Since I have a microhelis.de cyclic already I'm looking to add a Mag Brake to that. It occurs to me that since it already has hydraulic damping I really only need springs on my mag brake if I leave those intact. This might help me solve my problem with not having enough space to work with.


Edited by TripRodriguez

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It is a great thread indeed. A very simple build requiring very little in the way of special tools with a fantastic result!

 

Wait, is there a mag brake on the Huey collective as well?! If so I'll have to add that too! I know from a real Huey pilot that the pedals have mag brake, but with very low spring tension to the point that some pilots didn't notice it.

 

Mole that video clip was perfect. I understood the bellcrank being there, but wanted to see what materials you used and how you assembled it because I figured you had done it in a simple but effective manner like the rest of your build. =D

 

Since I have a microhelis.de cyclic already I'm looking to add a Mag Brake to that. It occurs to me that since it already has hydraulic damping I really only need springs on my mag brake if I leave those intact. This might help me solve my problem with not having enough space to work with.

 

Hi Trip,

 

I found this....

 

http://incolor.inetnebr.com/iceman/helicopt.htm

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Mole, Excellent thank you.

 

I think I have figured out a design that will work for me in my head but I have to draw it to be sure. Can you point me to what relay you used? Might save me some time shopping.

 

Trip


Edited by TripRodriguez

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Trimmer relay and circuit diagram

 

Mole, Excellent thank you.

 

I think I have figured out a design that will work for me in my head but I have to draw it to be sure. Can you point me to what relay you used? Might save me some time shopping.

 

Trip

 

Hi Trip,

 

Here i a pic of the relay switch I used. I am sure they are quite generic, and readily available locally. This was not actually the one I wanted, but the one they had in store. It was near me and I did not want to wait for a few days delivery.... It works.

 

attachment.php?attachmentid=165399&stc=1&d=1499323812

 

And here is my circuit diagram, complete with spilled coffee stains. The second contact 87a in the relay is redundant.

 

attachment.php?attachmentid=165398&stc=1&d=1499323812

 

My collective brake will be on a second 12v circuit. I have to test the collective brake button today to see if it is PTM or PTB. Hope its PTB....

 

I have been puzzling over my collective build. Trying to keep it all neat and tight. About to experiment with a new shape of bell-crank triangle. I realised that a right angle triangle with equal legs and the pivot at the right angle will move the link connectors equally. However if one leg is 2 x the other, then one link will move half as far when pushed. So trying that out this morning. I dont need the magnet plate to move as far as the connector rod from the collective lever. A pic will explain better when I have done it.....

 

Later!

 

M

trimmer-circuit-diag.thumb.JPG.232ce6db3dbd9276a3267553a7222ddd.JPG

1961086067_12vrelay.png.22ea8d9b7c1066d440a5ed95b4c79287.png

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SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Collective takes it's place in the cockpit.

 

I have spent the past 2 days working on sorting out wiring for the collective. I have painted it's cradle, and beefed up it's rigidity. The Collective Brake button is a Push-to-Make so I need to add in a relay to the circuit again, just like for the cyclic trimmer. It is on it's own separate 12V supply.

 

attachment.php?attachmentid=165459&stc=1&d=1499449603

 

A magnet has been glued in place beneath the main lever pivot to be read by a well placed Hall Sensor. Another mounted in the centre of an epoxy putty disk which will sit inside the lever arm itself in line with the rotation centre of the throttle. (Currently both Halls are giving me grief! Ironic, considering how I have raved about their ease of implementation.... gremlins)

 

attachment.php?attachmentid=165458&stc=1&d=1499449603 attachment.php?attachmentid=165460&stc=1&d=1499449603

 

The magnetic brake is a different concept to the cyclic. I don't want the springiness of the cyclic force gradients, just a rigid gripping brake. So I designed a different type of brake using most of the same parts. It is connected to an irregular bell-crank, see images.

 

attachment.php?attachmentid=165463&stc=1&d=1499449603attachment.php?attachmentid=165462&stc=1&d=1499449603attachment.php?attachmentid=165461&stc=1&d=1499449603

 

So, work-in-progress, but nearly there! Still considering the engine control levers and how to implement them.

 

Hope you like it!

 

M:music_whistling:

collective-side.thumb.jpg.7120fb2d4768fe2fcdc805aafdb5ff14.jpg

collective-front-on.thumb.jpg.c1cad351a871ad03980fafe0111552bb.jpg

1535864917_collectivetop.thumb.jpg.0dcda6f13e00cb8574d613633a2425b6.jpg

580711345_collectivemag-brake-2.thumb.jpg.df9af285f7f96a06c3a6aced93c7555a.jpg

324009601_collectivemag-brake-bell-crank.thumb.jpg.1ab789ace2eb23268cb450e3f9e84d49.jpg

1779098453_collectivemag-brake.thumb.jpg.4a851d3a806ced721052084d6c7b7464.jpg

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Looking great Mole!

 

I got my magnetic brake assembly built, it's not very elegant but I think it's going to work well and didn't require modification of my sweet microhelis.de cyclic base. I'll be posting pics, and once I have the magnet installed a video clip, in my sim build thread.

 

Thanks again Mole!

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Hey Mole, just FYI I updated my thread with some pics of my Mag-Brake solution and an attempt to explain how it works. Now I just have to hope it works when I add the Magnet!


Edited by TripRodriguez

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A day of huge frustrations for me yesterday. The wiring of all these buttons and components has proved challenging.

 

Hall sensors are just not happy. Tried the Bic pen case method, tried rotating side to side over a wide flat curved magnet, tried moving toward a south pole magnet, blah blah blah... I don't know if it is the proximity of the 3 x electro magnets for the brakes, or some other issue. I swapped them out and spent hours rigging a couple of spare pots I found lying around from another old joystick. 3 hours later, pots installed after much wrangling and designing linked connections. What happens? The pots start smoking.... And give lousy readouts.

 

So I RIPPED them out and threw them away. Gonna try testing a Hall sensor without full install, just wire one up and experiment with it outside the main rig. Thing is, they work beautifully in my old collective.... Maybe I got a dodgy batch. I broke 5 of the little f***ers yesterday, twisting them about to get in a good position on the magnet, to no avail.

 

Anybody had any luck with accelerometer/inclinometers attached to a Bodnar board? Bodnar did not have any ideas themselves. I might just get another Edtracker, simplest and most effective perhaps. I just think it is a bit big to place on the Collective throttle handle.... I've got one on the cyclic and it is great, so maybe that's the way to go. Save a lot of trouble!!!

 

CHAOS!

attachment.php?attachmentid=165669&stc=1&d=1499850856

grrr-chaos.thumb.jpg.b3926a0f72b7df86b23fabf295d8c729.jpg

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Hi

 

this is the way I use the A1302 Hall-sensor:

A1302-mag.PNG.2f2f9187ceef4c9acc7971a69c354bd6.PNG

it detect the rotation of the N-S poles.

So you can detect a rotation of nearly 170°

The A1302 can be connected like a potentiometer. (+ / input / - )

For less rotation like in the cyclic I use 3D-printed gears to spread the angle from 20°-30° to over 100°.

regards / gruesse yogi

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Hallo Yogi149,

 

That's neat! Well, I have opted for 2 x potentiometers and some linkages rather than gearing. I can internalise the one for the throttle, and the one for the lever is driven by a linked lever system. The good news is the pots are giving me no trouble, and I did not want to order more Halls and still have the same problem. 2 Pots at £1.80 each seems worth the risk. Tested one already tonight on the lever. Works like a dream. I have lost hair over the past few days with Halls and old pots not working.

 

Vielen Dank' for your suggestion, I will look at that for another occasion.

 

Mole

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Hi

 

this is the way I use the A1302 Hall-sensor:

[ATTACH]165676[/ATTACH]

it detect the rotation of the N-S poles.

So you can detect a rotation of nearly 170°

The A1302 can be connected like a potentiometer. (+ / input / - )

For less rotation like in the cyclic I use 3D-printed gears to spread the angle from 20°-30° to over 100°.

 

I used to use the A1302, then I discovered the A1324... same form factor but 90deg range of motion and you can use even smaller magnets if you want. Better suited for most cockpit applications due to the reduced range of motion. Here's an album documenting some pots I made with Alegro sensors. When I made the album I was using the 1302's but have since switched but use the same magnets and relations. https://imgur.com/a/WkQtw

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Nice work!

 

I used to use the A1302, then I discovered the A1324... same form factor but 90deg range of motion and you can use even smaller magnets if you want. Better suited for most cockpit applications due to the reduced range of motion. Here's an album documenting some pots I made with Alegro sensors. When I made the album I was using the 1302's but have since switched but use the same magnets and relations. https://imgur.com/a/WkQtw

 

Hi Thadiun,

 

That's some cool building there! I may look at that too when it's time to upgrade. I still kind of need to sense the Halls differently. The pivot method does not relate well to my configurations.... On my old collective I was passing a Hall side on over a magnet. That worked well. Maybe I should order up some A1324's, play around a bit.

 

For now, I got my pots calibrated, my Edtracker joystick configured, and with only a few more buttons to connect, I could not resist a quick test flight.

 

Oh........My.......GOOOOD! It's like a new machine! The controls are sensitive, and with the mag brakes I can literally set my cyclic, set my collective, and let go! Talk about Cruise Control! I have to use trimmer and collective brake a lot more than ever before. The big old Hip is like a stable platform, I can literally put the gun-sight over a target and it does not move.

 

I think I need to position the Edtracker a bit nearer the cyclic pivot point, make a bracket for it so it is nicely level when the stick is fully trimmed at neutral, a few minor tweaks and adjustments of course. Tinker, tinker.

 

It does feel a bit like learning over, a new control system with new feelings. But it has been an almost spontaneous transition so far. Gonna have to put a new shelf up for all my unused sticks. Or sell them.

 

Still looking for a buyer for the Lynx cyclic which got replaced by my now beloved Mi-8/24 stick set.... Anybody?

 

Mole

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

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Hi

 

I am planning to create a collective of Mi-8 with a 3D printer.

I encountered this amazing thread when I was looking for materials.

I would like to make it as much as possible like a real one, so if you can do it you will be very helpful if you can take pictures of the size of the grip part and the back of the switch if possible.

 

Machine translation may be difficult to read, but thank you.

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Collective scale image

 

Hi Bunkaiototo,

 

There is a very useful website with loads of Mi-8 reference pics I found.

Szextant's blog Mi-8

 

In there I found many useful pics. But for your needs you cannot beat this one.

 

attachment.php?attachmentid=165860&stc=1&d=1500116042

 

I will happily supply more pics of my pieces, but I am away this weekend.

 

Talk soon!

 

Mole

hind-collective-scale-150.thumb.jpg.af425110bb8f10296484e3eb34cb385c.jpg

SCAN Intel Core i9 10850K "Comet Lake", 32GB DDR4, 10GB NVIDIA RTX 3080, HP Reverb G2

Custom Mi-24 pit with magnetic braked cyclic and collective. See it here: Molevitch Mi-24 Pit.

 

[sIGPIC][/sIGPIC] www.blacksharkden.com

bsd sig 2021.jpg

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