The Eggtimer Proton Advanced Flight Computer

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It is on my Christmas list !!!!

Christmas list!, I'm thinking Black Friday, and I was getting ready to order some Quantums and a Wifi Switch this weekend looks like I will wait a bit and save a little extra so I can get a new toy. Especially after totally missing the Labor Day sale due to SodBlaster.
 
Definitely looking forward to this (have been since your test flights at October Skies, I kept silent on the TBA thread :) ), would love to know more about the telemetry option (does that mean it gets paired with an Eggfinder TX to downlink data to the LCD, or something else [TRS or otherwise])? And can you explain "baro:accelerometer off-axis detection"? Could you possibly show a bottom-side photo to show how many parts are on the back? Thanks!!
 
Do you release the cream layer gerber files? For solder pasting? I have access to laser cutter would be alot quicker for me to do it that way
 
baro:accelerometer off-axis detection

Is the off axis detection interpolated from the barometric pressure & accelerometer, or is there a gyro in there???
Orion and I have been working mainly on two stage projects, so I'll be ordering two or three of these :-D
 
Very clean interface that works with almost anything through your web browser. You have got to love the built in tilt-o-meter! look how easy it is to set the outputs to do what you want: View attachment 365665
Where'd Ya get the screenshot? You by chance have a Beta unit? If so, has it flown?
 
Assisted K. building beta unit only. K. will fly it this Saturday at holtville. Cris will also be flying his beta. I expect good reports from them! The Proton is loaded with features at a very low price. Took us about twice as long as doing a Quantum to assemble. This is a great do it all Flight Computer!
 
Could you possibly show a bottom-side photo to show how many parts are on the back? Thanks!!

Happy to oblige... there are a fair number of parts so this is not a beginner's build, it's basically like building two Quantums. All 1206 passives and 1.27mm pitch parts.

Do you release the cream layer gerber files? For solder pasting? I have access to laser cutter would be alot quicker for me to do it that way

Yes, I will be posting the cream files for the Proton on the new web site, which should be up next week.

Is the off axis detection interpolated from the barometric pressure & accelerometer, or is there a gyro in there???

Yes, it's the percentage difference between the integrated accel distance traveled and the filtered baro AGL altitude. It's reasonably accurate in the boost and immediate post-boost phases of flight if you're pointed "up"... good enough for off-axis detection, but it won't tell you which way you're pointing of course. That's why you have an Eggfinder with the LCD-GPS in the receiver. :)
 

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1206?? Come on, give us a challenge!! 0201 anyone?? :D

Sent in an order email, no reply. Waiting for stock? No rush, I know they aren't really available yet. Just wanted to make sure I didn't get dropped in the spam folder or something. :)
 
I think you said none of the protons will ship until the end of November. Will there be a separate post for your annual sale Cris?
 
They should be shipping by Mid-November... possibly earlier. I have a few final shakedown flight tests to do this weekend (nothing flight-critical!), then I have to kit them up. I have all the parts and the PC boards, I just need to mount the baro sensors and flash the WiFi modules.
 
Looks like you might have eliminated one of (my only!!) comment on your products; the mounting hole spacing next to components. I found the Mini, the Quark, and the Quantum all had their mounting holes right up against a component, so that just about any screw used to mount it, it's head clashed with said board mounted component.
 
Single axis accelerometer, then?
Yes, longitudinal (z-axis). A 3-axis accelerometer doesn't really do you any good unless you have gyroscopes too, because the x-y readings will get thrown off by any rotation. If you're rotating along the z axis, you're probably unstable and all bets are off anyway. The accelerometer that I'm using was designed for use in airbags, it has a built in filter and 14 bits of resolution throughout its +/- 120G range. The 3-axis parts with similar G ratings are either prohibitively expensive (for this product...) or have limited resolution (i.e. ST's H3LIS100DLTR).
 
This is great news , can't wait to try one out !

I've always been interested in a speed competition ( MACH MADNESS ) as described in the NAR HPR pink book or personal best - but the only altimeters with accelerometers are plastic, limited on GForce or very very expensive .

From looking at the pic the centered, dual row of terminal blocks should be very solid . From the screen WarnerR posted it looks like a Quantum plus plus plus.

I don't have anything really punchy motor wise right now, but have a K2050-ST , K1103X and H550-ST on back order .. let the madness to begin ...

Kenny
 
Yes, longitudinal (z-axis). A 3-axis accelerometer doesn't really do you any good unless you have gyroscopes too, ...

This product is awesome. Just what I needed to get started with some air starts!

So, z-axis only. Then clearly we are need to get the orientation of the board right on the sled, the sled nice and parallel to the z axis and be extra accurate with the alignment of the chip when soldering. This seems like there could be a lot of error accumulating. Do you have any concerns with the tolerances?
 
Yes, longitudinal (z-axis). A 3-axis accelerometer doesn't really do you any good unless you have gyroscopes too, because the x-y readings will get thrown off by any rotation. If you're rotating along the z axis, you're probably unstable and all bets are off anyway. The accelerometer that I'm using was designed for use in airbags, it has a built in filter and 14 bits of resolution throughout its +/- 120G range. The 3-axis parts with similar G ratings are either prohibitively expensive (for this product...) or have limited resolution (i.e. ST's H3LIS100DLTR).

Thanks for the clarification. Warnerr mentioned a tiltosenser and you mentioned using the difference between baro alt and SSdAdt (can’t type a double integral :). I just wanted to double check.
 
This product is awesome. Just what I needed to get started with some air starts!

So, z-axis only. Then clearly we are need to get the orientation of the board right on the sled, the sled nice and parallel to the z axis and be extra accurate with the alignment of the chip when soldering. This seems like there could be a lot of error accumulating. Do you have any concerns with the tolerances?

For small angles, if you're off by n degrees you can expect about n% of error, and it will all be on the minus side. For most sport purposes, a few percent error is not important... you're just looking for how many G's you pulled or what your maximum velocity was, or detecting boosts-burnouts. The sensor I'm using has a resolution of approximately .015G with an error of +/- .06G, so if you're off by a few degrees in mounting it probably wouldn't even show up.
 
Screenshot_2018-11-04-19-41-21.png
I flew one of the prototype Protons in an evaluation flight with Tripoli San Diego this weekend .

This was just an evaluation flight, utilizing the Proton for motor deploy backup. Very easy to set and you'll be happy to know you can set drogue to apogee or stepped in 0.1 seconds delay after.

Attached is a quick screenshot of the data immediately available after the flight ... Cris says he has a newer firmware available to flash .

Kenny
 
Obviously the Max Velocity and Boost figures are not correct... that's what I was working on. I have a later version that I tested over the weekend, most of the issues are resolved. The killer is long burn motors... it's hard to pick up the boost on them, especially if you airstart one.
 
This product is awesome. Just what I needed to get started with some air starts!

So, z-axis only. Then clearly we are need to get the orientation of the board right on the sled, the sled nice and parallel to the z axis and be extra accurate with the alignment of the chip when soldering. This seems like there could be a lot of error accumulating. Do you have any concerns with the tolerances?

Most ranges encourage or mandate a 5 degree (from vertical) rail/rod tilt away from spectators. Not sure how that factors into the calculations of the tilt logic to determine the go/no-go on firing the second stage.
 
Most ranges encourage or mandate a 5 degree (from vertical) rail/rod tilt away from spectators. Not sure how that factors into the calculations of the tilt logic to determine the go/no-go on firing the second stage.
You'd add 5% to your target figure to compensate. Remember, it's a bit of an approximation anyway, although it tends to be pretty accurate up until several seconds into the coast phase. If you're going to try to get the most altitude possible by letting your sustainer coast for a long time before you light the motor, I'd be inclined to use the altitude/velocity checks instead. Also if you launch away from the flight line and it straightens out and goes more vertical during boost or early coast, the baro altitude will start to converge towards the accelerometer-integrated distance figure. That will reduce the deviation between the two.
 
Telemetry will be in the next release, early next year, it will be enhanced over the other altimeters. There will be a companion LCD receiver firmware release to go with it.

Next release? Do you mean it will be a simple software update? Or will it be something to do with the hardware and it will be an entirely different device?
 
Awesome. Debating what else I need before I place my order .LOL
Just stumbled into the new site too, much better. I see a Bluetooth board, is that new? Seems like I purchased mine separately from Amazon or some such.
 
Nope, we've been selling Bluetooth modules for about 2 years, starting shortly before the Eggfinder Mini came out.
 
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New site's looking good Cris. Assuming you'll have Proton support up soon? Also understand the delay in invoicing lately, looks like you've been very busy. Keep up the good work and all your efforts are appreciated.
 
Obviously the Max Velocity and Boost figures are not correct... that's what I was working on. I have a later version that I tested over the weekend, most of the issues are resolved. The killer is long burn motors... it's hard to pick up the boost on them, especially if you airstart one.

I'm assuming that means that the data returned on boost length for an upper stage will be off but all of the events will work properly? I'm thinking the Proton is just the ticket for a X:G33 2-stage. Booster motor not chosen yet, but will be a 3-grain 29mm CTI.
 
The Proton won't be released until the software is as close to 100% as I can tell. The boost issue was fixed and tested last weekend... there's just one issue remaining, and a little bit of HTML page cleanup.
 
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