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Old Feb 17, 2009, 05:44 PM
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la5xoa,

Hey! That is a very good tip. My gyro outputs at about 100dgr/s/V, and the maximum rate it can sense using the original OpAmp gain is 160-180dgr/s ish. I can easily turn my head faster which saturates the OpAmp.

I have considered changing the gain of the OpAmp, but I need the sensitivity because I'm planning to use it in my research tracking the orientation of machine tools. So I left it as it is, for now I have to remember to not turn too fast... But it's very good to know that the gyro can sense much higher turn rates! What sort of turn rates were you able to measure?

I have tried to find out more information of the gyro sensor itself on that board, all I know is that it's a Murata, the part number MA 740 does not seem to exist... Do you have any information about it?

I've bought another cheap gyro with heading hold (http://www.r2hobbies.com/proddetail.php?prod=rcps61801), this one claims to be MEMS, but the sensor looks exactly the same as the MA 740, apart from the fact that the part number is 823. I have not tested it for head tracking, but I thought it might be of interest to you because it uses a PIC16F716 instead of the Chinese micro controller on the ESky, I donno much about PICs, but you may be able to program it without taking it apart!

Cheers,
-Z-
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Old Mar 20, 2009, 06:58 PM
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Zitron,

Could you give details on how you separated out the sensor board on yor EK2-0704s, and how you interfaced to it (wires to what pads or pins)?

I've got a couple that I would like to interface to an MCU for an active stabilization project an wish to duplicate your efforts.

Thanks
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Old Mar 22, 2009, 07:38 PM
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Hi,

Sorry for the late reply. I should apologize to everyone for the poor quality of my documentation. Hope these pictures help. Please note that I might have the servo PWM output and input the wrong way around, I don't remember which is which.

Cheers,
-Z-
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Old Mar 23, 2009, 05:37 AM
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Wow, thanks Zitron, you are my hero. Just a couple of questions if I may:

- Is the board V_in really +3V? I would have thought it was +5V (it must get regulated down somewhere on the processor board?)
- Is Ref Voltage (V_ref) output generated on board, or is it an input generated external to the board?
- What does the 103 trimmer you added do (does it divide down V_in to set V_ref?)

Thanks again.
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Old Mar 24, 2009, 06:54 PM
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Quote:
Originally Posted by MGeo
Wow, thanks Zitron, you are my hero. Just a couple of questions if I may:

- Is the board V_in really +3V? I would have thought it was +5V (it must get regulated down somewhere on the processor board?)
- Is Ref Voltage (V_ref) output generated on board, or is it an input generated external to the board?
- What does the 103 trimmer you added do (does it divide down V_in to set V_ref?)

Thanks again.
You can power it with 5V from the servo lead, there is a regulator thingie on the sensor board. I think both the processor and the analogue parts run on 3V (or maybe 3.3V).

Yeah you are right. The Vref is apparently generated on the processor board, and is fed into the sensor board, I'm using the pot to send ~1.5V to Vref.

Cheers,
-Z-
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Old Mar 25, 2009, 06:59 AM
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Quote:
Originally Posted by zitron
You can power it with 5V from the servo lead, there is a regulator thingie on the sensor board. I think both the processor and the analogue parts run on 3V (or maybe 3.3V).

Yeah you are right. The Vref is apparently generated on the processor board, and is fed into the sensor board, I'm using the pot to send ~1.5V to Vref.

Cheers,
-Z-
Great. Thanks for the help.
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Old Apr 14, 2009, 11:49 AM
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Just a quick update, figured out how to get rid of geometric drift, it's just a simple 1/cos() thing. See pictures for details.

Someone asked me for the FSX camera program, click here to download it.

Cheers,
-Z-
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Old Jul 07, 2009, 07:10 PM
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this is an old post i see, but what if using an ir-camera like the one on the wiimote and a pair of googles with mounted ir-diodes... would that be possible?... i think the wiimote camera can have four points.. so that would be y/x axis....
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Old Jul 07, 2009, 07:14 PM
WHEN IN DOUBT FLOOR IT!!!
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Quote:
Originally Posted by stonny86
this is an old post i see, but what if using an ir-camera like the one on the wiimote and a pair of googles with mounted ir-diodes... would that be possible?... i think the wiimote camera can have four points.. so that would be y/x axis....
That would be cool
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Old Dec 12, 2011, 08:47 PM
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Hi Zitron,
My project is to steer a fishing torpedo using a rudder. I have the gyro the servo and the micro controller but I have no idea how to interface micro processor to gyro.

Can you give me some pointers or interface details to typical gyro.

Was impressed with your demo, if I could get mine to work like that I would be happy.
Regards,
Mike
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Old Dec 13, 2011, 08:17 PM
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Originally Posted by scuba7 View Post
Hi Zitron,
My project is to steer a fishing torpedo using a rudder. I have the gyro the servo and the micro controller but I have no idea how to interface micro processor to gyro.

Can you give me some pointers or interface details to typical gyro.

Was impressed with your demo, if I could get mine to work like that I would be happy.
Regards,
Mike
Please find more information here: http://www.arduino.cc/cgi-bin/yabb2/...m=1231185714/0


I have stop this project, because the cost of good quality gyros have come down significantly, there's not much point in doing this any more. You might as well buy a good quality 3 axis gyro from SparkFun for almost the same a mount of money.
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