Automatic Deploying Lightning Rod

As hackers, hams, and builders of all sorts of things that go in our yards or are attached to our houses we often encounter resistance from building associations and by-laws regarding what to us are harmless necessities but to others are risks to their sight-lines, property values, or are seen as safety hazards. A student at the Bergen County Academies Mechatronics Research Lab has identified this same issue with lightning rods for homes, monuments, and buildings of fine architecture; people don’t want to add unsightly lightning rods despite their proven protections. Her solution? Detect when a storm is approaching and automatically deploy the lightning rod for the duration of the storm.

To detect the approaching storm she’s monitoring the changing barometric pressure using an Adafruit BMP085 barometric pressure, temperature and altitude sensor (now replaced by the BME280) connected to an Arduino with a motor shield. If the pressure is low and the trend has been decreasing then she pivots the lightning rod up using a motor salvaged from a satellite dish. When the risk abates, she pivots the rod back down again. Admittedly the lightning rod has yet to be attached and care will have to be taken with how the discharge cable is deployed but it’s a start. You can see it in action in the video below.

We’ve seen this issue here before on Hackaday. In one case the hacker had a problem with poorly performing HDTV antennas which they had to cover with unsightly aluminum foil and so replaced them with a much nicer looking and more effective DIY one. What about your own “unsightly” antennas, satellite dishes or other controversial deployments? Have you had to come up with similar solutions? If so, we’d like to hear about them.

37 thoughts on “Automatic Deploying Lightning Rod

  1. This would be a great use for an isolating linkage, else the hit is likely to take the electronics with it.

    While I see quite a few down sides (what if it fails to deploy due to aging, lack of power) I can see this being useful in a place where the aesthetic of not having rods protruding is important.

    1. I was thinking the same thing, but the downside is with the insurance.

      Lightning will occasionally strike “out of the blue”. If your system hasn’t deployed the arrester for some reason, what effect would that have on your insurance?

      I would think the insurance angle would make this sort of system too dangerous to use.

  2. Well, I am sorry, but I hope this young padawan doesn’t get the idea to actually try to “protect” something with this gizmo. In the best case it will fail the mandatory inspection and will invalidate his house insurance, in the worst someone dies and the house burns down.

    I wonder how is he going to actually attach the grounding connection, for example. Oh and having that Arduino and its remote control cable there – a wonderful path for a lightning strike to come down along it straight into his bedroom. There are reasons why lightning protection systems must be built by someone who is actually licensed to do so and the installations regularly inspected – so that any fools trying to “improve them” don’t get to tinker with dangerous stuff they know nothing about.

    This thing is a disaster waiting to happen.

    1. So instead of telling him he’s done great for looking for a solution to a real problem, you’re happy telling him all of the things he’s done wrong. Mentor’s encourage, but instead, you shout from your high tower about his follies. It’s a good thing the Internet wasn’t around when the Wright Bros. were busy toiling, they would have been trolled into oblivion.

      1. It’s an accurate and specific set of criticisms. Mentors may encourage, they may discourage, what matters is they teach and help them to grow.

        You seem the sort of person to hand out consolation prizes, considering this is an application which is perfectly capable of killing someone with extreme ease, destroying homes, starting fires. You know, minor things that only require a licensed and certified professional.

        I’d be fine with this if it had the proper level of isolation, with the lightening aresttors on power lines springing to mind, along with photo-isolation for any electronics. As is, it seems like a truly horrible implementation of an idea born from a truly stupid rule.

        Hopefully this is a proof of concept and nothing further, or else it’s likely to end in misfortune.

      2. The Wright brothers were not exactly held to be the most amazing group of people either. They were trolled and accused of all sorts of things, even without the Internet. They fought lawsuits, well funded competitors, the media and were not exactly always flying high so to speak. Not to mention the injuries that Orville suffered, including a broken leg, broken ribs, and an injured back. On top of his prior ice hockey injuries that caused him to not finish high school. Not to mention the fact that people simply didn’t believe them in their early years that they could actually fly. They had to go to Europe to actually convince people that their flight technology worked.

        All that said, the idea of such a device is interesting but it would be unfair to not point out some of the limitations as well. It needs waterproofing as well as robust electrical isolation as well some method to try to deal with the fact that it is a safety system but also has moving parts that can and will fail or wear out. Unclear that lightning rods that can deploy when needed is the best approach to “improve” existing solid rods that just sit there and always work, with no need for lubrication, moving parts, power or working electronics.

    2. It seems plainly obvious to me that this is just a “Proof Of Concept” that a system can use storm related weather queues to deploy a lightning rod.

      It’s also obvious that the device is not meant to actually protect something due to the fact there is no earth link for the rod, the electronics are not weatherproofed and the whole structure is metal

      An actual production unit would have the electronics and motor inside a weather and lightning proof enclosure with a plastic linkage to move the rod. It would have a ‘Fail Safe’ mode where the system either has a battery backup for power failures or when the power goes out the rod deploys via a spring loaded mechanism which is normally being actively held in the retracted state. The rod would also be connected to earth via a flexible heavy-duty braided copper cable which has been used on lightning rods since for ever.

      I say kudos to the girl for actually having a crack at trying to make something better especially in this say and age where kids are more into Facebook, Snapchat, etc rather than STEM related hobbies. But you know, good job stomping on all that

    3. It can’t *cause* a lightning strike or increase the risk of one happening (which are entirely functions of atmospheric conditions), and it also isn’t going to increase the risk of a strike causing a fire – if a strike causes a fire, *the strike caused the fire*.

      1. Actually it can cause a lightning strike. The idea of a lightning rod is to provide a low resistance path to ground instead of the high resistance of a structure that will heat up (P=I^2*R and all that). It accomplishes this in 2 ways, a metallic conductor and a pointed tip. The pointed tip concentrates the charge of the ground into a small area and when the opposite charge of the cloud is overhead the electric field density is high enough to cause the air to ionize and create a path for the lightning to follow.

  3. Cute idea, but the heart of the matter is a low impedance connection to ground that can take insane amounts of current from time to time. So if the rod must move, what kind of brushes or sliding contacts will be used? And it is almost a given that the control electronics will get destroyed by the first hit. In truth though, my understanding is that a lightning rod doesn’t so much take the hit as bleed things off before a big charge builds up, but when lightning is involved things get crazy and unpredictable.

  4. Should design this to fail safer – i.e. the mechanism should act to keep the rod from rising.
    So when the mechanism fails (e.g. power outage, which is common with storms), then the rod goes up.
    (If it deploys unnecessarily in a power outage, the neighbors probably have more urgent things to worry about than
    the view.)

    (Similar in principle to brake on an elevator or a train.)

  5. Oh for fuck’s sake! Let’s just defang the HOAs already, reafirm private property rights by declaring CC&Rs unenforcable and let evolution sort the whiners out when they fail ti erect safety equipment in the name of their boring, limited view of home beauty.

  6. Interesting idea, but very bad implementation. Lightning protection should be active all the time. Positive lightnings originating very high at the top of the anvil cloud, and due to very high potential difference (over 1 billion Volt) can strike even 50km away from the thunderstorm. The discharge currents are also very high, reaching 300kA. Having lightning protection which gets activated only when a thunderstorm is close will not protect from those long-distant strikes.
    Also, the discharge current path should be as low impedance as possible. The rod should be connected to the grounding wire with a thick and sturdy copper strap, which should be as straight as possible when in deployed position. Each kink or bend will limit effectiveness of the device, and the induced magnetic field may rip the connecting strap into pieces.

  7. I think you did a great job.
    The Idea is sound. more so for older buildings like you said they dont want it to be seen.
    And yes there are things that still need to work out.

    Any protection is better then no protection.

    1. these days there are plenty of actual weather radar data accurate to within a few meters, all of central Europe is covered for lightning strikes and the data is public and only seconds old, last time i was checking the distance to the local light show the pings arrived before the sound had, that was for strikes that were easily visible.

      when data of that quality is freely available it would be a shame to waste time on getting your own, that time is better spent on the unique features for your specific product.

      1. They report strikes after they happen though. They don’t detect sporadic ones that are miles away from what look like storms in advance. Only afterwards. That’s like building a gate that only closes after it detects somebody passes through it first. It’s certainly helpful but I fail to see how that system would assist this much. Again, the best solution is a power free, fixed solution that doesn’t have moving parts or the need to detect an external signal to hope that it deploys before a lightning strike occurs nearby.

  8. I also think it is great idea.

    To all the naysayers out there time to pull your heads out of your …. and take a closer look at the construction.

    It is extremely unlikely to have to take any significant energy if you look very closely you’ll see that the breadboard is positioned in such a fashion that water will pool in the contacts and short everything out and after a week of deployment the corrosion will create irreparable damage the device wont deploy and consequently wont attract lightning, catch on fire or create a nuclear holocaust.

    Another point I don’t see anywhere that there is any expectation for the system to carry any current it appears to be only a method to raise a lighting rod. An external conductor connecting the protection device to ground perhaps. Development of a flexible coupling still needs to happen but now there’s a good use for it when it does.

    Maybe a better use for the concept would be to detect approaching adverse weather conditions and lower an antenna mast during a storm, lightning/strong wind / ice storm.

  9. for safety reasons i would use pneumatics for moving, that way the control would be fully isolated from the rod, also because of possible power outages i would use an backup battery or just an valve that opens when no power is applied.
    to get an low resistance i would try to make the whole thing out of brass so it will withstand corrosion and make some metal wires (idk the right word for it, steel cables or so) connecting top of the rod with the base the base then to ground

  10. How about using a spring return pneumatic actuator?
    Spring return, so that it need to have airpressure to stay down, so in case of a failure or powerloss, the rod would be extended.
    Pneumatic because it does not conduct the lightning :)

  11. There other ways of lightning protection that are used on historic sites. Riming the roof with heavy copper and bonding to lead downs.

    I would want to have sensitive things grounded or isolated during the approach. Real Time Lightning Maps is great at displaying activity.

    My dad once saw a bolt right out of a fishing lake shoot right straight up into a clear sky, must have been one of the lurking super-cells.

  12. Ignore the trolls, as the few projects they make simply blink LEDs on and off. Interesting idea to get around the stupidity of an HOA, and a reasonable prototype as a “make the electronics work” proof-of-concept. Prior to actual implementation, there’s a few things that need to be done:
    1. The electronics need to be isolated from the lightning strike and also packaged in a weather tight housing. Optoisolators and shielded cables are your friends. Think ground path with every connection.
    2. Really large low-impedance ground path to the grounding rod. 8AWG or heavier cable.
    3. Actuation should be as remote and non-conductive as possible. The folks that study lightning use plastic tubing to literally “blow” the ignition circuits on their rockets.
    4. The tip of the lightning rod should be at least 5 feet above the ridge line when extended. Look for pictures of the lightning protection system used during the space shuttle program.

    1. to the other commentors:

      if a home’s insurance is invalidated by this thing, then it’s SURELY invalidated by not having any rod at all?

      if a homeowner’s association controlls a home, then your only a renter, otherwise sue for total ownership of the home you paid for! then jack it up and move it to another property, how’s that for a great view, an ugly hole? doesnt say i cant keep the house when i move…
      (and yes there ARE companies literally moving the house itself)

      if a homeowner’s association says you cant have a ground-rod, sue them for endangerment of EVERYONE living in that “complex” by voiding the very basic law of life, the right to it.
      there might also be by-laws requiring such rods… if your lucky/unlucky depending on if you have a death wish.

      don’t buy a home with fine print such as homeowner’s association, your bound to be bound to the rules of lesseducated andor careless andor control-freaks. they dont care about you because you did not read the agreement and signed it anyway… you KNEW you already work in radio and had to take down antennas from last place… so you should have read your agreement.

      and lastly, if this article is an attempt to disguise a recieving antenna as a lightning rod so your homeowner’s association can read about it, im afraid ive already ruined your cover, sorry, unless this antenna doubles as a lightning rod (they HAVE to, execpt the ones vapourised in a storm)

  13. Smart kid, and a girl on top of that (that is not a sexist or condescending remark, but enthusiasm to see a young girl in the engineering arts).
    However, she has a major design flaw. This device will last until the first lightning strike, or even a substantial step leader, then the electronics and motor are fried. The proper solution is to use a vacuum actuator, and all electronics located away from the rods. Connect all the rod mechanisms with a rubber vacuum line, then all the rods could be raised when the primary sensor (pressure and/or lightning) turns on the vacuum pump. No dangerous voltages could be transferred back into the building via electrical wiring, and all electronics remain safe.

    Also, this is just a proof-of-concept prototype, not a finished product. Naturally it would use a standard Franklin rod, with a large cable connecting them together and to ground. This could be built to hardened industrial specs, and with only one moving part the odds of failure are low. It would have to probably pass UL or other certification process, but if it could make it through all that, she has a winner. I suggest filing for a patent anyway, whether it makes it into production is debatable, but at least she has a patent “notch” in her belt, and that never hurts.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s