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Robbie2g2
10-17-2011, 08:50 AM
Hello everyone,

I'll start off by introducing myself as I am new here, I am an Aeronautical Engineering student doing my final year at Brighton University, United Kingdom. I stumbled upon this site whilst doing my research for my project for my final year Bachelor of Engineering degree entitled "Designing a force feedback rudder system for a flight simulator." I must say I have hit a brick wall as I can't seem to find enough material. All I seem to find are patents which don't really explain how I go about designing the rudder system. Any pointers or help on how I could tackle this problem would be greatly appreciated no matter how small.

Many thanks in advance... ;)

Mike.Powell
10-17-2011, 11:28 AM
The term "force feedback" is used widely throughout the gaming industry, but in commercial aviation simulation the more common term is "control loading". I imagine that as you are in a degree program, information on control loading is your goal.

Active control loading systems in simulators generally consist of a position sensor which measures the position of the control, a means of applying force to the control, and a means of determining how much force to apply. The sensor could be a high end potentiometer, or an LVDT, or a hydraulic valve. Current control loaders generally use electric motors to apply the force. Older systems sometimes used hydraulics. The amount of force is calculated by an algorithm running on a small digital signal processor. Inputs to the algorithm include control position, airspeed, angle of air flow over the control, turbulence, control surface mass, inertia, cable stretch (if the simulated aircraft uses cables), friction, damage, and so on.

There are a few pages on control loading systems in the book Flight Simulation, edited by J. M. Rolfe and K. J. Staples. The book has a 1986 copywrite, so it's a little dated, but the physics hasn't changed even if the systems implementation has.

You might call or email companies that make control loading systems. Sales literature can sometimes be helpful by listing the factors used as inputs. Possibly you can speak with one of their application engineers.

Here are a few links to control loading manufacturers:

http://aerosyseng.com/products/controlloading.htm

http://www.servos.com/products/control-loaders-and-actuators.html

http://www.wittenstein.aero/170.htm

Robbie2g2
10-18-2011, 08:10 PM
Thanks for the information Mike, have been reading up a bit about the control loading systems and have a rough idea of the whole subject area (On the internet). I will have to see if I can get my hands on the book you suggested and am sure it would come in handy!!! Will get on with it and inform you on how I get on.

Noticed you do flight deck books as well, are they pc specific simulators or can be fitted in a real sim?? The university has a grounded Socata TB-9 which we use for simulation, but unfortunately no one had attempted to get the rudder system to work.....Hence I have been tasked to get it to work :( which seems a bit daunting at the moment.

Mike.Powell
10-18-2011, 09:52 PM
Noticed you do flight deck books as well, are they pc specific simulators or can be fitted in a real sim??

I'm not sure there's much distinction these days.

I will say that the books are aimed at hobbyists who are interesting in creating highly realistic recreational sims. A recreational sim is designed to create an experience mimicking flying a real aircraft. A commerical sim is designed to train, develop, and/or test people and systems. While they have different goals, there is much overlap; the functionalities of many of the subsystems are the same.

fordgt40
10-19-2011, 04:44 AM
Some very useful links here

http://www.737flightsim.com/737center.html

http://www.737flightsim.com/737center.html

Both sites have a number of pages devoted to the subject - it is worth checking the whole site

David