IMU for AZ/EL

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VK4CDI
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IMU for AZ/EL

Post by VK4CDI »

Anyone know of a reasonable IMU that could be hooked up to an Arduino or the like and used to provide AZ and EL readout?

Cheers

Phil VK4CDI
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VK4ADC
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Location: New Beith, Qld 4124

Re: IMU for AZ/EL

Post by VK4ADC »

Phil

I am playing with a CMPS10 module that is talking to a PICAXE 20M2 chip, and had it running for the recent Microwave Activity Day, until the IF transceiver was found to be dead on receive and I packed up. I have hard-coded my current magnetic offset (at 10.5 degrees) into the code after it has decoded the data from the module and that is then shown as a TN bearing (XXX.X) on a 20x4 LCD display. I could easily allow for other offsets by simply reading an "offset setting" calibration pot via one of the spare A/D channels and using it to preset a relative offset in 0.1 degree steps ( the offset value is already shown on the LCD display) if I want to.

The CMPS10 might be obsolete now but I bought 2 from a robotics crowd in WA earlier this year and I am currently only using the compass function but the inclination does work too - as tried here in the workshop. It will communicate in PWM, I2C or serial 5V data modes so is quite versatile.

My CMPS10s are in small jiffy boxes that are velcro wrapped {during an outing} onto non-metallic mounting plates up on the booms of the 70cm and 6m yagis (each is on a separate mast and rotator) and I am using serial at 4800 baud back to the picaxe at the distant end (ie. ground level - about 9m of 3 pair cable). The eventual plan is to make up a revision of my existing dual FD rotator controller and then not having to worry too much about precise boom directions when setting up the rotators. [ Currently I have pots inside the rotators themselves so the rotator direction has to be preset then the mast pipe clamped with the yagis pointing in the correct/actual direction.]

Details at http://www.robot-electronics.co.uk/htm/cmps10doc.htm
Doug VK4ADC, QG62lg51
http://www.vk4adc.com
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