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trolleydriver
12-06-2012, 11:44 AM
Jim,

First of all I want to thank you for your wonderful Link2fs program and all the valuable information on your website. It's opened up a whole new world for me in the hobby of flight simulation.

I got interested in the Arduino boards after seeing a post from John on the forum at another website (Note: this is the same John who recently asked here the questions about using two Arduino boards and two instances of Link2fs). From John's posts on the other forum I found your great website. I then realized that I had been there some time ago when I was searching for information about keyboard emulators.

I just purchased my first Arduino (a mega board) and have started to experiment with it. I have in mind using it for an annunciator panel, a flaps position indicator, an autobrake switch, etc.

Now for the question. On your website you show the use of meters to display such things as fuel quantities and flaps positions. What kind of meters are you using for these things? If this information is already on your website or this forum I offer my apologies for not doing an in depth search.

Again many thanks for what you are doing and sharing.

Clive

AK Mongo
12-06-2012, 02:18 PM
For gauges with less than 180 degrees of travel, servos are a great solution.

trolleydriver
12-06-2012, 03:10 PM
For gauges with less than 180 degrees of travel, servos are a great solution.

Way cool AK ... it makes sense. (can't believe at my old age that I am saying things like "way cool").

John UK
12-06-2012, 03:26 PM
Clive, I hope that you will post some pics of the gagues you make... Sounds interesting!

trolleydriver
12-06-2012, 04:43 PM
AK ... I'm very new to this. What kind of servo can I use? Is it possible to use a micro servo like the ones used in R/C helicopters/planes? Or is there some special type of servo for use with Arduino boards? Thanks in advance.

trolleydriver
12-06-2012, 10:57 PM
Found an interesting article on using analog meters with Arduino.

Arduino Analog Gauge | uC Hobby (http://www.uchobby.com/index.php/2008/02/12/arduino-analog-gauge/)

AK Mongo
12-07-2012, 12:14 AM
Almost any hobby servo can be used. They are not all standard in the direction of travel and the arrangement of wires within the harness. It may require a little research and tinkering, but it is simple stuff. The servos will need to be powered using external power, rather than off the board itself, but this is also trivial.

Reid

Jim NZ
12-08-2012, 03:47 AM
Thanks Clive ,,,
Good link for meter info ,, it covers it very well.

What I done was the same basically ,,, I used meters I had in the "junk box" and it worked out.
I tried some 4-20 milli-amp meters but couldn't get good FSD (full scale deflection) although the specs for the Arduino appear to be capable with 20 Ma ,, I put it down to a mixer of the PWM and the low voltage (5 volt) being the problem.

Most meters that have a FSD of 10 milli-amps (or less) or under 5 volts DC (or less) should work fine.

The 3 meters I used ,, 2 of them were 10 milli-amp FSD (it's an old industry standard) and the other one was a generic milli-amp gauge although I don't know its rating.

The 2 (10 milli-amp) meters are quite different to look at and they are called 'Edgewise" meters if that's what you were meaning. Google "edgewise meter" and look in "images".

Good luck ,,, Jim

trolleydriver
12-08-2012, 03:45 PM
Thanks Jim. I wasn't asking about the edgewise meters in particular but I have to admit they look great. There are some for sale on Ebay but they can be expensive. I've ordered a couple of regular 0-5 volt panel meters to experiment with. I'll also get a servo or two to experiment per Reid's advice. Keep up the good work on your webiste.

vikingsraven
12-11-2012, 08:14 PM
How about fitting a set of gears on the servos.
I'm going to try a 1:2 ratio that should give a full 360 degree,meter using a ser
I'm actually looking at old RAF gauges as well see if I can get them working.
Stepper motors also should work well.

Mike.Powell
12-11-2012, 09:12 PM
Gears on servos are a workable option. ServoCity sells gears which will mount onto a servo shaft. See:Servo Mount Gears (http://www.servocity.com/html/servo_mount_gears.html)

Something to be concerned about with very old aircraft instruments is that some used mildly radioactive luminous paint. I don't know if old RAF instruments fall in this category or not. The problem is that the paint binder degrades with time and allows the pigment to powder. Opening the instrument to modify it for sim use may result in inhaling some of the dust. The radioactivity is very low, but is still not something you want in your lungs.

vikingsraven
12-12-2012, 03:28 AM
Cheers for the reminder, yes they have radium in the dials.
That's not the only issue, been playing with a lot of war birds
Spitfires, hurricanes etc. And you have asbestos as well to contend with and mica dust, from some of the lens covers as well.

Re the gears, I may even try a pulley with an elastic band, that should also make it smoother as it will reduce the take up pull.

The main reason for using the original gauges is once I have my cockpit, I'm going to tty and build a full-size replica of the aircraft. Westland Lysander mkIIIa ed. One day!