Hi, lately i've been thinking about a way to add some turbulence and limited motion to my cockpit chair.What I was thinking was since the cockpit wont move, I could build some kind of platform in wich the chair will be and the platform would react to turbulence that's happening in the simulator.If the wings roll, the seat will also roll for 1 or 2 degres and when descending/climbing the seat will also descend/climb in small movements.What do you guys think of it ? Is it feasable ?? Practical or it will add some realism to the flight when passing bad weather or in wind shear conditions for instace???Best regards,Pedro

i think that the trouble it will take you to create this would be the same as making the entire cockpit move ..if you go trough with this .. make sure you don't get seasick (-:

>i think that the trouble it will take you to create this>would be the same as making the entire cockpit move ..>>if you go trough with this .. make sure you don't get seasick>(-:Well I dont think that way.The entire cockpit takes over 2 meter for 1,8 meter, so it's BIG. Another thing is the weight, the cockpit takes as much as 500 kg and you can weight 65Kg...The movement I'm after is not to replicate the 6 DOF that we see on the comercial simulators, I only want to add small movements.I'm not talking about a shaker for the low freq sound.Extracting the movements of the plane off the sim is no problem for me, what I want is some ideas on how it could be done and if it could be done reasonable well and if it will give us realistic sensations of flight.Best regards,Pedro

Hi Pedro,Adding motion is an ambitious venture and I commend you for wanting to try it. If you are building an all encompassing enclosure for your sim, the visuals alone will trick your mind and sense of equilibrium, so that you won't need "large" movements anyway.One concern might be...if the movements got too big, that you would have some conflicting frame of reference. If the airplane shell were stationary, and your chair moved, you might sense that your seat was moving while the airplane stood still. Add to this, the visuals out the window that were also moving, and you might be getting some confusing visual cues.If you can "breadboard" or mockup something before going full speed to build it, you might be able to get a better feel for the end results. You might start by sitting in a car with a power seat and play with the controls a bit while observing the relation to the car and the outside.As to controls themselves, there are several ways to consider...Hydraulics, just like the big sims, but expensive and complicated....pneumatics, using an air compressor and cylinders.... servos, which are gaining in popularity for ease of use, and some other inventive means like using vacuum instead of air power.Good luck and be sure to let everyone know how your experiments are working!Kenwww.DakenSkys.com

Hi Ken, I know what it takes to reproduce the movement like the big boys do it.I'm not after that because I've got no resources to do that and my cockpit frame is built now.What I'm after is only small movements of the chair, not the cues that fools us like they do it with the big simulators.Picture this: You're in your cockpit flying and the horizont isn't level, is moving up/down, rotating left/right. Your chair is doing the same in small movements.I was thinking about a servo to do this but I don't have any knowledge to choose the right one and work with it.Anyone as some ideas or experiences with this??Best regards,PedroPS: My little CRJ simulator ;)http://forums.avsim.net/user_files/49887.jpg

Pedro,I'm afraid I can't help much with the electronics interfacing for servos. Most however are rated in oz/in or ft/lbs etc and you would need to figure out about how much weight you need to move.If you can imagine your chair, on a central pivot point, similar to a playground see-saw, then you can calculate the force to move it up or down.One possible site that I know is: www.servosystems.com who sells many servos in all sizes. Most are quite expensive, but they do have closeouts from time to time. I had another good site for surplus servos but misplaced their name right now...I'll try to find it though. Perhaps some others here can offer their expertise on interfacing.Kenwww.DakenSkys.com

Pedro,Try these web sites...which have some info on servos and how to interface them:www.fursuit.org/faq/servo.htmwww.brookshiresoftware.com/how_sscs_work.htmwww.cpg1.freeserve.co.uk/servos/servos.htmwww.rentron.com/serialservo.htmHope this can help....Kenwww.DakenSkys.com

Hey, thanks!!!Let's see if I can learn something.Best regards,Pedro

Pedro,If you still need some help...let me know, and I'll ask my electronics tech and see what info I can get for you.Regards,Kenwww.DakenSkys.com

OK. Thanks,Regards,Pedro

I've been thinking about adding bank and possibly pitch to my little GA pit once it's further along. The concern though is getting the angle out - especially pitch. Bank is easy - the ball actually shows the 'perceived' bank anyway, so whatever it indicates needs to be changed to a physical lean of the pit. For a sim, that's the important one anyway - to balance a turn you press on the rudder pedal till you feel that you're upright, not watch the ball, so that's what I'd like to duplicate.For pitch, however, there are two values to be worked out - the true angle of pitch, and the fore/aft acceleraion/deceleration which affects the perceived pitch. Has anyone done anything toward working that out already?Richard

Richard,Disneyworld once had a space ride simulation that gave the feeling of acceleration and de-acceleration that was very believable. The way they did it was to allow the center of the seat we were sitting in to "cave-in" so to speak. It was controlled to sink to give the feeling that you were pressing deep into the seat, as if by a strong acceleration pressure. The seat would then move outward slowly as the initial acceleration normalized. Upon de-accel, the seat would push upward and give a feel like the brakes were on. A really great innovative sensation.Don't know if this is what you want to achieve....Pitch could still be an axis-servo control, but for the accel / de-accel, perhaps the above trick applied to the back of the seat.Kenwww.DakenSkys.com

In my believe the correct reproduction of movement-feeling is quite a tricky thing.If it would be a car, to simulate a left turn, you'd have to bank the entire cockpit to the right, not to the left. However, I think that in a plane that is not exactly the case. Because once the bank is established for a left turn you should not feel the force to the right, but rather down because you are pitching trough it.Acceleration is banking the cockpit backwards and slowing down is pitching it forward.While pitching up in the sim would be moving the entire cockpit up and pitching down would be moving the cockpit down. These movements need to be quite fast initially but have to stop soon and in such way that you don't feel it stop.I believe there's not much movement needed because I think you only feel the change in movement. So once you're going down in a plane you only feel it when it changes from level flight to going down while once it is established going down at a same pitch you only would feel it in your ears in real.I think that only the acceleration and braking would need big movements.What you can try is mod a chair. Put it on 1 leg (centered) instead of 4 and gind 2 rather strong people who can help you out. Then close your eyes and ask them to tilt the chair backwards slowly. Immagine accelerating and tell them to stop tilting backwards once you think you get the kind of acceleration feeling you get in a plane while it initially starts its takeoff run. Then open up your eyes and you'll see how much pitchangle you'll need on your sim to recreate the feeling. I got no idea how much it will be ... but if someone does try it out, pls let us know ! :)

They indeed say that if the movement is not well in sync with the visuals (with motion cues etc) you mostly just start feeling sick, so it actually can just make the feeling of realism worse than without.My friend who works with the "real" sims suggested that one makes just the acceleration/deceleration axis - basically put the whole sim in a platform that tilts fore-aft and map that to airspeed acceleration/braking with simple wash-out algorithm. The problem with just the chair moving is that you just make it hard to do anything in the cockpit in turbulence - you cannot take much support from the glareshield or such, and it just becomes hard to adjust the radios, buttons, throttles when you seat moves all the time.Just thinking the best thing is to make the sim non-moving if it is not being made to do "motion" from the start - like people said, removing cues of the "outside world" and making you see only the cockpit enclosure and the visual system really fools your brain into thinking of motion. Now if you then add a motion system that makes you think your seat is rocking, it probably feels like just that, and not that the plane is actually flying. Tuomas

>My friend who works with the "real" sims suggested that one>makes just the acceleration/deceleration axis - basically put>the whole sim in a platform that tilts fore-aft and map that>to airspeed acceleration/braking with simple wash-out>algorithm. The problem with just the chair moving is that you>just make it hard to do anything in the cockpit in turbulence>- you cannot take much support from the glareshield or such,>and it just becomes hard to adjust the radios, buttons,>throttles when you seat moves all the time.Hi Tuomas,It becomes hard to adjust anything also in the real world because the plane is constantly changing it's attitude.The chair will not move 15