Any ideas on how to hook an altimeter (any type) to a computer through the USB port so the computer can read the data???

You'd have to gear the FS output data to a step motor I should think, and that would not be easy to calibrate...

 

In simple terms, an altimeter's output reading is controlled by a thin metal box with a vacuum in it which is exposed to the outside air coming from the static port, that box compresses or expands based on the surrounding air pressure, which of course changes with altitude, the expansion or contraction is read by a transducer and converted into an electrical output which can drive the needle on the gauge. So you would have figure all that out and have the gauge read the data coming from FS instead, then convert that to a signal able to drive the altimeter's needle. The FS SDK has info on how to tap that data when designing gauges, and that part is relatively easy to understand, the tough part would be the engineering necessary to translate that data into something able to drive the needle on the altimeter in an accuately calibrated fashion, and you'd probably need to power it too.

 

Frankly, you would be far better off just buying one of those Saitek gizmos, although if you are not to be deterred and want to convert your real altimeter, then you might want to check out some of Leo Bodnar's circuit boards:

 

http://www.leobodnar.com/

 

Al

It might be easier to just buy one, as Al has said. Here is another option. http://www.simkits.com/product.php?prodid=1008

If you're asking about a real altitude signal...

I think you can actually plug a small cheap GPS receiver into your USB port.

"so the computer can read the data???"

If you're asking about a real altitude signal...

I think you can actually plug a small cheap GPS receiver into your USB port.

"so the computer can read the data???"

 

That may well be the easiest way to obtain some type of usb port compatible "altitude" data, but do keep in mind that gps altitude will have no bearing on your altitude in relation to sea level or the ground or even pressure altitude. It would only be your altitude in relation to a mathematical sphere representing a notional earth. So whether or not it reads 0 while you're standing on a beach with the Atlantic Ocean lapping around your legs is anybody's guess.

That may well be the easiest way to obtain some type of usb port compatible "altitude" data, but do keep in mind that gps altitude will have no bearing on your altitude in relation to sea level or the ground or even pressure altitude. It would only be your altitude in relation to a mathematical sphere representing a notional earth.

 

With the addition of WAAS, which is available in the USA, to correct altitude data if necessary.......................the GPS reading will be more accurate than the altimeters pressure altitude, until the altimeter is again set to the current setting that's being flown over. WAAS corrected GPS is really that good! With XM Satellite weather, I can pick up new altimeter settings, and the GPS driven "six pac" panel page on my Garmin GPS will exactly replicate the airplanes altimeter for at least a few minutes. After a short period of time, the aircraft's altimeter will start to vary, and can be several hundred feet in difference. The GPS readout is very close to the exact elevation, while the planes altimeter is changing with varying pressures. For ATC, and aircraft separation, it's pressure altitude that will be used, since all planes in the vicinity should be using the same settings. WAAS uses land based facilities with exact coordinates and altitude, to make corrections to the GPS timing signals. This information is then uplinked to two satellites, that send the corrections to a WAAS capable GPS.

WAAS will certainly work but I doubt it will qualify as a "cheap gps receiver."

If you are interested in learning how to develope electronics this would be a good project.

 

First you must write software that reads the data from the sim (using fsuipc) and then sends it out through a USB serial-port.

Then you must program a microcontroller to receive the data and then drive some sort of actuator.

 

What sort of actuator this is depends on how you want to use the altimeter.

If you are willing to take out the guts of the altimeter or build one from scratch then you can drive the needles directly.

In this case you would use a servo or stepping motor as actuator.

 

Calibration wouldn't be difficult, as long as you build a calibration module into your system.

 

If you want to use a real altimeter intact then you must change the pressure of it's static port.

In that case your actuator will be a vacuum pump, a set of valves and a pressure sensor.

 

You could get an arduino as a simple entry level microcontroller.

Also have a look here: http://www.mikesflightdeck.com/

 

Edit:

If you want to read the altimeter data from a real plane then you should get a pressure sensor that you connect to the PC.

Trying to hook it into a real altimeter would be too much work.

If you're asking about a real altitude signal...

I think you can actually plug a small cheap GPS receiver into your USB port.

"so the computer can read the data???"

 

Yep - Real World. Sorry guys I should have said that in my OP

 

The problem with GPS is it lags behind, not as accurate and can lose a signal. But the GPS would be an easy solution.

 

I was wondering of their was a hand held Altimeter on the market that was digital?

 

Thanks Guys

WAAS will certainly work but I doubt it will qualify as a "cheap gps receiver."

 

True.

 

I'd just go with something that works electronically with the sim, and forget any real altimeter setup.

 

Yep - Real World. Sorry guys I should have said that in my OP

 

The problem with GPS is it lags behind, not as accurate and can lose a signal. But the GPS would be an easy solution.

 

I was wondering of their was a hand held Altimeter on the market that was digital?

 

 

Some GPS's such as my aviation GPS have very quick updates. It isn't like the old days. As I said, my GPS derived six pac presentation, exactly follows the airplanes. I've also not lost a signal in 17 years. I've owned five aviation GPSs since 1993. I do have a altimeter digital watch & handheld digital altimeter. It's been years since I've used them.

Cool, Thanks guys.

 

GPS unit seems the best way to do this. I think ParaGliders use digital altimeters so I will look at what they use as well and see if it can connect to a USB

 

Cheers

If you can't find a digital altimeter you could always try looking for a digital barometer (or any other kind of digital pressure sensor) instead. Will take some extra calibration on your part though.

BTW, what exactly do you want to with this?

GPS and a pressure sensor will tell you different things.

GPS gives you your height above sealevel which is not variable.

A pressure sensor will tell you where you are on a pressure gradient, which may shift up or down.

Trying to maintain a GPS altitude while everyone else is maintaining a pressure altitude is dangerous.

:) The first few replies were about using hardware to display FSX altitudes. Mentioning "real altitude signal" was just to see if the question was about some method of reading altitude in “real life”. I didn't mean to imply this sort of USB-GPS could be used as a flight reference ;) I doubt that's the OP's intension. What it could do is record a trip…for about $30.

Yep.....This is not flight related but for a project. Just need a device that will measure the altitude at various points and connect that with a computer, either USB or a Phidget.

 

Digital altimeter will do this as long as we can get it to talk to the USB or Phidget. We will shop around for something cheap and MacGyver it into a Phidget.

 

Cheers