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Comment by krallja | Hacker News Reader

Brakes, or a strong motor.

The way I would approach it (based on mechantronics I have done for robots) is to back up the control wheel with an encoded motor. (Position/rotation encoder on the tail shaft.) The encoder will give you wheel position, the motor allows you to apply arbitrary torque to the wheel to simulate the feedback forces felt by the pilot. Typically, that would be done by measuring motor current and writing a control loop that controlled for target wheel position (based on encoder) and target maximum motor current (as a proxy for torque). Then the simulator would give out the simulated results of wheel position and torque, which the control loop would attempt to follow with its control law.

Alternatively, you could put an actual torque sensor between the motor and the control wheel, which might buy you some accuracy at considerably more expense. For a flight simulator, expense is unlikely to be an issue -- I tend not to have that luxury, and typically don't need that much accuracy anyway.

These kind of control systems are all over modern aircraft, much less simulators. Any new grad control systems engineer should be able to knock something like this out.

> The way I would approach it (based on mechantronics I have done for robots) is to back up the control wheel with an encoded motor. (Position/rotation encoder on the tail shaft.) The encoder will give you wheel position, the motor allows you to apply arbitrary torque to the wheel to simulate the feedback forces felt by the pilot. Typically, that would be done by measuring motor current and writing a control loop that controlled for target wheel position (based on encoder) and target maximum motor current (as a proxy for torque). Then the simulator would give out the simulated results of wheel position and torque, which the control loop would attempt to follow with its control law.

Or you just buy a COTS servo that does all that for you. Just saying, hardly a need to reinvent these particular wheels...

Yeah, good point. I'm sure there are servos that have the required specs. I'm just not in the habit of looking at catalogs where the prices are that high :) Maybe I should switch to building flight simulators so that I can order the good stuff :)

racing sim guys already figured it out http://opensimwheel.wikidot.com/

crank handle with a translation?

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