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PROJECT: Cougar Collective v1

December, 2011

I love helicopters!  I always have. I spent a bunch of time during my last few years in the Army in and around them, and it just reinforced that feeling.  So being able to fly helicopter sims using a collective and cyclic has always been a goal of the simpit.

Well, I finally took a stab at making one by modifying a Thrustmaster Cougar and turning it into a helicopter collective.  It's a little rough around the edges still, but the concept is solid, so I think I'm on the right track.
 

Start At the Beginning

I wanted my collective to do a little more than just control the pitch of the rotor blades.  I also wanted it to have some buttons and switches on it.  After coming up with some complicated custom designs, I was going through some spare parts and came across my retired Thrustmaster Cougar joystick and throttle.  I quickly realized that the Cougar stick could solve all of my problems.  So of course I did what any reasonable pit builder would do... started dissassembling the joystick!

Give Me Room to Work

I decided to keep the enclosure as is so I didn't have to worry about manufacturing a gimbal mount and getting the potentiometer mounted.  But I didn't want my collective to return to center when I let go, so I cut off the return spring stops.

Yes, before you send me an email telling me what a simpleton I am for not just taking the nuts off of the spring mounting brackets, removing the bracket, sliding the spring off, and then reassembling the unit instead of hacking it up with a Dremel... well... I thought about it. 

But with the Lock Tight they used on the nuts they really didn't want to let go. That had me thinking about what I would do if I sheared off the bolt, and if that happened once I pulled the plate off I wouldn't be able to get it on again correctly.  So I chickened out and grabbed the cut off disk and Dremel.  "Me man... bash stuff... okay.. no bash... cut... yes cut stuff... ugg". 

My wife says that whenever I get frustrated or overly concerned I am about to screw up... I always go for the biggest hammer I can find. 

I don't believe her...

Bits and Pieces

I knew that if I used a straight extension on the stick/collective, the grip would be too far away from the seat to comfortably fly for any period of time, so by using some PVC conduit parts, I made and offset extension.

To mount the extension to the joystick base, I just hollowed out the stock PVC coupler a little, then drilled and tapped set screws right into the Cougar joystick coupler.  Not very elegant, but it's stable as hell.

Ergonomics? Really?

In order to get the stick and extension turned into a collective, I needed it to be mounted horizontal instead of vertical.  So I started out by determining what angle the base unit had to be at and how high it had to be off of the base of the pit so that I could easily reach it, but also so that it would fit below the throttle tray.

As you can see in this pic, it actually goes lower than a straight 90 degree.. it's about 105 degrees off vertical.  The stick grip has a hand rest on it the ends up sticking almost straight up when oriented correctly for this application, so I had to account for that height when stowed... hence the negative offset.  Once I resinstalled the stick in the pit, I recalibrated the 'collective' to take out the bottom 25 degrees of the axis.  That way zero collective is not down at my ankles.

Pulled in All Directions

Next I needed to figure out have the collective stay boyant at all times. By that I mean that no matter where in the up/down travel you let it go, it will stay there. 

Before I forget, I need to give a big shout out to GrizzlyT from the SimHQ forums for giving me some great advice and input on the dampers and the collective overall.  It really helped!  I will also say that none of my frustrations or weird design choices came from him.  He could only do so much with my mental capacity!  THANKS GRIZZ!

So the dampers are not shocks, they a slam dampers.   Shocks always return back to the same position.  So putting those on would do the same as the centering spring I just cut out of the base.  When used in pairs (one extension and one compression) dampers will work to maintain the last position they were moved to.  I picked these up from McMaster-Carr.

Heavyweight

My issue was that the Cougar joystick grip is metal, and is heavy.  with all of the weight of that Cougar stick out on the end of the extension, I needed really strong dampers to keep it in position. 

I started with a set of 50 lb dampers, and that wasn't enough.  So then I went to 100lb dampers, and it still wasn't enough.  I finally ended up with 150lb dampers, and they just barely would keep the stick from slowly bottoming out once you took your hand off of the collective.  With those installed pulling up on the collective was a real strain.  So I started experimenting around with a counterbalance.

Zip Ties and Wire

I ended up needing 7.5 pounds of weight hanging off of the back via braided cable and a couple of pulleys, plus the 100 lb dampers to get it all to work.  This was the only combination I could find that would keep the collective neutral and still fit into the console in the pit.  I tought about trying to extend the shaft of the collective directly out of the bottom of the TM joystick base, but I don't have a lathe or mill, so I went with the shade tree mechanic method.  It works... but it isn't as smooth as I want.

But, it did fit into the pit console, and it does work, and I LOVE having the Cougar as the collective, but I think over time I will pull it out and find a cleaner, smoother solution for the counterbalance and damping.  More weight and less damper strenght I think.

Snug is an Understatement

When I say it was a close fit, I mean it.  You can sometimes hear the weight dragging against the back of the console, and there is less than a half an inch of clearance on each side.  I even had to remove one of the panel brackets to get it all to slide into place.

You can see that the collective extension comes ouf of the console via an angled slot.  This is cut to be a very tight fit on the extension so that it eliminates and side to side movement, leaving me with just up and down.  I used some Teflon tape on both sides of the slot to reduce resistance and wear on the extension.

A Star is Born

There is it, the Cougar Collective v1!  It's definately not perfect, but it does surprisingly well.  It's either a decent first edition, or an excellent proof of concept.

I'm going with the proof of concept idea... everyone wants to be a winner!

Where's my gold star???







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