Hi,Does anybody out there have any experience with Force Feedback mechanics and hardware/software.Currently, my column is balanced with gas springs and hydraulic dampers. It's nice, but not enough for someone willing to flight by hand all the time.I have the idea of using electric actuators, but does not have any experience how to drive it with which kind of electronics or could Servo Motor with strong torques be usefull too ??? But how much torque ??? I am actually a bit lost.Thanks in advanceBest regardsRogerAttached a pictures of my Short360 yoke-column and an update of my almost restored pedestal ( also Short360)

Hi Roger,Roland vanRoy probably has the most experience of anyone on this forum with electronics for driving large servo motors. He recently relocated from Taiwan (?) to the Netherlands, and has not been on the forum here for some time. Perhaps he will resurface soon. I think he would be a very good resource for you.As for torque... Do you know how much force you want to appear on the yoke? With that number you could work backward through the mechanics to derive the required torque.Do you need high frequency response from the control loading system? For example, do you want to be able to put a 20Hz vibration on the column? Or, do you simply want to be able to vary the loading slowly? High frequency response is expensive. Slow changes in control loading are substantially less so.There are commercial force feedback systems. Perhaps the sales/technical literature would suggest some ideas? The term "control loading" is used in the commercial simulation industry. A web search should turn up some useful information.There is a class of AC induction motor called a "torque motor" that is designed to apply a constant torque at stall or low RPM. I had some ideas of using them at one time for control loading, but have not taken the time to pursue it. Perhaps you would find them of use?Wowwaah, after reviewing this, I realize I am seriously low on caffeine...Mikewww.mikesflightdeck.com

Dear Mike,What would be that forum without your input. We should call that forum, "Mike's simpit builderforum".I will suggest it to the Avsim people. Anyway once more you habe been so nice and helped a lot so I can make some steps further.A low force feedback response would be enough. I am not looking for some "Theme park" violent reactions. -By the way, did I tell you that I directed 10 years ago a so called Showscan ride film , "The Devil's mine ride" which ran for years at the L.A. based Universal Film Tour, in a theater just close to the entrance. Huge success, bad contract, no much money came out for the makers. Showscan Film Corp, a company based in Culver city, for which I use to be creative consultant in Europe was the pionner of 6 Axis motion simulation for the entertainment business- To come back to the thread, I believe that the pressure felt on the yoke when flying the real thing is the effect I am looking for.Shaking just before stall or while flying in strong turbulences is not yet the goal. Do you believe that the electronic harware used in Force Feedback low cost joystick could be helfull to drive heavy AC Torque Motors ??Kind regardsRoger

I agree, Mike rules :-)>Do you believe that the electronic harware used in Force>Feedback low cost joystick could be helfull to drive heavy AC>Torque Motors ??I was thinking of the same - the hardest part would probably be the drivers - just like motion systems. I would guess if there is a force feedback joystick with *good* force feedback (dont bother with MS Sidewinder2, it has a disturbing and noticeable lag in the forces)- then you could perhaps use the electronics as a starting point and feed the signal to some kind of an amplifier circuit and drive bigger motors with it. But first one needs to find a joystick that is satisfying enough.Of course the simplest thing is to tighten the pressure when flying with faster airspeed and loosening it up when flying slow, that would be a lot easier I guess. And might even be pretty nice as well.Tuomas

Hi Tuomas,There are several effects, The first and most important effect is the trim effect. This effect alone would already be fine to simulate, then comes inertia depending on a type of aircraft.Stall buffeting, cable stretch, and friction would be great but are not what I am looking for in a first time.Kind regardsRoger

Hi Mike,I found on the Net this site:http://www.herbach.com/Merchant2/merchant....s_Stack_Depth=0Do you believe that they would have an interesting item for my purpose ??I am not sure how many RPM I do need and if for instance 30 Lbs torque would be enough for a yoke column.Kind regardsRoger

The DirectX development kit comes with a Force Feedback editor for creating your own effects using DX functions. All you would need (easier said than done :-roll) is a device (USB or otherwise) that can read this DX data which is in standardized format. No custom drivers needed, only hardware that can read this data.Maybe someone can tell me if FS2K has built in force feedback features you can activate or does one have to use FSUIPC to read sim data to generate these forces? Basically what I'm asking is, does anyone have a force feedback Joystick and how does it work with FS?-Leo

Hi Leo,Could you bring up such kind of electronic hardware?? A PCB would be enough. USB of course because you are our USB expert, arent you??Would be great!!!!!!!!!!!!!Thanks LEO:-beerchug

One thing to keep in mind....is when calculating the force that you want to "feel" at the yoke, is not what you will need for your effecter. What you need to consider is the leverage factor...for example, if your column is 32" from the floor up to the yoke, and below the floor is say 8" to the connection to the motor, or other means, you have a 4:1 ratio of force. So, if you want to feel an 8lb pressure at the yoke, you need to exert about 32lbs with your motor.Just something to keep in mind.KenDakenSkys

This is a good forum because so many people with diverse skills and perspectives can add to partially developed ideas and make something useful of them.And speaking of partially developed... Here are some further thoughts on control loading.Imagine that you wish to feel a peak force of 5 pounds on a yoke mounted on a column 30 inches long. This corresponds a delivered torque of 5 x 16 x 30 = 2400 in.oz. of torque. Further image that you want this force to be delivered as you move the yoke through a 10 inch movement in 200 milliseconds. This corresponds to ( (10 / (2 x 30 x 3.141))/ .2 ) x 60 = 16 RPMThese are our ballpark numbers: 2400 in.oz. at 16 RPM.A small ac single phase induction motor, say 1/6 HP, delivers on the order of 100 in.oz. at about 1600 RPM.If we wanted to directly drive the column we would need a fairly large motor, perhaps a couple HP: expensive motor and drive electronics, not to mention heavy and bulky.Better to use a speed reduction arrangement of gears or pulleys on a smaller motor. As the speed is reduced, the torque is increased. Ignoring losses, our hypothetical 1/6HP would deliver 10000 in.oz at 16 RMP if used with a 100:1 reduction unit.There are some issues, of course. We cannot ignore losses. We will certainly lose a few percent and may well lose much more depending on the quality of the reduction unit. Nonetheless, this approach has some appeal.Some more issues:A speed reduction unit multiplies the inertia of the motor

I was only trying to point out that there may be a simple way to extract force feedback data and somehow get this out to a motor through some hardware.Sorry, but I really have more questions than answers at this point.-Leo

Hi Leo,I

I think the most difficult part is working out the actual hardware side of things, i.e. motor and the mechanics associated with it. Then it

Hi Mike,Great explaination. I had a bit the intuition of going ahead such problems but I knew that you are able of putting it in equation.I also have token contact with some companies specialized in that kind of torque motor for real simulator.Will see what they will tell me. What would you think about hydraulic dampers, electrically driven, like the one used in robotics or in a real sim as 6 axis base ??Kind regards Roger

Hello Roger,Control loading using hydraulic components has been used in some commercial FS systems for some time, apparently with good fidelity. So, it's certainly doable. However, I haven't given electro-hydraulics a lot of thought. I looked into it a year and a half ago when considering motion bases, but tabled it when I began working on instrument simulations. Mikewww.mikesflightdeck.com