Revision to Tripoli Rule Regarding Wireless Remote Switches

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Frederocket

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:)
It doesn't appear the Navy would agree with you.

https://www.navsea.navy.mil/Home/Wa...ane/Resources/SD-18/Product-Archive/Switches/

"Unlike most other electrical parts, switches contain mechanical elements and are therefore subject to failure mechanisms associated with mechanical wear of the switching elements."

"Except for special high voltage and high temperature applications, solid-state switches are inherently more reliable and predictable for long life applications."​
I do not require agreement. My experiences working as a commercial fireworks shooter, limited as it was, tells me all I need to know to understand the need and use of mechanical switches. I have no need for any additional EE theory or statistical data. I know the difference when someone is pi$$&#@ on my leg and when it's raining...:)
 

jbr

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how about using the wifi switch to activate a solenoid that closes the physical switch?
 

Steve Shannon

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It doesn't appear the Navy would agree with you.

https://www.navsea.navy.mil/Home/Wa...ane/Resources/SD-18/Product-Archive/Switches/

"Unlike most other electrical parts, switches contain mechanical elements and are therefore subject to failure mechanisms associated with mechanical wear of the switching elements."

"Except for special high voltage and high temperature applications, solid-state switches are inherently more reliable and predictable for long life applications."​
Thanks for posting that. I noted this paragraph as well:
"High vibration and shock environments of many Military applications, particularly airborne, may cause contact chatter. Such environments may dictate the use of solid state devices, or special mounting methods may be used to minimize vibration and shock amplification."
 

Frederocket

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Thanks for posting that. I noted this paragraph as well:
"High vibration and shock environments of many Military applications, particularly airborne, may cause contact chatter. Such environments may dictate the use of solid state devices, or special mounting methods may be used to minimize vibration and shock amplification."
So Steve, are you now saying we should/will allow solid state switch devices? This is starting to get confusing. Because of your position in TRA, people are listing for guidance. Perhaps I missed something.
 

Steve Shannon

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So Steve, are you now saying we should/will allow solid state switch devices? This is starting to get confusing. Because of your position in TRA, people are listing for guidance. Perhaps I missed something.
No Fred,
We haven't changed the new rule. We're having discussions within the board and with the manufacturers and tidbits like this are added into the stew, but we haven't made any changes. I probably shouldn't even comment when I see something like that paragraph because it could add confusion.
Steve
 

warnerr

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Im having a hard time finding mechanical switches rated for 30g+ TESTED IN ALL DIRECTIONS (even Steves slide switches are in one direction) that wont chatter under thrust.
 

Steve Shannon

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Im having a hard time finding mechanical switches rated for 30g+ TESTED IN ALL DIRECTIONS (even Steves slide switches are in one direction) that wont chatter under thrust.

https://www.nkkswitches.com/pdf/cs.pdf


50G (490m/s2) acceleration (tested in 6 right angled directions, with 5 shocks in each direction)
 

UhClem

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50G (490m/s2) acceleration (tested in 6 right angled directions, with 5 shocks in each direction)
Look at the details: The vibration is at a low frequency and for a long period. What is known as transportation vibration. It tells you nothing about its response to random vibration in flight.

Shock is a mystery. They tell you the magnitude but not the duration or shape. Standard is a half sine and the duration determines the shock spectrum.
 

warnerr

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yes: silicone switches have made me feel safe and eliminated mistakes for me. Doing what i can to try to comply. sad to skip our clubs launch due to not having mechanical switches as i wont do the half way table under the stress of being in a hurry. Getting four or five switches in these rockets is going to be difficult, and be less reliable. The switch leads are appreciated. thanks.
 

manixFan

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So Steve, are you now saying we should/will allow solid state switch devices? This is starting to get confusing. Because of your position in TRA, people are listing for guidance. Perhaps I missed something.
Oh, the irony!!


Tony
 

Pariah Zero

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So Steve, are you now saying we should/will allow solid state switch devices? This is starting to get confusing. Because of your position in TRA, people are listing for guidance. Perhaps I missed something.
Couples therapists and communication consultants often advocate the practice of stating (in your own words) the “other guy’s” position.

The reasons:
• When the “other guy” hears the person he’s talking to repeat his position, he knows the person repeating it is actually listening.
• It also gives an opportunity to correct any misunderstandings, so BOTH SIDES understand each other.
• The whole point is so both sides know the other is listening and understanding.
• It does not mean there is agreement of any kind.

It also typically helps people feel that their concerns are actually listened to, understood, and considered.

We may not get what they want, but we know we weren’t just talking to a brick wall.


For what it’s worth, I understood Steve as saying “I’m listening.”
 

manixFan

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Look at the details: The vibration is at a low frequency and for a long period. What is known as transportation vibration. It tells you nothing about its response to random vibration in flight.

Shock is a mystery. They tell you the magnitude but not the duration or shape. Standard is a half sine and the duration determines the shock spectrum.
This just demonstrates how silly this has all become. Is this really what we have to know to properly choose a switch? Do we all need to become experts in how shock and vibration are measured, and spend hours poring over spec sheets and the shape and direction of G-forces applied to a mechanical switch? What on earth changed to prompt us to have such an existential crisis in switch selection?


Tony
 
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dhbarr

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This just demonstrates how silly this has all become. Is this really what we have to know to properly choose a switch? Do we all need to become experts in how shock and vibration are measured, and spend hours poring over spec sheets and the shape and direction of G-forces applied to a mechanical switch? What on earth changed to prompt us to have such an existential crisis in switch selection?


Tony
That part came from This Thread, from the sidebar about Fireworks vs. the US Navy ( I'm not kidding ).

While I agree there's some absurdity in this thread ( see previous paragraph ) conflating a single viewpoint with the whole conversation yields even sillier results.

You don't have to have an EE to install a light switch.
 

FredA

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Im having a hard time finding mechanical switches rated for 30g+ TESTED IN ALL DIRECTIONS (even Steves slide switches are in one direction) that wont chatter under thrust.
Do we all need to become experts in how shock and vibration are measured, and spend hours poring over spec sheets and the shape and direction of G-forces applied to a mechanical switch?
NO - Don't be silly.
YOU DO NOT need a fancy G-rated switch.
I've addressed this before - read the thread.
 

Frederocket

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Couples therapists and communication consultants often advocate the practice of stating (in your own words) the “other guy’s” position.

The reasons:
• When the “other guy” hears the person he’s talking to repeat his position, he knows the person repeating it is actually listening.
• It also gives an opportunity to correct any misunderstandings, so BOTH SIDES understand each other.
• The whole point is so both sides know the other is listening and understanding.
• It does not mean there is agreement of any kind.

It also typically helps people feel that their concerns are actually listened to, understood, and considered.

We may not get what they want, but we know we weren’t just talking to a brick wall.


For what it’s worth, I understood Steve as saying “I’m listening.”
Thank you Dr., I'll take it up with my therapist.:barf:
 

cerving

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Couples therapists and communication consultants often advocate the practice of stating (in your own words) the “other guy’s” position.

The reasons:
• When the “other guy” hears the person he’s talking to repeat his position, he knows the person repeating it is actually listening.
• It also gives an opportunity to correct any misunderstandings, so BOTH SIDES understand each other.
• The whole point is so both sides know the other is listening and understanding.
• It does not mean there is agreement of any kind.

It also typically helps people feel that their concerns are actually listened to, understood, and considered.

We may not get what they want, but we know we weren’t just talking to a brick wall.


For what it’s worth, I understood Steve as saying “I’m listening.”
Actually, that process is true of problem solving in general... you listen before you speak, or think. The latter is difficult for problem-solving types to do... there's always a tendency to solve the problem while people are speaking, so you have to learn not to NOT solve the problem first or you'll shut out what they're saying while your brain is processing.
 

jbr

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couples therapy thrown into the mix
didn't work with my ex, but I'm happy it didn't as I can do whatever I want, whenever I want, and spend whatever I want on rockets
 

Frederocket

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No Fred,
We haven't changed the new rule. We're having discussions within the board and with the manufacturers and tidbits like this are added into the stew, but we haven't made any changes. I probably shouldn't even comment when I see something like that paragraph because it could add confusion.
Steve
Thanks, I should of remembered, "there has been no changes posted to any of the official TRA Forums". As a result, this thread has no further value added, (for me at least). Although, I did find a good thread locker. I await further announcement on the TRA Forums. Cheers...
 

beeblebrox

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I like to assemble my bay at home, verify the wiring, and then attach charges at the launch site. With many of the screw switches I use, and the form factor of the rockets I use them in, removing the screw with the bay assembled is not practical. I agree that it would be nice that the screw not be loose, but it happens.

At any rate, this debate is largely pointless. The TRA BOD has said what they said and unless there is some kind of modification to their ruling, our only recourse is at the next election cycle. I certainly hope all of candidates make their position known on this.

The only way to insure 100% safety from rockets is to get out of the hobby. Anything short of that is reducing risk, but never to 0.
I agree... My personal choice is a push-on/push off switch. The ones I have take about 700 grams of force to depress. (Measured with a digital scale.) I have the button slightly recessed into the side of the air frame at the tube coupler. Still not 100%, as nothing is... but it would be extremely unlikely for something to hit that tiny 5/64" diameter button at a high enough force to activate it. When the rocket is being transported, the battery is removed/disconnected and no charges attached anyway at that point.
Bottom line, Use common sense... I have seen wiring that would make anyone cringe...Fires have started on model railroad platforms because people can't wire up stuff neatly...
 

manixFan

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NO - Don't be silly.
YOU DO NOT need a fancy G-rated switch.
I've addressed this before - read the thread.
I've been reading and posting all along. I don't recall you or anyone else being given the authority on what switches are deemed safe, apparently not even the board is sure. Everyone at first was 'screw switches', but then it seemed that maybe they weren't so safe or reliable after all. Now folks are talking about how G forces are applied to a switch during testing and whether it's a "half-sine" or not. Look at the discussion regarding how many poles and throws a switch should have.

Yet, no rules have been *officially* changed. Members are making declarative statements about this and that with zero authority over what may actually take place at a launch.
:)

I do not require agreement. My experiences working as a commercial fireworks shooter, limited as it was, tells me all I need to know to understand the need and use of mechanical switches. I have no need for any additional EE theory or statistical data. I know the difference when someone is pi$$&#@ on my leg and when it's raining...:)
And still, in spite of being assured that we are not commercial fireworks and no working knowledge of fireworks is needed, and that we want to keep our hobby separate in the minds of the public and authorities, the most common argument made advocating for the rule change is 'because that's how it is in commercial fireworks'. Yet the mechanical switches used for fireworks are subject to none of the stresses a rocket puts on such a switch. They aren't even subject to 'transportation' vibration.

What with the 'bit-banging' and PnP failure modes, switch chatter and sine waves, screw switches, key switches, slide switches, poles and throws, 'twist and tuck' sure seems like the way to go. At least no one can ask for the data sheet on that.


Tony
 
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GalantVR41062

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We can and have engineered problems for every solution. I am somewhat new to high power rockets, and onboard electronics and energetics. I had a few assumptions with energetics and having some time at the range and research I am working on developing safe practices for my HPR projects.

I come from a background of working on cars, electrical diagnostics and making stuff go fast. I have some advanced electrical testing tools and will be using them to bench test my 2 altimeters that have both a "battery" terminal and "switch" terminals. I would never plan to or think to walk up to the inspection table with my rocket beeping away. I will use a multi meter Snap-on EEDM596D its very similar to Fluke meter, and I have a Snap-on Vantage Pro, a 2 channel oscilloscope. I will be testing a Missile works RRC3 and a ARTS2 with some home dipped ematches and a 9volt battery. I will twist the wires together for a switch and see what the meter shows.

20200227_225615.jpg

I also tested how the multi meter actually performs a OHM check, if anyone uses a meter to check the continuity on your energetics it can be outputting a spike to 1.136 DC volts and leveling off at 0.607 DC volts as I measured here with my multimeter and scope. I understand there is no amps behind the ohm meter check but its still putting voltage through the energetic.

20200227_225903.jpg

First up is the RRC3. I tried to come up with every possible testing scenario on a fully functional altimeter, not taking into account damage, false launch detect etc.

20200227_231345.jpg
with out the ematches hooked up there was nothing present at the energetic terminals as measured across the apogee, drogue and aux +/-. after hooking up the ematch, and battery but no switch continuity (off) I measured 89mv from the ground terminal on the battery to the positive side of the 3 "+" terminals for energetics. I did a ohm check and positive battery terminal goes right to the one side of the switch terminal, then as it goes though a switch the battery power goes back into the other switch terminal and the altimeter turns on. I did a ohm check and the ground side of the energetic terminals pass through a solid state device, so the altimeter does a pull to ground to operate the energetic terminals. So as soon as the altimeter is powered on there is full battery voltage present at the "+" terminal and only a small amount of actual current going through the ematch for a continuity check by the altimeter. it seemed to be less voltage then the 0.607 dc volts I recorded with my meter.

I also tested my ARTS2 altimeter and had similar results. The terminals for apogee and main are not marked +/- on it but the mv measured with just the battery connected no switch was more on the far right terminal, about 110mv spike holding 2mv and became less as I moved to the left, same 110mv spike but holding 0.7mv. I think it is positive then negative from right to left for each energetic.

20200227_234256.jpg

I was able to measure the continuity check from the ARTS2 for the energetics and it was 132.7mv.

I have read the thread and am waiting to hear on a few points. I get that the energetics need to be inhibited. does the switch terminal on my altimeters satisfy this? The voltage present is only in the order of mv and I presume very small amount of current, and this is only present checking from battery negative to energetic positive. if I check across the energetic terminals the voltage is 0 as it goes through a solid state switch, pull to ground, back to the battery. So if the solid state failed, and I powered the altimeter on then pop, the energetic would fire.

I will continue to research, look and learn how to operate onboard electronics and energetics in a safe manner. I will plan to use a reliable switch from battery to altimeters that do not have a switch terminal, and I will perform a physical brake in the energetic "+" lead that I can reconnect with the rocket on the rail but horizontal then activate the main switches to power on the altimeters controlling energetics. I will not be out at a prep area taking apart and re-assembling a rocket "under the gun".

~John
 

Frederocket

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And still, in spite of being assured that we are not commercial fireworks and no working knowledge of fireworks is needed, and that we want to keep our hobby separate in the minds of the public and authorities, the most common argument made advocating for the rule change is 'because that's how it is in commercial fireworks'. Yet the mechanical switches used for fireworks are subject to none of the stresses a rocket puts on such a switch.

What with the 'bit-banging' and PnP failure modes, switch chatter and sine waves, screw switches, key switches, slide switches, poles and throws, 'twist and tuck' sure seems like the way to go. At least no one can ask for the data sheet on that.

Tony

Well, that's my story, as quoted, and I'm sticking to it. You're right to an extent, no data sheet needed for twist and tape--it's an art...:eggnog:
 
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