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PROJECT: COUGAR COLLECTIVE v2

December, 2015

I think my number one choice for simming is helicopters.  While there are plenty of options out there for traditional throttles, there just aren't many choices for helicopter collectives.  For those that don't know, in a helicopter your collective controls the pitch of the rotor blades which primarily control altitude or up/down.  Your cyclic (stick) controls the angle of the entire rotorhead, thereby controlling speed and left/right roll.
So having a collective has always been one of my desires for the simpit.  I built my first version back in 2011 using a Thrustmaster Cougar joystick I had retired when I bought my TM Warthog.  I wanted a collective that not only controlled the rotor blades, but also had some controls on it for other functions, similar to the HOTAS idea in modern fighters and combat helicopters.  By using the Cougar as a starting point, I didn't have to do any fabrication of the grip, buttons, or controlling software.  But there were some challenges with the way I did it the first time, so that experience led me to creating version 2 of my Cougar Collective mod.

Keep the End in Mind

I had some parameters I had to workwith, mostly involving the location and size of the area that would house the guts of the collective.  I also needed it to be a specific distance from 'floor level' in the pit so that it would be a comfortable reach from 0 to max pull.  That drove most of the design choices for the overall concept.

I also wanted to have it very neutral in pull, so that no matter what position it was in, it would naturally stay there, but yet it wouldn't be a huge strain pushing and pulling it up and down during long flying sessions.  That led me to using a counterbalance along with some dampers.  All in all, I'm VERY happy with the results.

Where to Start

This was my starting point, the version 1 Cougar Collective.  You can see I had a counterbalance on this one too, but it was a spit and bailing wire approach.  It was built using spare parts laying around the garage.  Flew like it was built that way too!  We'll call it... clunky.  

The Base

In the version 1, I built it around the concept of leaving the Cougar base in tact and going from there.  This really was the crux of the problem for me.  Didn't know it at the time, but after a couple years of success and failure in using it, I finally decided to do a proper job of it.  

First Looks

Once I ripped the guts out of the Cougar base and did some research, I came up with the basic design.  I freely admit that I built my work upon the success of a few of my fellow sim rotor heads over on Sim HQ, especially GrizzlyT

The collective extension shaft and cross connector at the pivot point are all PVC conduit parts.  Much cheaper and lighter than aluminum, and easier to aquire and work with as well.  They are also very rigid and durable.  The pivot itself is a 4-way PVC fitting with an 1/2" aluminum pipe for the axle, set into a couple of collar bearings that fit perfectly into some pipe flanges I used to hold them onto the top of the wood side supports.


Cable Runs

This was a test fit of the stick and PS2 extension cable.  I was planning on cutting and shortening the PS2 cable, but I found having the 1.5 meter cable didn't effect performance, and I had enough room in the Junction box fitting I used for the offset to just roll up the extra cable.


Dampers

I reused the two dampers from the version 1 mod.  These are a matched set of dampers, one is pull resistive, the other push resistive.  It gives a nice balance and resistance to the collective, taking just a bit more effort to pull up than to push down.  

You can also see the mounting location for the Cougar control board.


Pot Protection

With how the whole unit mounts in the console in the simpit, I was afraid I would hit the potentiomenter while installing the collective, so I reused a piese of scrap angle strut below the pot to keep it from hitting the sides.

You can also see another shot of the two push/pull dampers.


The Collective Brain

Another shot of the control board out of the Thurstmaster Cougar.  I only needed the x axis for the collective, so that is all I installed.  I tried to reuse an original potentiometer from the Cougar, but they were both very worn and were giving jumpy input readings.  




Rotate This

I looked for awhile for OEM replacements for the TM potentiometers in the Cougar, but I couldn't find them anywhere, and had no luck with getting them direct from Thrustmaster.  Strike One!

So my next thought was to try going with a HALL sensor.  I didn't want to build my own, but I found a preassembled one from Honeywell that was less than $10.. but after about a month of fiddling with it and a few email conversations with some techs from Honeywell, I decided I just couldn't make it work.  Strike Two!

After sulking for a week, I went ahead and found a high quality pot that matched the tech specs for the orginal TM pot, and it works perfectly.  I epoxied a simple knob that came with the pot into the end of the center alumimum shaft that is pressed into the bearings on each side of the pivot.  I was surprised that it worked perfectly on the first try.  Whoo-hoo!


Counterweight

The tail end of the collective is made out of a piece of threaded pipe, and matching pipe flange, and a 10 pound weight I had laying around.  What with the weight of the Cougar stick, and how far forward of the pivot point it is, I needed around 8.5 pounds of weight to balance it out.

I also wanted to be able to adjust the resistance on the fly, so I used an extra pipe bracket that is secured on the bottom end, wraps around the PVC axle housing, and then has a bolt/spring assembly on top.  By tighting the bolt, it creates resistive pressure on the axle.  I have found that I like a medium resistance level when flying light helos, and a little bit more when flying bigger ones. 

I still need to find a permanent handle, but until then, the nut driver works!




Top Shot

Another look at the collective just before installation.  




Final Look

Here it is installed and functional.  I am very happy with how it turned out, and it works GREAT!

I wish I could have mounted it just a touch closer to the seat, say 1 inch.  But with the ejection handle there (remember, this is a multi-function simpit), I couldn't get that close without risk of hitting the handle during flight.

It's still comfortable, but after about an hour or two of active helo flying (nap of the earth type stuff), I can tell my arm is getting more tired than it would be if it was just straight at my side.

Amazing difference what an inch makes...