hc625ma's cozy hangar

Some really cool and important upgrades for the reinforced gimbal here!  Here’s the list:

• Ethernet socket is moved to allow for gimbal rings assemble extraction without the need for removing it
• Y-axis magnet holder review/ adjustment hatch allows for easy adjustment should the need occur. It also allows for adjusting wires after everything is assembled.
• FTCR (Force Trim Center Reset) button was added. It allows redefining the recorded center position (it is recorded on controller startup). The button has its own housing and is connected to the rear of the gimbal through a separate  Ethernet socket.
• the most important upgrade: spring holder support ring! If you have built this thing by yourself, print and install it! This thing improves force trim operation and increases precision! It turned out that spring holders can rotate under load, thus moving the physical center position from its recorded (on controller startup) spot. Basically, this makes force trim operation unreliable. The support ring fixes the issue completely.

All changes (hardware and software) are pushed to repositories. The button uses 2 last pins of an Ethernet socket (white-brown and brown). The socket connects to 5v and A2 pin of an ADS1115 board inside of the gimbal.

You can now redefine the stick physical center (the spot where the stick is returned by springs) at any moment. Make sure the controls (cyclic and pedals) are absolutely still when doing this. This is useful in case you have pushed the stick to its boundaries, or just detached/reattached the stick, or changed its physical configuration (adjusted its lengths) without disconnecting the controller from USB.

Here are some pics:

And a video, that shows it in action!

Since we will have a Bell 206 in FFS, tuned by an owner of the real one, its default MILVIZ 407, ported from FSX, also works (more or less, its flight model  needs improvement, its systems are yet to be added), and there are great Dreamfoil 206 and 407 for X-Plane as well, I decided to take on the challenge of making a mechanical 206-style idle stop latch mod for a single collective =)

I am not yet sure how it will look, and what changes to the lever will be needed (as I see it now, 3 parts would need to be replaced, thus it won’t look good with a Huey head anymore).

We can also expect a 206 semi-scale head and probably a 407 one. Can’t say anything about when yet, but here’s a small teaser:



If everything goes right, with a good model of 206 made by a real pilot and backed up by affordable open source hardware, we can set a new standard of quality helicopter simulation, as a Dodosim 206 did some 10 years ago.

A while ago, I have been invited to join the closed beta testing of Flyinside Flight Simulator (FFS). It’s an interesting new project, focused on flying in VR. It focuses on high performance and gesture controls while scenery still looks great. For now, they are at the beginning of their way, but the project looks VERY promising, especially for us, sim heli pilots. That’s because they already have some intersting effects in their physics engine, like VRS (vortex ring), translational lift, different yaw authority in left and right pedal turns.

Whats even more important, they have a great community. One guy, RotorRick, is a helicopter pilot, who flies both 206 and a Rotorway, and happens to be a programmer as well. He was very kind to provide the 206 collective head and cyclic stick measurements.

Also, he wants to bring a proper flight model to us simmers. With such guys working on the sim, I am quite sure it will become the helicopter flight sim of the future.

I have updated the reinforced gimbal assembly manual page to reflect the latest changes in it. I decided to make adjustable spring holders a default option (these are really good) and put older ones to Mods directory for the gimbal. Don’t use them unless you have some problems with drilling (like not having a drill, but I would still recommend buying / borrowing one). The provided drill guide tool, used carefully, allowed me to drill as much as 8 holes, still remaining usable after that. I noticed that rinsing the tool with water helps a lot!

I have made a 2-hour flight in a 407 on VATSIM yesterday and absolutely loved how the gimbal worked. It was flawless!

Today’s a happy and highly anticipated day for a lot of us fellow sim pilots!

Merry Christmas to you guys and happy holidays to everyone!

I have tested redesigned parts of the gimbal and stick frame, and a few annoying issues I’ve been talking about in the previous post are now solved. Here’s the list of changes:

1. Tolerances of stick connector parts 3 and 4 were adjusted. If your gimbal is mounted under the chair, please print and replace them. This is important as old parts allowed for the stick to wobble.
2. Removed an unneeded connector nut from the stick connector bolt. This “decorative” nut was interfering with tightening things.
3. Thread locker is now recommended for use when assembling the gimbal. Manual has been updated accordingly.
4. Adjustable stick tensioners are now the default option. Old simpler tensioner model is moved to the mods section. I see no point in using them, new ones are way better.
5. Ergonomic IKEA GUNDE compatible stick frame was redesigned to be stronger, tolerances have been corrected to prevent possible wobble between parts. A second M8x200mm bolt was added to prevent turning of parts under load.
6. Software: fixed an error with stick center position being set incorrectly in extreme precision mode. Please update master controller firmware if you use springs with this gimbal.
7. Fixed some errors in file names.
8. Stick assembly process description with photos was added to the gimbal assembly manual.

All changes have been pushed to GitHub repos, please update. I will be updating the manual with photos, reflecting changes to the assembly process, shortly.

I have been testing the new gimbal for a while now, and while it worked very well, 2 things were not perfect:

1)bolts were getting loose over time, resulting in parts turning along them relatively to each other, requiring constant adjustments.
2) there was no mechanical spring tension adjustment, so no mechanical way to center the gimbal with a long and heavy stick

I have fixed the first issue by adjusting some tolerances (that were too big in some parts), adding thread locker in certain places (the manual is updated accordingly) and redesigning the stick frame.

I have tried a few different designs of adjustable spring holders, and finally came up with this one, which I called the “Star Destroyer” because of its look =)

I liked how smooth it is in flight, I’ve been able to center the stick perfectly, adjusting spring holders, parts won’t turn sideways so far.

I decided to make a test flight at fully linear controls setting in XPlane, with 100% firmware sensitivity mode, in the wind to test the precision of the gimbal, and liked the result!

Typically I would use 80% firmware sensitivity (extreme precision mode) along with 10% curve in XPlane, so cruising would require less concentration, to be able to enjoy the surroundings in VR, so that’s why there’ve been kinda weird attitude change when i tried to show force trim in cruise flight. Muscle memory, you know =)

New spring holders require drilling holes in bolts, so I have designed a printable drill guide tool for that.

I will be updating repositories tomorrow after additional testing.