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Spiral_72
04-02-2010, 05:36 AM
I’m working on a brain puzzle with my BS2 at the moment. I have a small ~11oz plane I made from Lowe’s blue core foam. It flies stable and true using elevons (like on a flying wing, two control surfaces used for aileron/elevator). That aside:

I’d like to play with semi-intelligent flight computer. Flying in circles at a set altitude would be good. I suppose it’d be silly to send it off with no override what-so-ever. If I make it RC, how do you think I should transfer control? The best/simplest idea I have is use my gear channel to toggle two tiny relays. The relays would normally (de-energized) connect the RC receiver to the servos. Once switched it would move control to the onboard BS2…… the PWM signal to the servos would switch through the dry contact on the relay.

What do ya’ think about the transfer of control?

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"puff"...... crap, there went another one.

Spiral_72
04-02-2010, 05:49 AM
as a note, I've found a board that does what I want for ONE HUNDRED DOLLARS! not only that, it's heavy.

Another person run the RC servo commands into the microcontroller and "simulated" them back out while in RC mode.... Pretty dangerous.

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"puff"...... crap, there went another one.

W9GFO
04-02-2010, 06:12 AM
Hook each channel to a pin on the BS2

Use PULSIN to check the state of each channel
If the gear channel is active (you want to have control) just send the exact same values out to the servos as are coming in. If the gear channel is off (autopilot) then go into an autonomous subroutine - be sure to keep checking the gear channel though.

With three PULSINs and two PULSOUTs you will want to reduce the standard PAUSE 20 to about PAUSE 10 or maybe even less.

Rich H

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The Simple Servo Tester, a kit from Gadget Gangster. (http://www.gadgetgangster.com/206)

Post Edited (W9GFO) : 4/1/2010 11:25:38 PM GMT

Spiral_72
04-02-2010, 12:23 PM
Yes, that'd be the absolute simplest and I saw that method in my research, but I considered if something happened to the Stamp, lost power / program locked in a loop, I'd loose all control. It'd be nice if the flight control was independent of the RC control.

Or should I even worry that much?

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"puff"...... crap, there went another one.

W9GFO
04-02-2010, 01:25 PM
True that there is many ways to have problems. In your case, a small foamie, it seems an acceptable risk for the sake of ease, maybe you feel differently.

In my case I used a much larger Sig Rascal 40 that was converted to brushless power. I used a BS2, thermopile horizon sensor and a GPS to control an auxiliary rudder which, if gone awry, could be overpowered by the regular controls. Like you, I did not want a programming hiccup to cause a loss of everything.

Rich H

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
The Simple Servo Tester, a kit from Gadget Gangster. (http://www.gadgetgangster.com/206)