OC Attitude Indicator Success!

[stevem]

For my Lockheed T-33 project, I have successfully reworked one of its attitude indicator to work with the OC Servo Motors Card. I have to say, the OC Servo Motors Card works beautifully! Not bad for one's first instrument. Now to the others...


https://www.youtube.com/watch?v=z612d-eoSiY

[gspannelljr]

would you be willing to share your command structure with me? I am having a hard time writing the correct command for my gauges.

[stevem]

Be glad to! It's modified from Manuel Velez' code:

// *****************************************************************************
// * Config_SIOC ver 4.5 - By Manuel Velez - www.opencockpits.com (http://www.opencockpits.com)
// *****************************************************************************
// * FileName : test_servo_pitch.txt
// * Date : 9/13/2015



Var 0005, Value 0
{
&ServoBank = 493
}
Var 0000, Value 0
{
&ServoPitch = 611
}
Var 0006, name ServoBank, Link USB_SERVOS, Output 1, PosL 1, PosC 511, PosR 1023, Type 1 // Bank
Var 0001, name ServoPitch, Link USB_SERVOS, Output 2, PosL 1, PosC 511, PosR 1023, Type 1 // Pitch
Var 0020, Link FSUIPC_IN, Offset $057C, Length 4 // FSUIPC Bank, *360/(66536*66536)
{
L0 = V0020 * 8.38E-008 // Convert to degrees (neg is right)
IF L0 > 60
{
L0 = 60
}
IF L0 < -60
{
L0 = -60
}
L1 = L0 * 5 // Calc degrees for servo
&ServoBank = 493 - L1
}
Var 0010, Link FSUIPC_IN, Offset $0578, Length 4 // FSUIPC Pitch, *360/(65536*65536)
{
L0 = V0010 * 8.38E-008 // Convert to degrees (neg is up
IF L0 > 25 // Limit 25 deg max
{
L0 = 25
}
IF L0 < -25 // Limit -25 deg max
{
L0 = -25
}
L1 = L0 * 5 // Calc degrees for servo
&ServoPitch = 611 - L1
}

[hyamesto]

Great job.
Regards.
Horacio.

[stevem]

Thanks! Believe it or not, I think I'm more concerned with getting the T-33 fuselage sectioned-off (to put in my basement) than I am rebuilding the instruments. That's really the big scary part of all this.

[SimSupervisor]

Nice work there.
I have an attitude indicator that I am looking at interfacing soon. although I will plug it into an arduino, the servos will do pretty much the same thing.

I hope to post results soon.

Is there anything I should concern myself with when opening the physical attitude indicator the first time?

[stevem]

Hi SimSupervisor,

Thanks. Nothing to concern yourself over… nothing is spring-loaded or hazardous. There are many small parts, some of which can be a little sharp, but nothing dangerous.

For mine, I gutted the entire contents of the attitude indicator (i.e., got rid of the gyros, motors, mounts, etc.). But, I kept the instrument-face parts. I built wooden mounting parts to house the two servo motors, controlled by the OC servo motors card.

I drew exact-scale pieces of the exact attitude indicator using Corel Draw!, and I designed the wooden mounting parts based on what I needed. This method enabled me to build the wooden mounting parts with a fair degree of precision. The brown pieces in the drawing are the wooden parts.

http://www.mycockpit.org/forums/attachment.php?attachmentid=10741&stc=1

[SimSupervisor]

I am hoping to be able to reuse some of the original guts instead of making my own cages, but if I have to, it will likely be very similar to yours: wood seems like a suitable solution :D

Why is block #2 longer, and not squared? to help with positionning?

[stevem]

Block 2 is a bearing for the blue rod. So, the blue rod rotates in the roll direction through Block 2, but the blue rod is fastened (glued) in-place to Blocks 1 and 3. The entire assembly is mounted into the original attitude indicator case at Blocks 2 and 5 (I drilled holes in the attitude indicator case and then screwed Blocks 2 and 5 into the case). Looking at the SIDE view, the bottoms of Blocks 2 and 5 are aligned with each other.

The green pieces are the plastic servo motor gear things that came with the servo motors.

[hyamesto]

Block 2 is a bearing for the blue rod. So, the blue rod rotates in the roll direction through Block 2, but the blue rod is fastened (glued) in-place to Blocks 1 and 3. The entire assembly is mounted into the original attitude indicator case at Blocks 2 and 5 (I drilled holes in the attitude indicator case and then screwed Blocks 2 and 5 into the case). Looking at the SIDE view, the bottoms of Blocks 2 and 5 are aligned with each other.

The green pieces are the plastic servo motor gear things that came with the servo motors.

The Block 2 is really a good idea to properly align of mobile pieces.
Every day i learn something new.
Congratulations, and good luck with the T-33 fuselage. (Luckily you're not building a B-36 Peacemaker....:D)

Regards.
Horacio.

[stevem]

Horacio, you're right… Block 2 is there to keep it all aligned, and surprisingly, it does it really well!

A B-36 sim? I guess one would have to steal it from a museum first… then, there'd be about 6,000 instruments that need rebuilding!

[SimSupervisor]

then, there'd be about 6,000 instruments that need rebuilding!
LOL. Yeah. These are the reason they invented glass cockpits.


That's also why I opted to build a Cessna. ;)

[iwik]

Hi Guys,
Great work Stevem.
Have a look at this tutorial, it takes a real instrument and removes so much and then shows you how to mount
two servos.
Les

http://www.opencockpits.com/index.php/en/download/item/how-to-build-an-attitude-indicator-with-servomotors

[hyamesto]

iwik:
Thanks for the link. (I had lost in one of my hards disks)

It is what Stevem did with his instrument.

Off-topic:

And about B-36 Peacemaker......look

http://www.nmusafvirtualtour.com/media/062/B-36J%20Aircraft%20Commander.html

Nice 360º panorama.

Check:

http://www.nmusafvirtualtour.com

in the Cold War gallery.. all the photos, and Stevem, your T-33 it is just up.....:D

Regards.
Horacio.

[SimSupervisor]

Thanks for the link Iwik.

I have no clue where the attitude indicator I have is from (no markings), but it is really different to the ones we often see and is depicted in this tutorial. Mine is bulkier, sturdier, and has no colors.
I'll post up pictures when I work on it, might be useful to others.

[gspannelljr]

a B36 would be cool! For my Attitude gauge I just did some mods and installed 2 servos internaly, very little custom parts were needed.
Glenn