Ciência e tecnologia

Circular Saw Kickback Killer (We used science to make tools safer) - Smarter Every Day 209

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We're working on a time-series problem called a Sequence Classification. Recurrent Neural Networks called Long Short-Term Memory (LSTM) networks are good for that. It’s what they use for natural language processing because it can remember context from the sentence you’ve just spoken. In this case its used to analyze not just the current timestamp of data, but what has been happening for the last 20 - 250 ms, which helps to reject false alarms.
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  1. Chad Green

    Chad Green

    3 meses atrás

    Also, #gonadularregion is safe!

    • Antonio Claudio Michael

      Antonio Claudio Michael

      11 dias atrás

      +ramzekeleviathan knots in wood can cause kickback

    • jay dellinger

      jay dellinger

      15 dias atrás

      +Schwurbel kickback is the result of the saw flinging wood or the saw it's self back or forward. 🤦

    • John Doe

      John Doe

      Mês atrás

      a riving knife or wedges are far simpler solutions. likely safer too as they wotn fail

    • Photon


      2 meses atrás

      This is a neat idea! If I may ask, what does the hardware look like on the inside of the saw? Does it somehow transmit the data from the sensors or does it run the algorithm locally? Does this massively increase the price of the saw? Finally, how would you prevent it from learning about jostling during shipping? Does it just wait for power to start, and then stay on for some amount of time after the trigger is let go? Sorry, it's a lot of questions. But again this is a really neat example of how ML can be applied to devices we've had for decades. Cool stuff!

    • Shaun Jeffs

      Shaun Jeffs

      2 meses atrás

      It seemed that the built-in saw brake had a significant delay before the blade actually came to a stop. Those blades can be very dangerous even if not spinning at full speed. I'd be interested to know from your HS data whether the brake is capable of stopping the blade before it reaches flesh. It looked like at 80-100 ms, the blade is already in a position to do some damage if you had and ill-placed finger in the blade path. (And yes, I know folks, you should not have your hand there in the first place, but guess what, people do it anyway, and they pay the rest of their lives for it). This is an interesting approach that is quite different from SawStop. You are attempting to prevent the dangerous contact in the first place as opposed to minimizing the damage once contact does occur. There are also many comments on here about the spring-loaded blade guard. I'd like to see in your video how quickly a guard would respond under a kickback scenario. My guess is it probably won't be able to retract in time, as this is a very quick, chaotic event. Good research though!

  2. Mavrick Kolpien

    Mavrick Kolpien

    5 horas atrás


  3. Thrifty Tool Shed

    Thrifty Tool Shed

    5 horas atrás

    Awesome. Love your love for science and how you use that to teach and help others. I can only hope to help in electronics in a very small scale as yours, thanks for helping us get smarter every day and God Bless!

  4. Earl Bramley-Howard

    Earl Bramley-Howard

    21 hora atrás

    1.7k ppl voted this vid down? What? Anything which makes power tools safer ought to be applauded (or even mandatory) Good job.👍

  5. Karls O

    Karls O

    Dia atrás

    I want this on chainsaws. Out of all the cutting tools I have used the chainsaw is the scariest to use even tho there is already a chain brake on it. I think applying it to the chainsaw might be more challenging as it can be used on so many different angles. Will this make a difference to the gyro meter sensor and when it activates the brake?

  6. Simon Sørensen

    Simon Sørensen

    Dia atrás

    a simple narrow metal tooth located just behind the blade, and runs along the cut groove prevents the blade from becoming pinched... and hey presto...

  7. Jacob Taranto

    Jacob Taranto

    Dia atrás

    That is great got to get one for my self

  8. John 14:6 KJV

    John 14:6 KJV

    Dia atrás

    Evenly support the board with with 2x4s running opposite of the cut. Hold on tight and dont stand directly behind the blade. Helps to have both hands on the saw and a sharp flexible blade.

  9. j j

    j j

    2 dias atrás

    In a few years this will be on ALL saws and more, probably OSHA mandated at some point. So cheap and small its amazing. They are going to be rich beyond imagination with this patent. I'm getting my brother one as soon as they come out. He still uses the saw that nearly cut two of his fingers off.

  10. Jenna Easley

    Jenna Easley

    2 dias atrás

    That’s an awesome invention, I really hope tool companies start using it to make their products more safe.

  11. Defy


    3 dias atrás

    If you know how to maintain your saw and you know how to use it you won't have kickback

  12. garycsfunlife


    3 dias atrás

    Don't take off the blade guard and hang on with a little muscle and problem solved and it's free 😁

  13. Jwk Johnston

    Jwk Johnston

    3 dias atrás

    So awesome can hardly wait

  14. Sledge Hammer

    Sledge Hammer

    3 dias atrás

    Great! They'll be even more money now

  15. Orlev Novel

    Orlev Novel

    3 dias atrás


  16. Crazy Funny Cats

    Crazy Funny Cats

    3 dias atrás

    No gloves 🧤 ?7:55? Crazy Russian Hacker has cool dogs 🐕 Safety number 1 pwiowity 😂

  17. Jonathan Mellodge

    Jonathan Mellodge

    4 dias atrás

    Is it a cost effective alternative to common sense?

  18. John Gilmour

    John Gilmour

    4 dias atrás

    How about measuring rate of change of motor current. A ROC 《 x = brake.

  19. smiley


    4 dias atrás

    How much more would it cost.

  20. ChaosTherum


    5 dias atrás

    I want one of these now. My uncle does a lot of woodworking and would love something like this. Honestly, something like this should never be patented it should be open source but here comes me and my open source ranting.

  21. IsaacandCorrine Collura

    IsaacandCorrine Collura

    5 dias atrás

    I’ve been in carpentry for 16 yrs... I can run my cordless skill saw in either hand hanging upside down by my toe nails 30’ up while talkin on the phone (ok slight exaggeration and safety is important to me, but I’m like a 39 yr old essential craftsman!!) and there’s some really dumb stuff out there to make everything so safe you can’t ever get anything done... but THIS IS AWESOME!!! That’s a money maker right there. Love the channel... so do my kids!!!

  22. Bill the traveler

    Bill the traveler

    5 dias atrás

    ☡ I've had a kickback. I didn't like it. Once the thrill is gone then it's time to turn and puke. You are the Heros of Hardware. 👍

  23. Suma_ket


    5 dias atrás

    ok, so i used to work these in europe, and the saw itself is turning the other way around basically...i don't know who would be stupid enough to use one of those..indeed very dangerous.. just make the blade go the other way and its already 50% safer no ? i'm almost a 100% positive it's the first time i see a saw like that spin towards the user..haha incredible.

  24. BomberTheGreat


    5 dias atrás

    Patent and License it! And do it quick before someone is stealing that

  25. robin Pletcher

    robin Pletcher

    5 dias atrás

    Does this happen if the blade spins the other way? Is it a worse cut if it spins the other way? Am I missing something here? The way my skill saw spins it would kick forward, it also has a guard. Never experienced this.

  26. Bob Young

    Bob Young

    6 dias atrás

    some of the best inventions ever were made in a gurage.

  27. Tin Man

    Tin Man

    6 dias atrás

    Perhaps this has already been mentioned, I admit to not having read ALL the previous comments but while this is a great additional safety feature (that is completely transparent to the user in normal use - bonus!) my personal rule as an occasional user is to never let the saw out of the cut until the blade has stopped. My would-be kickback events simply become smoky black areas of the cut as the bound up blade bogs out the saw.

  28. Goldeye666 Hellfish

    Goldeye666 Hellfish

    6 dias atrás

    Mine has a blade guard on it, I'm not sure that I would have to worry about this situation from happening. As soon as the blade gets pushed out of the wood, the guard closes

  29. mike Cummings

    mike Cummings

    6 dias atrás

    Dewalt has this already

  30. Parimal Udapurkar

    Parimal Udapurkar

    6 dias atrás

    Why not simply have the blade turning in the opposite direction so that the "kickback" just pulls the saw further into the wood?

    • mattystewart8


      5 dias atrás

      Because then the saw wants to flip over while youre using it. As well as the saw wanting to come away from you while youre cutting meaning you could loose it

  31. Blue Pearl

    Blue Pearl

    7 dias atrás

    I really could have used that safety when my finger was cut in half & my employee lost his finger due to kickback

  32. Joe Conforti

    Joe Conforti

    7 dias atrás

    Every circular saw I ever bought has a guard on it that keeps the blade from cutting you. If you remove the guard your asking for a trip to the emergency room. This invention is reinventing the wheel. Sounds like you took a $39.95 saw and made it a $59.95. Reminds me of the paperless office.

  33. Dona Harrell

    Dona Harrell

    7 dias atrás

    Holy cow!

  34. Lukas Götz

    Lukas Götz

    7 dias atrás

    Great video, but i dont understand why a neural network would be the right approach for this kind of task

  35. Robert Spencer

    Robert Spencer

    8 dias atrás

    No, for real, this guy deserves to be a millionaire!

  36. SlushEye


    8 dias atrás

    Thats not even a strong kickback, im a carpenter from germany and we have circular saws with 18 inch blades or 45 zentimeters, these saws have a real kickback if you handle them wrong.

  37. I'llOnlyLet UDown

    I'llOnlyLet UDown

    8 dias atrás


  38. philricotta


    9 dias atrás

    I don't make many comments on videos but I had to say that THIS IS VERY IMPRESSIVE. If you never had a kickback event with this option installed you would never know it was even there protecting you....which is the ideal situation for any safety device.

  39. Homeless Canadian

    Homeless Canadian

    9 dias atrás

    Mine comes with something like this- it doesn't have enough torque to kick back enough to be a threat

  40. Kyle Johnson

    Kyle Johnson

    9 dias atrás

    I would not like this it will only make it harder to do your jobe it has a gard ill take my chance

  41. mgunter


    9 dias atrás

    Can't you just tie it to a pressure switch on the guard plate so if it's not pressed down it shuts off faster than human reaction which is about .5 second for NHRA drivers.

  42. natetaylor23


    9 dias atrás

    OK Kick back is not that big of a deal.

  43. Bruce Alan

    Bruce Alan

    9 dias atrás

    So, would this prevent me from dragging the saw sideways, hogging out a lot of material. Im pretty sure it would. This is a weekend warriors safety mechanism. Cool video though! Remember folks, safety is between your ears :)

  44. dracoslayer16


    9 dias atrás

    I like the idea of this but I don't have high hopes of it being adopted into major tool brands. Circular and worm-drive saws have several systems already in place for this issue, plus safely operating the saw calls for always using two hands on the saw, never having anything behind the saw, and always support your work piece. It's even required by law in the US that all saws not only have guards in place but that "any saw ever made" will always have replacement guards available from part manufacturers. Even 25+ year old chop saws you can still get brand new guards for.

  45. Max Chill

    Max Chill

    9 dias atrás

    I'm a carpenter, kickback is user error. Little innovations like this are neat, but every time you experience kick back it is your own fault. Personally I much prefer left sided blades that are battery operated with electric brakes over the old side winders. Your blade should never pinch when cutting plywood, the smaller piece always needs to fall away from you to avoid it.

  46. Dennis Lubert

    Dennis Lubert

    9 dias atrás

    did you seriously blur out the code?

  47. Corey Black

    Corey Black

    9 dias atrás

    Who else can actually smell the wood they're cutting?

  48. Griffin Finnane

    Griffin Finnane

    10 dias atrás

    please make this for a chainsaw

  49. CyBa SinBad380

    CyBa SinBad380

    10 dias atrás

    Why doesn’t it spin the blade the other way so it runs away from the persons body

    • nota virgin

      nota virgin

      9 dias atrás

      Pulling the wood towards you is safer than pushing it.

  50. duitfoto duit

    duitfoto duit

    10 dias atrás

    Riving knife

  51. Abu Bakr

    Abu Bakr

    10 dias atrás

    why the 1.7k dislikes? i honestly dont understand

  52. J B

    J B

    10 dias atrás

    MADSSKMLDBM? Call it Madds Mikkelsen for short

  53. Axl Mizzi

    Axl Mizzi

    11 dias atrás

    Isn't there already a spring loaded guard on them for this reason?

  54. Isch bin de Kalle

    Isch bin de Kalle

    11 dias atrás

    Fake. Completely fake

  55. jackass315


    11 dias atrás

    i love it , i want one , i hope yall get some money for this , this would be great on routers too , dangerous little buggers when you hit a knot , would save some otherwise broken wrists for sure

  56. Tom R

    Tom R

    11 dias atrás

    2:40 are we forgetting the user is still holding the device? Surely the saw can't jump the distances you've portrayed. Either you tense up and of course still hold the saw, or you let go of the button/saw - You can't have your cake and eat it

  57. Antonio Claudio Michael

    Antonio Claudio Michael

    11 dias atrás

    Amazing video guys

  58. Antonio Claudio Michael

    Antonio Claudio Michael

    11 dias atrás

    I think this technology would be amazing in dewalt and Milwaukee cordless brushless circular saws

  59. conexant51


    11 dias atrás

    Watching the first 3 minutes made me think up a much simpler solution, and it's gonna cost just a fraction of this.

  60. Wolfgang Amadeus Van Beethoven

    Wolfgang Amadeus Van Beethoven

    11 dias atrás

    What about the fact, that circular saws, come with a guards. Which is a solution for the problem already and way cheaper to produce. Would love to see comparisons of guards vs your brake. A real test to see if the brake is worth the extra money in development, production as well as at the store for the consumer. Love what you do keep up the good work.

    • Roderick Spiteri

      Roderick Spiteri

      9 dias atrás

      When a kickback lodged the blade in my finger, the saw came at me faster than the guard spring could do its job... lucky the finger bone got between the wide saw teeth and jammed the motor... and only then did I realise I was still holding on to the switch. 5 stitches later and all was good. I was really lucky!

  61. Star Kicker

    Star Kicker

    11 dias atrás

    would be more useful in a chainsaw

  62. Star Kicker

    Star Kicker

    11 dias atrás

    that happened to me while i was 2.5 stories off the ground on a pitched roof with no safety harness or anyone around...but i just forced the saw to stay where it was. because im a man? lol

  63. Patrick Connolly

    Patrick Connolly

    12 dias atrás

    porter cable made a circular saw many years ago(i have one) called a "Speedtronic'' used a microprocessor that regulated the speed of the blade relative to it's resistance in the would speed up or slow down as was necessary and you never had ''kickback'' but it was not popular with most carpenters and they wisely put a switch so they could bypass the microprocessor.....most liked the higher revving unregulated speed that they were familiar with.....i found it to be the best saw i ever used and use but alas it was and is will out cut most of the modern cordless saws still...lotsa torque

  64. Nerevar22g


    12 dias atrás

    i use a handsaw

  65. Number White

    Number White

    12 dias atrás

    I got 5 deep scars on my right thigh due to kickback on one of these saws. Had to borrow skin from my left thigh for 2 of the scars. It's pretty dangerious even for a full grown man. I want you to licence this for tool manufactures. ;)

  66. Jack Caven

    Jack Caven

    12 dias atrás

    Bullshit .... the only reason it's rising out of the wood is because nobody is holding it ! been using them for years and know people who have and ... no problem

  67. Tbnrkaden


    12 dias atrás

    You don’t cut that way

  68. Abteilol


    12 dias atrás

    You first demonstrated with a saw that is missing its blade guard, something most saws these day come with, you then showed a modified saw WITH a bladeguard. why didnt you show kickback behavior with a saw that has the bladeguard installed? is it also not quick enough? i understand that aditional safety is nice, and i imagine the sensor is small enough and cheap that the added safety feature would not impact the final costs of a saw with this feature, still, would like to know how the original feature performs to kickback.

  69. GuiltyMalice


    13 dias atrás

    I’m a little late to this video but guys this is friggin awesome. There are obviously some safety features already implicated in these saws main on being the spring assisted blade guard, but they don’t always save fingers because if they did we wouldn’t here or see people missing a digit or so from any mishaps pertaining to the use of the tool. I myself have luckily stayed safe enough not to have this happen but witnessed my uncle ripping a sheet of plywood and the saw kicked back severing his thumb. Now he can hitch around corners due to it being sewn back on crooked lol. I know it’s awful and I wouldn’t be laughing if it were me. Truthfully I couldn’t laugh about it for quite a while due to witnessing the event first hand. It was awful but I’m happy to say his thumb was saved and he is still very much in the business today as this had happened some years ago now. I’m rambling now so I’ll stop. I just mean to say that this is incredible and if the technology were in the saw that day he wouldn’t be wearing that scar and he’d have to hail a cab like everyone else. Awesome work guys I really hope to see this tech implicated in future circular saws as well as many other tools. Thanks for sharing.

  70. UserName117


    13 dias atrás

    all that matters is 1 thing. How much does it cost to add it to the tool? If it turns a $200 saw to a $400 saw i'll pass.

  71. Bryn Dunbrack

    Bryn Dunbrack

    13 dias atrás

    I know your aware of this already, but you are brilliant !

  72. Jay TX

    Jay TX

    13 dias atrás

    If manufacturers don't snatch that up, would y'all consider offering a service in which we send in our saws and you guys install your device and send the saws back to us? Or is it something you could sell as a standalone product that the user can install? This just seems like an incredible leap forward in the reduction of workplace injuries.

  73. Jay TX

    Jay TX

    13 dias atrás

    5:12 wow great job guys

  74. David Tuttle

    David Tuttle

    13 dias atrás

    The unfortunate thing about this is it’s going to jump the prices of the circular saw like $200

  75. Rafal D

    Rafal D

    13 dias atrás

    This might have been a mistake to pit on youtube, someone could beet you to a patent.

  76. Christoph Rittweger

    Christoph Rittweger

    13 dias atrás

    please google "Spaltkeil Handkreissäge"

  77. ncsugray90


    13 dias atrás

    Seems like something that would fit great into SawStops products, even though it uses an entirely different method of detection

  78. soberhippie


    13 dias atrás

    Just out of interest, why not add a switch that is activated when the saw is pressed to the surface of the wood, in the lower plate?

  79. pyroarchy


    13 dias atrás

    some ppl just dont need to use tools at all lol

  80. mastershake42019


    13 dias atrás

    Best prevention is to never have anything in the line with the front or back of the blade. Having a habit of gripping it good also helps.

  81. Danny M

    Danny M

    13 dias atrás

    grinders are worse.

  82. Robert Hachten

    Robert Hachten

    13 dias atrás

    They make a tool for ripping long lengths....its called a table saw.

  83. RidgeLine Design

    RidgeLine Design

    13 dias atrás

    Nice but you could just not be a dumbass and never have a problem. Why don't you guys work on something important and meaningful like a cure for liberalism.

  84. Dee L

    Dee L

    13 dias atrás

    That wasn't a piece of Plywood, It was a piece of 2x8 Preasure Treated

  85. William Arrington

    William Arrington

    13 dias atrás

    We normally just lay it on the ground ontop of foam insulation. It cant sag and you can walk the middle of the board behind the saw as it goes

  86. Dan R. Graham

    Dan R. Graham

    13 dias atrás

    What is a wide clamp style was applied to the back end of the board to keep it from closing in on the saw blade?

  87. Kevin Scott

    Kevin Scott

    13 dias atrás

    And u do have a good idea sir. Im not trying to interrupted. Clutch. In circulation saw is a dam. Scarest thing in hand..

  88. Kevin Scott

    Kevin Scott

    13 dias atrás

    Tabel saw. Only diamond bits. Cop saw. Radio alarm?. If u go cheap this will be..

  89. Kevin Scott

    Kevin Scott

    13 dias atrás

    I have used a worm saw my hole life. No never kick back. Them says r. No good

  90. Ip sissimus

    Ip sissimus

    13 dias atrás

    Yeah, this would have saved me a few brown trouser events. Now if we can just apply something like this to surfacers and spindle moulders then even I might hit retirement with all of my fingers. I've already mangled the end of both thumbs, and at 46 I've still got way too many years to go. It ain't looking good, people. Not terrible, but not great either.

  91. the D. Willy

    the D. Willy

    13 dias atrás

    Lots of tests run in that garage. You can tell by the blood on the ceiling at 7:59. Great invention, guys! Cool video, too.

  92. Aaron Degerstrom

    Aaron Degerstrom

    14 dias atrás

    I think if you actually know how to use one this is not an issue

  93. Austin Steingrube

    Austin Steingrube

    14 dias atrás

    I guess I'm a bit lost in why ANN were used for this. Neat idea, but this can be done with some pretty simple DSP techniques with much higher certainty without the risk of biasing the behavior via human samples.

  94. Josh Bean

    Josh Bean

    14 dias atrás

    Could something similar be developed for a table saw?

  95. Rogelio Muñoz

    Rogelio Muñoz

    14 dias atrás

    This is cool but I only see homeowners buying this, not any companies or actual Carpenters and that's where the money would be if you make a tool you will need to sell it to industrial companies to make the big bucks

  96. Guns and Wood

    Guns and Wood

    14 dias atrás

    And up go the prices of saws. Yippy.

  97. tankerboysabot


    14 dias atrás

    So lets say i take the saw without being on wood and jerk it forwards would it stop it from working?

  98. The Satanic Gamer From Hell

    The Satanic Gamer From Hell

    14 dias atrás

    But what if the jig saw killer wants kick back in his saws ? ;)

  99. Phillip Roc

    Phillip Roc

    14 dias atrás

    No, you just need to stop holding the saw like your little sister. Is something my dad would say.

    • Tom R

      Tom R

      11 dias atrás

      Exactly, or in this case a free flowing chain with next to no resistance 😂

  100. mhphotography08


    14 dias atrás

    super stupid video

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