Tag: simchair

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Helicopter pedals improvements

While building another set of helicopter pedals, I’ve accidentally cracked the wall of the frame in its weakest spot while press-fitting a 300mm piece of aluminum tubing.

As the frame is quite a long print, requiring some noticeable amount of plastic, I felt the need to do something with this problem (which I have already tried to address a while ago by inclining the tubing slot to reduce its shrinkage). As the fit is quite tight (which is intended) depending on a printer (and temp used to print parts, which should be higher than usual for pedals, I use 225 degrees centigrade for regular PLA, at first, try printing a frame leg and fitting it on a piece of aluminum tubing, it should not break), and also tubing used (there’s a tubing that is 9,8mmx 19,8mm and there’s a tubing that is 10,0×20,0) it may become overly tight. In this case, one needs to sand it a bit, but if the available clearance is misjudged, the frame can crack. Of course, that’s what happened to me (again!) =)

So, here’s the fix, that hopefully will straighten things out:

I have added 10mm extra width to the back of the frame and removed the forward slot for aluminum tubing because of aesthetical reasons (I’ve never used it anyway, and to make it reliable I would have had to add a similar “thing” to the front of the frame, which would have looked kinda out of its place). Note that I have also added a little chamfer, hoping to reduce shrinkage on edges thus reducing chances of an overly tight fit.

I have also added a mod with rubber band holders removed. I have been testing the spring-loaded version for a while now, and it works perfectly (better than rubber bands) yet this is a very refined thing I like to improve gradually. Besides, one can still use it with rubber bands just fine, but note that the latest force-trim mode for a spring-loaded cyclic will only work with pedals with springs. That’s because pedals have to return to the same exact spot every time when released, what actually cannot be achieved with rubber bands.

I hope to be able to print the new frame until tomorrow and tell you guys how things worked.

All changes are already in the repo.

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Adjustable ergonomic stick frame for a spring-loaded cyclic

After flying with a spring-loaded reinforced gimbal for a while, I noticed that slight backlash has developed in a stick connector part. While it was absolutely tolerable and that part can be replaced easily, I thought it was a good idea to design a new cyclic frame for those of us who value absolute precision over being able to remove the stick when not in use by simply pulling it off its socket.  The new stick frame is based on M8 bolts and mounted to the gimbal with nuts.  The cool thing about it  – you can easily adjust stick grip inclination (you can make a copy of AS350 stick for example) and fine-tune its dimensions to suit your anatomy. It can still be attached or detached quickly but requires 2 wrenches to tighten/loosen nuts properly. I think it will be a new recommended default for a spring-loaded cyclic.

As always, you can find parts for it on GitHub.

Here’s how it looks (note a slight inclination of the stick on the second photo):

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Test flight of the latest upgrades in Dreamfoil 407

I have installed the same clutch pedal springs from LADA 2101 to pedals and made a short test flight of the upgraded hardware in X-Plane.

Impressions:

WOW, THAT NEW FORCE TRIM MODE IS AWESOME, SO ARE THE SPRINGS (like that, boldly, in caps)! Springs have actually added precision and made flying really comfortable. This short flight in a 407 probably felt like the best flight in it ever.

It really changes everything. I’ve been able to remove hands from the controls and pour myself some coke while flying the helicopter with pedals only.

I will need a couple of weeks to test mechanical strength of things, and if nothing breaks, will definitely recommend everyone to try a setup with springs!

A short video of landing:

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Springs for a reinforced cyclic gimbal, new force trim mode!

I have finally been able to go to the local car parts shop and buy some springs for the gimbal. Here’s how it looks now:

Reinforced gimbal with springs!

 

I should start by saying it works just great. These springs are from some Lada’s clutch (i think they’re for the pedal), they are 55mm long when compressed and about 11mm wide. I am pretty sure any similar spring will work great, just pick one with light or moderate tension.

More (a lot more) below!

Continue reading “Springs for a reinforced cyclic gimbal, new force trim mode!”

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5x5x5 magnet holder for reinforced gimbal added

I have added modified holders for the reinforced gimbal that Guido has asked for. Sadly I can’t test them myself, so please tell me how these mounts worked for ya mate =)

There are 2 versions: the “a” version has the same distance from magnet to the sensor as 6x6x4 one, and in the “b” version, a magnet socket is lifted a little for an extra tolerance (the magnet is 1mm wider so potentially can touch the sensor with its angle when turned, tell me if you encounter this issue).

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Throttle quadrant released!

I have printed the quadrant, its parts seem to fit together quite well. I have also added firmware for it, for now, it supports 3 axes (3 more can be added easily).

Each slider has a reverse mode, programmed as a separate axis, so we can fly STOL aircraft =) This is the first version of the software, more features will follow. Let me know if you have ideas of useful functions for it!

Simchair MKIII universal throttle quadrant