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Permalink Reply by Jerry Normandin on June 19, 2012 at 8:17pm

here's the simulator snapshot:

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Permalink Reply by James on June 20, 2012 at 6:02am

Jerry,

careful as that sim is rather old and loiter has gone through many modifications since then!  the latest simulator, which includes the current loiter code is here: http://www.jasonshort.com/

best to do some testing there.

james

 

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Permalink Reply by Jerry Normandin on June 20, 2012 at 6:11am

Wow, good to know!  I was going to fly with my new settings this weekend LOL!

It's a great tool!  I understand why no one wants to suggest settings, only suggest how to derive settings.

If it's wrong and you don't get into stabilize mode quick enough.. bam!

I found out what kind of impact my fiberlass arm/g10 center platform can take.  I am impressed.

I had to replace prop and prop mounts.  But everything else is unscathed!  there was enough flex in the aluminum prop mount shafts and the G10 platform to absorb the shock. I thought I lost it all! Or at least props and motors.  The motors spin fine, still balanced, no vibration or grinding bearing sound.

I am going to use this tool.  I'll post the flight results. I plan on testing loiter, rtl this weekend.

Thanks again for the info!

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Permalink Reply by Jerry Normandin on June 20, 2012 at 6:18am

James,

 I am in the new simulator.  There are two Sim parameters that I don't have a clue to what they are.

Moment and Motor Delay.  How do I find those values ?

Is there a formula for calculating drag?  Is Air Density based on elevation and humidity ?  Is there a chart on the net somewhere ?  And Xsection... what's that.  Everything else I know how to tweek.  I'm going to start from the 3drobotics param file, plug in my platform values and work from there.

Thanks.

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Permalink Reply by James on June 21, 2012 at 2:28am

moment i assume is the moment of inertia of the quad, this is not something that i have fresh in my mind so i cant tell you off the top of my head how to calculate it.  basically though the further from the centre the motors are, the greater the moment.  

as for the motor delay, again im just guessing but this is going to be the time the motors take to react to a change from the ESC.

i assume jason has initialised these at a reasonable value for a "normal" sized quad, and i havent touched these values when playing with the sim.  in fact i havent touched any of the values in the "sim" panel, i think no matter how hard i try there will always be some difference between sim and the real world, so i concentrate more on evaluating the difference between settings rather than the overall result.

james

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