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ben5017

Thu Apr 25 2013, 12:11AM

Registered Member #3315 Joined: Thu Oct 14 2010, 04:23PM
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Posts: 156

Max:

no worries.
here are some pictures to keep your interest and motivation in my project. The frame will be cut out on my router I just got operational. I will draw it up on the computer once I know the dimensions of the sub systems and parts. Just waiting on a few more things.

As for my code. I need.

4 stage firing code
- Sensor calibration for each stage (done but needs integrating)
- Limits on max igbt on time for each stage,
- Consecutive coil firing safety
- Debounce each stage

Injector Firing code
- One-shot trigger circuit
- Switch selectable monostable or astable mode
- Debounce
- Adjustable pulse length

Drum Mag
- Fatuba servo code
- Integrate IR reflective sensor servo / encoder haven't decided yet (suggestions?)
- Adjustable sensor sensitivity
- Manual "jog" of a specific degree rotation when button pressed

I hope I didn't just scare you off. I just want to get the main firing code working and add the bells and whistles after

Maxwell

Thu Apr 25 2013, 01:46AM

Registered Member #8497 Joined: Tue Dec 04 2012, 06:24PM
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Posts: 74

Alright.

Can you provide a datasheet or link to the optical sensors you're using? I'm assuming if you're requesting a calibration that you have analog sensors. Are you hard-set on these? I am using two of these:

for benchtop chronograph timing and they work flawlessly...The arduino is simply looking for a 1 or 0 from the sensor (high/low)...I don't have any calibrations. Either the beam is broken or it is not. Granted, you need something a little narrower for fitting over the barrel.

Limits on max igbt on time for each stage
---> I've never had success with an IGBT and the arduino - from my understanding they're somewhat latching. If you know the controls behind triggering an IGBT on/off I can write a brief timer to control it.

Consecutive coil firing safety
---> This can be done by through circuitry - always grounded except when given signal.

Debounce each stage
---> Probably won't be necessary as everything is going to be digital.

One-shot trigger circuit
--->This is where we would use the digital de-bounce and code staging to record code status.

Switch selectable monostable or astable mode
--->I don't understand

Adjustable pulse length
--->Simple.

Drum Mag
I've never done servos. There are tons of Arduino libraries for servos...I've used stepper motors before which are easy. Are you looking for feedback to determine if a chamber is loaded or not with the IR reflection? Manual Jog shouldn't be an issue.

I don't see any problems with these requests.

ben5017

Thu Apr 25 2013, 02:07AM

Registered Member #3315 Joined: Thu Oct 14 2010, 04:23PM
Location:
Posts: 156

max:

I made the sensors out of a IR emitting diode and a IR phototransistor I got of mouser. I will supply the data sheet. They were working great when firing off of my old 2 stage 555 circuit. I am not set on anything but I think mine will do the job. (you have any experience using photodiodes? read they were much quicker)

---> I've never had success with an IGBT and the arduino - from my understanding they're somewhat latching. If you know the controls behind triggering an IGBT on/off I can write a brief timer to control it.

I am having the arduino controlling a igbt driver, not directly to the gate of the igbt. I will send you a link the that data sheet as well

Switch selectable monostable or astable mode
--->I don't understand

Semi auto or full auto

Are you looking for feedback to determine if a chamber is loaded or not with the IR reflection?

that was the plan. open to Ideas. maybe the encoder is the way to go

Maxwell

Wed May 01 2013, 05:57PM

Registered Member #8497 Joined: Tue Dec 04 2012, 06:24PM
Location:
Posts: 74

Hi Ben5017,
While I'm working on this,
If you want to familiarize yourself with basic C++ code, the arduino notebook published at:

provides a lot of good background!

ben5017

Wed May 01 2013, 07:09PM

Registered Member #3315 Joined: Thu Oct 14 2010, 04:23PM
Location:
Posts: 156

I will most defiantly check that out. BTW if you ever need any parts made, I would be more than happy too cut them out for you on my router, as a show of appreciation.. Just PM me.

Maxwell

Thu May 09 2013, 12:44PM

Registered Member #8497 Joined: Tue Dec 04 2012, 06:24PM
Location:
Posts: 74

Hi Ben,

I would anticipate having a functional code tomorrow afternoon.

For clarification again, which model arduino will you be working with?

ben5017

Thu May 09 2013, 04:34PM

Registered Member #3315 Joined: Thu Oct 14 2010, 04:23PM
Location:
Posts: 156

good stuff max, i plan on cutting the frame out this weekend too.

Im using a arduino mega 2560 for now. will probly switch it up to a smaller model as space is in short supply.

Maxwell

Wed May 15 2013, 02:28PM

Registered Member #8497 Joined: Tue Dec 04 2012, 06:24PM
Location:
Posts: 74

Update: code does not function on my mega. (it does on my newer leonardo). But @Ben, no I haven't forgotten about you. Just de-bugging. I have a feeling that the interrupts I'm trying to call are not translating as I expected between boards.

The mega has more interrupt channels than does the other models.

However,
the code for the trigger, armature detection, firing works fine.

ben5017

Wed May 15 2013, 09:39PM

Registered Member #3315 Joined: Thu Oct 14 2010, 04:23PM
Location:
Posts: 156

MAX: Sounds good. Here is a little more motivation. still got away to go .....

construction will be 5mm abs.

What is the most compact arduino you think I could get away with? I want to leave a little room for possible upgrades in the future.

ben5017

Wed May 15 2013, 11:50PM

Registered Member #3315 Joined: Thu Oct 14 2010, 04:23PM
Location:
Posts: 156

update

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