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Delta Charlie
09-26-2006, 06:19 PM
I am building a flight simulator using a real Cessna 310 cockpit. It is fairly complete right now but I need to use the control system from the real aircraft, attaching potentiometers to detect all movements. The whole setup requires:

- A potentiometer for the rudder pedals.

- Some sort of sensor for the toe-brake system attached to the rudder pedals. Need two of these, for differential braking.

- Roll control - ailerons -, using a potentiometer.

- Pitch control - elevator -, also using a potentiometer.

Since the cockpit came complete with the "Y" stick used in the real aircraft, with its control cables and the whole setup, and I have attached springs to these cables below the floor and the pilot and copilot seats in order to make the thing feel more or less like the real thing, I could use linear or non-linear potentiometers; linear ones would be easier to install in this setup, but I donīt know if they would work better than the more traditional, rotary movement type, or perhaps, even accelerometers. Whatīs your experience with this kind of things?

For the toe-brakes I was thinking on using some sort of proximity sensors or accelerometer; would these be appropriate for such a use?

Thanks

alandyer
09-27-2006, 05:26 AM
Dear X,

I think you mean slider as opposed to linear.
Linear refers to electrical properties of pot.

Decision on which type of pot is going to be driven by available mounting space, budget, control travel, etc. Not many folks on forum have crawled around inside your cockpit. No silver bullet on this one :(

I speak from experience.
I have the cockpit of a Boeing 737, the 7th one built.
There is no general solution :(
For one control it is appropriate to use rotary pots, another slider pots, or perhaps rotary encoders.
Lots of research and design.
Watch out for those sharp aluminium edges.

Can anyone help X by providing a good source of long slider pots ?
That will be helpful.

Good luck on your project.

Regards,
Alan.

alandyer
09-28-2006, 10:45 AM
As a rule try and use long slider pots for sensing linear motion.
Rotary pots are difficult to calibrate mechanically beyond about 90 degreees of travel.
You have to imagine the path travelled by pot-to-control linkage as the pot is turned, particularly around highest and lowest points of travel. Think sine wave.

Brake pedals are design decision on whether you want to sense brake pedal travel or pressure in hydraulic brake lines. Hooking up slider pots are easiest.
Toe brakes on your airframe should have mechanical linkage to hydraulic master cylinder. Being a twin there is no firewall, but as I recall 310 has forward baggage compartment. Don't have copy of POH at hand.

Give lots of thought on where you mount pots.
You will have to access them for annual and 100-hour inspections :)

On previous post I mentioned that my Boeing 737 was 7th built.
7th 737 built by Boeing in 1967. Not 7th sim built by me.

JBaymore
09-29-2006, 02:24 AM
On previous post I mentioned that my Boeing 737 was 7th built.
7th 737 built by Boeing in 1967. Not 7th sim built by me.

Alan,

That comment had me wondering. :)

best,

..................john