Mainly for Mav-JP - 12 degrees stick axes offset
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This a just a question on viability since I lack the tech knowledge to deem it’s difficulty (or even possibility) to implement.
There is something that has been puzzling us pitbuilders since some got hold of real F16 transducers (force sensor):
http://www.viperpits.org/smf/index.php?topic=828.msg10702#msg10702
The sensor inside the case is rotated 12 degrees outboard. This means the sensor it’s not aligned with the stick and the aircraft longitudinal axis.
Our question was, does this mean that when you pull straight back in the stick you don’t get a pure pitch up input, but a mix pitch up-right roll? It did not sound logic but apparently so it is. It’s logic if you think about it from the ergonomics point of view: with a sidestick you can exert more force pulling toward your body than parallel to it. This twist in the sensor is mention in Dash-1 and there are also accounts that novel Viper pilots tend to deep the right wing when they pitch up:
My first Viper instructor predicted that I would over-rotate on takeoff and drop the right wing; he was right. The over-rotation occurs because a pilot is used to “moving the stick and then something happens” at rotation speed. When I reached 145 knots and pulled back, of course the stick didn’t move but a scant ¼ inch, so I pulled more. The inexperienced have no way of knowing how hard to pull, so I pulled probably twice as hard as was necessary. After a half-second delay, the nose abruptly responded to my input and pitched up to about 10 degrees, while at the same time the right wing dipped to about 10-degrees wing down
This is difficult to physically implement since all commercial force sensor HOTAS and Cougar mods are conventional fwd-back pitch, left-right roll. You can rotate the whole HOTAS but then your stick is looking in the wrong direction. You need some kind of custom made adaptor to rotate your stick regarding the sensor.
I was dealing with all this questions for making my pit when it dawn on me the idea that maybe it was possible to rotate the axis INSIDE BMS. Maybe as a setup/F4Patch option. Everybody who has a side placed stick would enjoy a more realistic experience.
So that’s my question for you Mav-JP/developers, is doable in a time lapse/amount of work that would make it worth to add an option taht rotate the stick axes 12 degrees outboard?
Thanks
Tulkas
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I think you got that quote wrong. For beginners over-rotation and right bank at lift-off occurs because they are not used for side mounted-force sensing stick. In F-16 it’s like in another a/c - if you pull stick straight a/c will go straight up for climb. IIRC further in the text there is description of hard turns with similar problems for beginners.
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I think you got that quote wrong. For beginners over-rotation and right bank at lift-off occurs because they are not used for side mounted-force sensing stick. In F-16 it’s like in another a/c - if you pull stick straight a/c will go straight up for climb. IIRC further in the text there is description of hard turns with similar problems for beginners.
pretty sure I have read of this 12 degrees rotated thing somewhere before. cant remember if it was a BMS dash or RL dash…
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Not sure if it’s relevant, but I remember reading somewhere that an F16 SSC isn’t lined up perfectly with the cockpit, but indeed rotated outboard. Had something to do with it being easier to put force on the stick correctly, iirc, as it would be more aligned with your arm.
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@GR1F-16CJ-1 1-127:
FLIGHT CONTROL SYSTEM (FLCS) CONTROLS
Stick
Refer to figure 146. The stick is a forcesensing unit
which contains transducers in both pitch and roll
axes, moves approximately 1/4 inch in both axes, and
is rotated slightly cw .Maximum noseup and nosedown pitch commands are
generated by 25 and 16 pounds of input, respectively .
Roll commands are generated by a maximum of 17
pounds in cruise gains and by 12 pounds in takeoff
and landing gains. When using the switches/buttons
on the stick, inadvertent commands to the FLCS are
possible.
The wristrest and armrest assemblies which may be
used in conjunction with the stick are located on the
right side wall aft of the stick.no details there, just that it is rotated slightly outboard.
also doesnt say whether that is the stick or the axes or both that are rotated.
yknow, it would be nice to be able to adjust the maximum force required for different gains…
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Probably I don‘t understand question, but seems that in all modern fighters sticks are rotated/twisted/something else. Still, to go straight up you have to pull stick straight up and not somehow diagonally.
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Why rotate the stick Inside BMS and force all users to have it rotated ?
while every one user can decide to rotate it or not with his hotas?this rotating thing is pretty useful (if not mandatory) for cockpit users but ridiculous for ppl using hotas on genuine office tables imho
and pit builders still are a minority (i am one myself)imho it really is not a good idea to make that move Inside bms.
for the record - (i don’t care if it’s real or not if it was only in the first blocks of the F-16 or not) but from my own experience flying in a full pit with the stick on my right side at knee level
it is much more intuitive and much more comfortable to have that stick rotated 12° outboard (and titled forward a few degrees) that way the stick vectors are perfectly aligned with the pilot arm and the actions of the sticks are quite natural and perfectly aligned with the references axis.
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had this in my cockpit pics folder, but it does not have any useful markings on it…
@Red:
Why rotate the stick Inside BMS and force all users to have it rotated ?
while every one user can decide to rotate it or not with his hotas?the first question, there is no reason to force all users to have a setting. Surely you are familiar with concepts like radio buttons?
for the second, ease of use. a software setting is MUCH easier on the end user than a hardware workaround.
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Guys, I can tell you what I know for sure:
The force sensor is rotated 12 degrees outboard (cw): ->FACT (at least in some F16 variants, I cannot claim to have seen pictures of all F16s SSC in the world)
The stick is not rotated (is aligned to AC long. axes): ->FACTNow, what I cannot say for sure -because I have not flown an F16- is wether the effect of the above mentioned facts is a rotated axes control, but the information I have points in that direction. I would love real F16’s pilots/engineers to chime in on this. Now, if you have not flown an F16 and you are just going to say what sounds logic to you or how you like to setup you Cougar, you are adding little value to the subject.
Probably I don‘t understand question, but seems that in all modern fighters sticks are rotated/twisted/something else. Still, to go straight up you have to pull stick straight up and not somehow diagonally.
Do you speak from your experience in the F16?
Regards
Tulkas
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@Red:
Why rotate the stick Inside BMS and force all users to have it rotated ?
while every one user can decide to rotate it or not with his hotas?Hi RD!
By no means I meant a change for everybody. If you re-read my post I spoke about a setup/F4Patch option. I agree with you that it is just for a minority.
Cheers
Tulkas
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Instead of asking for a software change, why not just build your pit to match reality?
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Instead of asking for a software change, why not just build your pit to match reality?
pull apart a cougar and have a think which is easier - software settings in F4patch, or building your own adapter to go between the sensor and the stick? you can rotate the stick and sensor 12 degrees easily.
rotating the sensor but not the stick would require some extra effort on your part to modify the cougar. I think the easy way to do this would be to take out the connection at the base of the stick grip, and create a replica one with the flanges on it set 12 degrees from their current position. only a guess though, as I have not even gotten close to that stage yet.
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Instead of asking for a software change, why not just build your pit to match reality?
Re-read my post, I said there, physically is damn difficult to do because commercial force sensor are not rotate. I am not asking for a change, I don’t dear beacause I don’t know how difficult it is, I just inquiring about it’s doability/difficulty. When I get that answer maybe I ask for it
Cheers
Tulkas
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Guys, I can tell you what I know for sure:
The force sensor is rotated 12 degrees outboard (cw): ->FACT (at least in some F16 variants, I cannot claim to have seen pictures of all F16s SSC in the world)
The stick is not rotated (is aligned to AC long. axes): ->FACTI just had physically modified my CougarFSSB to get that axis offset.
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I think the easy way to do this would be to take out the connection at the base of the stick grip, and create a replica one with the flanges on it set 12 degrees from their current position. only a guess though, as I have not even gotten close to that stage yet.
You still have the problem of the stick. You either get a custom made force sensor with the stick connection rotated regarding the sensor (where do you get that) or design and make (anyone?) a custom adaptor to connect the stick rotated to a normal force sensor. And that adaptor needs to be damn strong because you are going to exert all the control forces on it. Not easy to fabricate.
This is my setup:
Cheers
Tulkas
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I don’t think this request is valid, what you describe is a physical feature that should; not pass to a simulation through software. To accurately represent any side-effects from inexperienced visitors due to the stick actual angular displacement (front 13 degrees and right 12 degrees) in a real or home cockpit, you must install and use force sensors to the stick like FSSB-R2/3 or FCC-3. You can also spend your money on this Cougar grip adapter of Robert, to achieve the proper 13 degrees forward lean of a Cougar or Warthog sticks, either on there original base or the SCC, real or machined. The outcome before vs new:
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I’m familiar with Dunk’s adaptor, but it only corrects the leaning forward of the stick which is a pure physical feature. I got that right in my pit.
But for the rotation of the sensor (NOT THE STICK) there is nothing available as far as I know. I thought that to implement it in BMS would be no different than any other flight law: if pilot inputs back->aircraft pitch up and roll right. But again, I am not qualified to say so, that’s why I ask.
I just had physically modified my CougarFSSB to get that axis offset.
I have an FCC but I would be very interested in knowing your solution. Do you have it ilustrated in some webside?
Thanks!
Tulkas
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agreed, it must remain an hardware modification, not a software one.it’s easy enough to do
the fcc slides into the base, make a new set of holes into the base 12° outboard and you’re done, your fcc is rotated right 12°
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@Red:
agreed, it must remain an hardware modification, not a software one.it’s easy enough to do
the fcc slides into the base, make a new set of holes into the base 12° outboard and you’re done, your fcc is rotated right 12°
Then you are rotating the stick as well, and that’s not correct. It’s not easy at all to rotate the sensor but not the stick.
Cheers
Tulkas
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for the rotation of the sensor (NOT THE STICK)
Then you are rotating the stick as well, and that’s not correct
Are you sure that the real stick is not aligned with the real sensors below? So when these 2 are placed on the SCC they both should have the 12 degrees cw angle.
BTW the reason for this 12deg placement is due to the stick being in side, thus it needs to follow the physical pilot arm positioning and extension.