ForceFeedback in DCS - realistic or gimmick?

A question apart...

There's somethig about to use a third FFB axis for adapt a G25 wheel for make FFB rudders? I tried my G950 and my G25 for rudder axis, but rudder FFB don't work.

A question apart...

 

There's somethig about to use a third FFB axis for adapt a G25 wheel for make FFB rudders? I tried my G950 and my G25 for rudder axis, but rudder FFB don't work.

It may be because nobody has ever bothered to code feedback forces on the rudder axis due to a significant lack of hardware for the purpose, technically it should be very easy to implement and I for one think the G25 idea is genius.

Siegfried, I didn't spend much time tinkering with this, but I ran into it a while ago. It seems that in DCS all FFB devices share the same effects & forces, it's not split up for the appropriate channel.

I tried put roll axis in my G25 and alevator axis in G940 but G25's FFB don't work and unasigned X-axis in G940 working when roll trim is aplied.

Extrange.

Siegfried, I didn't spend much time tinkering with this, but I ran into it a while ago. It seems that in DCS all FFB devices share the same effects & forces, it's not split up for the appropriate channel.

Wait, wait. Do you mean:

1. DCS sends same signals to X1, Y1, Z1 axes of Device1 and to X2, Y2, Z2 axes of Device2 but effects e.g. on X1 and Y1 can differ

OR

2. DCS sends same signals to X1, Y1, Z1 so that e.g. your yaw axis gets the same effect as your pitch axis?

If 2 then this alone would answer this thread as: gimmick.

A question apart...

 

There's somethig about to use a third FFB axis for adapt a G25 wheel for make FFB rudders? I tried my G950 and my G25 for rudder axis, but rudder FFB don't work.

I have several FFB devices both “real” and “vibro”. Some time ago, I tried to convert one of steering wheels (Logitech MOMO) into rudder pedals. The conversion itself was not very difficult, but pedals do not work in DCS as intended. They have “centering spring” effect only, no trim.

I tried to understand what is wrong and come to think that DCS “do not know” FFB effects on pedals axis (in fact on any axes except pitch and roll).

I can have different FFB devices in DCS simultaneously. If I do not set FFB on them to zero they have force effects, even if they do not have assigned control axes.

Looks like DCS use “standard” effects without taking into account which device/axis assigned in control options.

Wait, wait. Do you mean:

1. DCS sends same signals to X1, Y1, Z1 axes of Device1 and to X2, Y2, Z2 axes of Device2 but effects e.g. on X1 and Y1 can differ

OR

2. DCS sends same signals to X1, Y1, Z1 so that e.g. your yaw axis gets the same effect as your pitch axis?

 

If 2 then this alone would answer this thread as: gimmick.

As far as I can understand, it sends signal to “pitch” and “roll” of every device. And probably “pitch” and “roll” are hardcoded as Y and X.

^ Yes, that's pretty much my understanding.

I had an FFB wheel hooked up with an FFB stick, and it seemed that the wheel's X axis (steering) was mirrored with the stick's X axis. I suppose this means that the sim sends out X, Y, (and perhaps Z) FFB commands to anything listening, without regards to the actual assignment. An X on rudder gets the same command as an X assigned to aileron.

Effects between X & Y are definitely separate though, I was flying the P-51 once and got both ailerons shot off by AAA, the X axis went completely slack but the Y axis still had force. :joystick:

I don't know if there is a FFB stream available for Z to make FFB rudders work, but in order to use it you'd need to either somehow change the way the device presents that axis to the OS or how DCS handles the FFB export to individual devices.

Is FFB a gimmick in DCS? Not as bad as some sims that try to give the pilot the "total feel" of the aircraft through the stick. Stuff that you should feel through your butt is instead run through the FFB stick because that is the only FFB device the sim developers have available to give you immersion. This kind of feel is a gimmick. IL-2 Sturmovik was kinda bad about this. Shoot your gun, and the entire stick shakes so much you can't stay on target. Aircraft shake from gun fire, yes, but the shake should be felt through the seat, not the stick. At least not so much that it actually affects your accuracy.

So, is FFB in DCS a gimmick? No, because DCS does not seem to have the problem of excessive vibration for vibration's sake. The real question to ask is, does DCS implement _all_ the proper forces through the stick that should be felt through a real aircraft stick (which is the question the original poster was asking). That question is in the same vein as asking, does DCS implement an accurate fight model. The answer is pretty good, but not perfect. DCS is good enough, I would say, without being gimmicky. Plus, much of the problem is the inconsistent nature of the FFB protocol and how it is implemented on different joysticks.

I want FFB to get effects like the stick going floppy on you as you stall, proper trim feel, and to get rid of the unrealistic spring in a joystick. Real airplanes don't have springs on their sticks. The spring effect comes from wind pushing on the surfaces at speed. Stall out (no speed) and the stick has no resistance. Similarly, trim tabs are just that - tabs on the control surfaces that help push the control down/up, left/right so you can relax your hand and have the stick stay where you left it. FFB in DCS does this just fine, and to be honest, that's all it really needs to do. This is already 1000% better than a spring loaded joystick.

Now some technical stuff....

Sry if I was a bit unclear, let me precise what I meant (and as with everything on forums, if I'm wrong, please correct):

 

Yes, todays sticks are USB. The FFB protocol (Aka, the way FFB commands are transmitted) is still the old midi protocol from what I was able to read about it. That's due to the history of the technology which was introduced on the old midi/gameport 15-pin ports which back then were used for sticks and midi devices. Like on this beast which I still have around here somewhere:

 

...

 

What they did was use the midi capabilities of the port, which the sticks didn't use anyways, to transmit the control commands for the FFB motors over it.

I believe the FFB commands via MIDI was a Microsoft thing. Maybe other FFB controllers used the MIDI pin as well, but for a USB FFB device, MIDI doesn't matter. USB has it's own PID (Physical Interface Device) layer which is used to implement FFB. It's part of the standard, just like a keyboard, mouse, or common joystick are part of the USB HID (Human Interface Device) standard. As far as I understand, you don't even need a custom driver to implement a USB FFB device, just like you don't need to write your own driver just to implement a mouse or keyboard. These "basic" devices are part of the USB protocol, and all computers that support USB support these protocols.

Look for the USB PID document on USB.org for more information. This doc completely explains the FFB commands that can be sent via USB to a FFB device. As best I understand, FFB is defined in DirectX (the higher layer), and the generic USB PID driver (the lower layer) sends those DirectX FFB commands to the FFB device. The variable part is what commands the sim chooses to use, and how well the USB FFB device implements those commands. There are several hundred possible commands, but the most basic are joystick position and spring tension settings, plus basic sine, square, triangle, etc. wave pulse trains.

Regarding the Microsoft Sidewinder FFB Pro and MIDI FFB...

In the game port days, Microsoft wrote a driver to convert the DirectX FFB commands to MIDI commands for the original FFB pro.

Check out the adapt-ffb-joy project (https://code.google.com/p/adapt-ffb-joy/). It is a USB to game port adapter for the Microsoft Sidewinder FFB Pro. They have lots of information about the FFB protocol, and historically how it applies to the FFB Pro. I built one and fly DCS P-51D and the Huey with it. It's great. They did this by using the USB PID specification and an Atmel microcontroller to convert the USB PID to MIDI FFB commands for the FFB Pro. The USB PID is commonly known (documented), but they had to reverse engineer the MIDI FFB commands.

Regards,

Mike

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Great idea for a test actually!

Please, anyone with a FFB joystick, do something like this

If the stick gets lose at the top, the FFB in DCS is remotely realistic. If not - it's a gimmick!

It also applies to stick forces on ground:

a) engine running at high thrust setting - close to no forces on roll axis, some force on pitch axis

b) engine not running - no forces on either of axes!

Also, I don't think you can blame FFB itself. If it performs badly (e.g. stick is loaded by spring forces on ground, engine not running) then you can only blame sim developers.

Not realy what you asked for... but do you know PeterP´s awesome modifikation of 2x MSFFB2

that i would like to build too?

Stall Warning A-10C

Stall FFB in P-51:

Great idea for a test actually!

Please, anyone with a FFB joystick, do something like this

....

If the stick gets lose at the top, the FFB in DCS is remotely realistic. If not - it's a gimmick!

 

It also applies to stick forces on ground:

a) engine running at high thrust setting - close to no forces on roll axis, some force on pitch axis

b) engine not running - no forces on either of axes!

On the warbirds, the stick loses control pressures at low/zero airspeed. In the other aircraft, it remains constant (as far as I've noticed) throughout all airspeeds. I asked about it a while ago and the answer I was given is that those aircraft have hydraulic controls and the control forces don't vary with speed.

On the ground, same thing. Zero force at zero speed, I've never noticed if there's any elevator pressure from the propwash, I'll have to go check it out.

I also have G940 and in P51 when I have 0 kph the stick is flabby with zero pressure. As the speed increases the stick gets stiffer but not really really smooth. Is not choppy but gets stiff pretty quick to maximum pressure.

Also in helicopters the trimming effect is not a gimmick the stick stays "roughly" (depending on DCS FFB bug version :D ) in the place you were holding it when "trim" was depressed. In jets trimming moves the stick to the direction of trim, again does not look/feel like a gimmick.

Overall the FFB is good in DCS. Maybe the shake when firing guns was not too realistic but more of a gimmick.

. In the other aircraft, it remains constant (as far as I've noticed) throughout all airspeeds. I asked about it a while ago and the answer I was given is that those aircraft have hydraulic controls and the control forces don't vary with speed.

.

This is incorrect at least for MiG-29 and Su-27 which feature artificial feel (force feedback) systems. So the stick should get lose for these.

Other contemporary aircraft with hydraulic boosted controls also have artificial feedback systems. I just don't know the details. In any case AFAIK an aircraft without such system is uncertifiable as it would be a flying coffin. At least a spring is required. Even with only a spring the forces on the stick won't be 'constant'. Unless the development of the control system has been outsourced to one of the manufacturers of the shitty commercial sim controls we have to deal with that is.