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

    Mês atrás

    Also, #gonadularregion is safe!

    • Photon


      13 dias 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

      22 dias 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!

    • Prathamesh Lad

      Prathamesh Lad

      27 dias atrás

      +The Bean Well thanks Bean for the reply. I got it. To be clear I've never used any type of powered saw in my entire life (hand saw is my favourite one :-) . So didn't know anything.

    • The Bean

      The Bean

      27 dias atrás

      +Prathamesh Lad this would make the saw uncontrollable as it would be propulsing itself upwards and over the piece of wood. Sure, no-one is in front, but working with it would be near impossible. Your button idea doesn't seem stupid tough.

    • Prathamesh Lad

      Prathamesh Lad

      28 dias atrás

      +Chad Green Great Project. But my que is Why don't you just reverse the rotation (and cutting side) of the blade ? So let there be a "kickforward" happen (where there is no operator so might be safe) / (Also change button position on palm side so as soon as the machine launches forward our palm seperates from the button) But handle orientation and pressure on the cutting edge ? should be verified.

  2. Talent Acquisition

    Talent Acquisition

    12 horas atrás

    Is it a flight controller in the saw? BTW this video editing is excellent!!!

  3. Sociopath Mercenary

    Sociopath Mercenary

    Dia atrás

    I have some personal experience here. I became careless operating a table saw when I was 16 and ran my left hand through the saw. Detached a couple of fingers and generally wrecked my day but the doctors reattached everything with only the loss of a thumb joint. I'm now an IT professional that uses a keyboard everyday so all ended well. I really like your product. 😁

  4. Bergen Mai Bolsa.

    Bergen Mai Bolsa.

    Dia atrás

    NICE ,im your fan from VIETNAM.

  5. My2CentsWorth1


    Dia atrás

    7:37 Share that with Tommy Caldwell.

  6. Burton's Attic

    Burton's Attic

    2 dias atrás

    I have experienced kickbacks and it is no fun! Don't think any drops of anything came out but flying objects and gonadularregion are really really bad!

  7. Liam Sonmor

    Liam Sonmor

    2 dias atrás

    Need it... now!!!

  8. Gregory Saunders

    Gregory Saunders

    2 dias atrás

    So now you need to put the saw on a rail system so it can't kick up, and then calculate the force necessary to run the saw through the wood with out stalling, then load your rockets accordingly.. and you have to do that now because ... you are the rocket scientist 😎

  9. Jia Jun

    Jia Jun

    2 dias atrás

    lol i really liked the four fingers bit

  10. matkir child

    matkir child

    2 dias atrás


  11. Tim Peterson

    Tim Peterson

    3 dias atrás

    ooOOOoooh! training epochs and NNs, how many layers? cool stuff.

  12. Maximilian Boost

    Maximilian Boost

    4 dias atrás

    You are amazing and your videos are 2 I love the non fake enthusiasm which lets me know that you are really excited about the things you are trying to share with anyone who is interested in science. You are the first one on BR-channel I feel the need to tell that you are doing a great job and that I sincerely hope that you will continue this path. Please excuse my grammar and choice of words if I oversaw any mistakes this isn't my mother tongue. Wish you just the best and an awesome day by realising how you are continuing to make my day which isn't the easiest of tasks at the moment.

  13. Stephen Balon

    Stephen Balon

    4 dias atrás

    This is a very uncommon problem that is exaggerated in the video because.. well obviously, when you take a circ saw attach it to a chain and pin the trigger then turn it sideways in lumber it looks like a disaster waiting to happen. If you operate a circ saw, even one that doesn't have a brake, with a rather dopey level of experience it's nothing like what's being displayed. This is one of those things where, yes, granted the invention works but the problem it's solving isn't a problem that is plaguing trades people. More people in the trades are being injured gradually over time by wearing out their bodies. If you want something that sells immediately make the saw lighter, cut faster/smoother, or more ergonomic. Those are the things trades people are asking for and that's also what they put their money towards.

  14. Brian Hill

    Brian Hill

    4 dias atrás

    This is amazing!

  15. adnane Lebouiha

    adnane Lebouiha

    4 dias atrás

    you guys are awsome !

  16. Paul Bumgarner

    Paul Bumgarner

    5 dias atrás

    Let me know if you want/need investors.

  17. Travis Brantner

    Travis Brantner

    5 dias atrás

    Get ahold of me anyway you feel you can I am very interested in mabey getting in on a part of this

  18. Brad ley

    Brad ley

    6 dias atrás

    Ill buy one from yall

  19. Smile Space

    Smile Space

    6 dias atrás

    Seveneves is a fantastic book! I read it back in 2015 when it first released. It was really good!

  20. paraiks


    8 dias atrás

    Just use the DualSaw

  21. Mary Jane

    Mary Jane

    8 dias atrás

    That's sawsome!!

  22. DailyOoopsies


    9 dias atrás

    Just leave the abbreviation as 'MadSKLS' (Mad Skills)

  23. thr0ttl3j0ck3y


    9 dias atrás

    I just had an idea looking at your thumbnail, how about we try an orbital circular saw? It'd be a beautiful disaster!

  24. Paul-Joseph de Werk

    Paul-Joseph de Werk

    10 dias atrás

    Two microswitches can can do the same work as the "complex sensor" to hit the brake. Also the bowing and binding usually occurs when, you have two sides supports and you are cutting across . You should never support both sides when cutting across. Your demo produced kickback only because the saw was loose and had no one pressing it into the wood, not because the wood bowed inward, since you weren't cutting across between the supports. Just an observation.

  25. Ian Ide

    Ian Ide

    11 dias atrás

    Trouble CUTTING with a saw? This one TRICK saves your manhood!! The only time I've actually seen kickback was improper use of the saw. Not everyone should use power tools and this should be stressed more than saving people from themselves. The idiot that destroys his nuts with a circular saw wont give birth to more idiots....

    • kperry5000


      8 dias atrás

      I don't think that's a good way to look at things. People make mistakes when learning. Heck even professionals can make mistakes. Nobody's born with the innate ability to understand how to use a power saw. People should be able to learn from their mistakes without getting seriously injured

  26. PK B

    PK B

    11 dias atrás

    Wouldn't it be easier to put a button on the flat part of the saw and in the front. The button would protrude below the flat metal and it would have to be pressed in order for the saw to work. Meaning the flat part of the saw is on the wood. So when it kicks back and comes off the wood the button would extend, open the circuit, and kill the motor.

  27. Abhishek Khuntia

    Abhishek Khuntia

    12 dias atrás

    This video was outstanding man, I salute you for making this kind of innovative videos. We also need more on the same..

  28. beachfiredude


    12 dias atrás

    Right on thanks for sharing A Carpenters problem Yup

  29. M. Kharis

    M. Kharis

    12 dias atrás

    that MADsomething is great

  30. Zyrppa


    12 dias atrás

    if i didn't understand things wrong, but wouldn't it be better if the blade spins to otherway?

    • Kytrix


      9 dias atrás

      Yes in Europe the blade turns backwards and no kickbacks.....

  31. Andre Fi

    Andre Fi

    13 dias atrás

    Hey, where did you get the data from?

  32. Kyle Christian

    Kyle Christian

    13 dias atrás

    Destin, this was an awesome video! I’ve been woodworking a long time and love this idea. One tool is like to see this applied to is a table saw. Keep doing tool videos 👍

    • Kyle Christian

      Kyle Christian

      10 dias atrás

      Michami we had a SawStop at my high school and my neighbor has one. What I like about the brake used in this video is it isn’t damaging. When you stop a SawStop you have to replace the cartridge before you can use it again. If that could be replaced with what’s done here that would be a money saver for the consumer (the manufacturer probably wouldn’t want it that way though).

    • Michami


      10 dias atrás

      They have a device on some table saws that have an induction sensor, so that when a had touches the blade, it's stopped instantly with an aluminum brake. I've seen tests using a hot dog, and not a single scratch on it. Honestly though, I didn't know this was a problem with circular saws. I've been using them for decades and never had a problem with kickback. But I'm always extra careful, use all the proper supports, and replace blades before they get dull. Not sure if that's why, or something else.

  33. zztop3000


    15 dias atrás

    I do't get it , kickback? You just hold the chainsaw better, that's it! This is stu*id

    • don trump

      don trump

      15 dias atrás

      zztop3000 this is meant for urbanites who will never use a tool in their life and thus cant see the flaws of the hypothesis

  34. Bijan Izadi

    Bijan Izadi

    15 dias atrás

    Danger Radius

  35. Hangfire-13


    15 dias atrás

    *Doesn't a spring loaded blade shield serve the same purpose at a much lower price point?*

  36. Ben Meyer

    Ben Meyer

    16 dias atrás

    Just put a switch on the base plate. Brake goes on when the switch does not detect the wood. Motor wont even start if the trigger is locked in when power is applied. No patent required, just common sense?

  37. Linkyboy


    17 dias atrás

    I don't use saws, I don't make saws, but this is cool and I want it

  38. gsxrjeff


    17 dias atrás

    just reverse saw rotation

  39. Prince Westerburg

    Prince Westerburg

    17 dias atrás

    Someone else made a plastic fin that stops the wood grabbing the blade. If its that or a computer, what are manufacturers going to choose?

    • don trump

      don trump

      15 dias atrás

      Prince Westerburg exactly. Plus in the example theres a chain substituting your arm. A chain has no push capabilities, only pull. Your arm on the other hand is already making a decent amount of force PUSHING the saw forward

  40. John Farrell

    John Farrell

    18 dias atrás

    Nice job guys. I don't know if anyone actually reads comments so I'll keep this low effort, but if you would like some feedback from an actual 20+ year carpenter let me know. It would be along the lines of: In my experience your scenario is not what actually causes kickback on a real job, though your solution would work in the real job scenarios. The problem you are solving we would call binding. This is easy to over power with a good arm, and plywood does not do this, per your on screen discussion. There are already good solution in effect in chainsaws and table saws. Your approach may be better for hand held saws. Side fact: you were saying humans can't react fast enough to let go of the saw in an emergency. True. But there is an other thing going on. There is something in your brain stem that will not let you let go when the sh$# hits the fan. This is much more of an issue with big, industrial hammer drills. When those things catch and start to spin they will tear your shoulders apart and you can't let go. I always though of this as baby monkey holding moms fur in the trees reaction. It is a real thing. You learn to hold the drill in a way that doesn't use your thumbs so you don't have the strength to hold it if it starts to spin, so you let go thru weakness and save your shoulders and elbows. There's more if you are interested. Good luck with the idea.

  41. jay gareth

    jay gareth

    18 dias atrás

    And I thought a paper cut was scary, who knew there was such a thing as CSK.

  42. NGneer


    18 dias atrás

    Audible keeps putting seveneves in my suggested books. I’ve avoided it simply because I keep seeing it suggested by people I don’t have much respect for. You changed my mind on it. I’ll probably download it tomorrow. Thanks for that. I’m always on the search for a good sci-fi novel. I read around 60 or so last year with audible. I’m running out of good options now though.

  43. Speedy Chicken

    Speedy Chicken

    18 dias atrás

    But no one is putting pressur foward is ut wiuld be more time

  44. Peedlebum


    18 dias atrás


  45. jarrod Alexander

    jarrod Alexander

    18 dias atrás

    Can anybody else hearing nothing but the pop pop pop in the background song??

  46. Davis Tuck

    Davis Tuck

    19 dias atrás

    This also needs to be in stuff like cordless drills. Because sometimes that thing twists around and freakin snaps your elbiw

  47. bowow59


    19 dias atrás

    Fake, the saw don't come to you it goes away

  48. yo boi

    yo boi

    19 dias atrás

    Isnt the same thing with a gas chainsaw

  49. jtan163


    19 dias atrás

    Really curious to know about the sensor you’re using. I fly racing quads and we find that constant vibration an crashing causes our gyros to degrade over time ( they’re designed for cell phones) and we have to replace some of our flight controllers on occasional as they just don’t work after a while.

  50. Stephen Hodge

    Stephen Hodge

    19 dias atrás

    Hey Dustin, I bought "Seveneves", and am really enjoying it!!!!!

  51. Polite Cat

    Polite Cat

    20 dias atrás

    if it falsely trips even 5% of the time, it will get deactivated. its gotta work like 99%+ of the time.

  52. Paul Debaecker

    Paul Debaecker

    20 dias atrás

    I don't know if it is for legal reasons or what, but the circular saw I use runs in the opposite direction (teeth going upwards into the wood). Woudl this system be necessary and would it work?

  53. Antonio Renteria

    Antonio Renteria

    20 dias atrás

    good stuff

  54. Georgy Padalko

    Georgy Padalko

    20 dias atrás

    Cool, modern BOSCH drills have kinda the same thing, they stop and "apply breaks" if a bit jams. Awesome job guys, the more manufacturers have it, the better world will be!

  55. 01Versatran


    20 dias atrás

    Isn't a neural network overkill here?

  56. Ciprian David

    Ciprian David

    21 dia atrás

    just curious... why is this having 1.6k dislike? I mean that mechanism is really awesome

    • Ciprian David

      Ciprian David

      19 dias atrás

      +ensen89 agree but is not about a saw with a riving knife. this is not about how to avoid a problem but how to solve it

    • ensen89


      19 dias atrás

      Maybe because you could just use a saw with a riving knife and don't have the problem? ^^

  57. JronmanBuilds


    21 dia atrás

    hopefully SawStop don't sue you guys because this tech is awesome and needed in every saw.

  58. Son Nguyen

    Son Nguyen

    21 dia atrás

    You guys are freakin so smart. I appreciate the content.

  59. Dennis Sorensen

    Dennis Sorensen

    21 dia atrás

    It should be on ANGLE GRINDERS!!! With a seriously fast acting brake.

  60. tsartomato


    21 dia atrás

    listening WHILE DRIVING???

  61. Caleb Gardner

    Caleb Gardner

    21 dia atrás

    Isaiah 10:15 (SED Translation) Shall the ax boast itself against him who chops with it? Or shall the *MADSSKMLDBM circular* saw exalt itself against the *Destin* who saws with it? As if a rod could wield itself against those who lift it up, Or as if a staff could lift up, as if it were not wood!

  62. Caleb Gardner

    Caleb Gardner

    21 dia atrás

    Verse from the end: Shall the ax boast itself against him who chops with it? Or shall the saw exalt itself against him who saws with it? As if a rod could wield itself against those who lift it up, Or as if a staff could lift up, as if it were not wood! Isaiah 10:15

  63. Daniel Voyles

    Daniel Voyles

    21 dia atrás

    At first glance at 8:00, I thought that was blood on the ceiling from failed attempts.

  64. Travis Romine

    Travis Romine

    21 dia atrás

    Hi Destin, I work for the company that manufactures Milwaukee power tools along with rigid and Ryobi. i have sent this link to my district manager and he said that he would pass it along to the quality assurance representative for Milwaukee. I hope they contact you and get this ball moving.

  65. Pavel Paul

    Pavel Paul

    21 dia atrás

    8:00 the ceiling makes me suspicious. How many volunteers and aliens you've used until the software worked?

  66. Adam Wilson

    Adam Wilson

    21 dia atrás

    This is what riving knives are used for. This stops the timber from pinching on the blade

  67. TotallyOriginal


    21 dia atrás

    Of course his name is Chad.

    • stocchinet


      14 dias atrás

      the virgin kickback sawblade VS the chad programmer

  68. Stefan Tieber

    Stefan Tieber

    21 dia atrás

    Why not just use a saw, with the blade spinning in the other direction?

  69. darkavenger10k


    22 dias atrás

    If you don't have the strength to stall the saw you are using before it kicks back then you shouldn't be using the saw.

  70. Kevin Smith

    Kevin Smith

    22 dias atrás

    It's a good idea but any company that adds it will also add an extra $200 to the price and no one will want to buy it because of the price.

  71. NateLovesToTank


    22 dias atrás

    You’ve also got me convinced to click the bell, what are you going to try and convince me to do next?

  72. NateLovesToTank


    22 dias atrás


  73. hj labs

    hj labs

    22 dias atrás

    I didn't get smarter today ... LOL...

  74. McKevin Dauntless

    McKevin Dauntless

    22 dias atrás

    Circular saw is safe if the person who is using the saw is not dumb enough not to hold the saw properly. I've been using a circular saw for a long time since then i don't have any problem wiit.

  75. Robinson Hogan

    Robinson Hogan

    22 dias atrás

    I made Fusion Power work. So I invented it.

  76. Ромарио МкЛеод

    Ромарио МкЛеод

    22 dias atrás

    Dustin, Chad. Nice to see y'all!

  77. MotoMania


    22 dias atrás

    Hilti got a similar thing. i think atleast. In my old work as a steel worker i used Hiltis circular saws and when cutting things it would kickback but stop right away.

  78. Trey Cranson

    Trey Cranson

    22 dias atrás

    who would thumbs down this video??? saw makers? trolls?

  79. joe cormack

    joe cormack

    22 dias atrás

    he made that incredibly complicated, all he had to do was make it so it would shut off after a jerk movement, you don’t make any sudden movements when making a cut

  80. _V_I_V_I_D_F_O_X_ —3–

    _V_I_V_I_D_F_O_X_ —3–

    22 dias atrás

    Just imagine how the wood feels

  81. Dennis Wetzler

    Dennis Wetzler

    22 dias atrás

    I like your ambition and using your engineering knowledge to over engineer cool stuff. But if the kickback is caused by the cut section of the wood clamping on the blade, Couldnt that be solved by adding say a blade width like stub protruding from the deck to prevent the wood from pinching the blade? My table saw has spmething like this behind the blade to keep the cut straight and prevent pinching of the blade.

    • Dennis Wetzler

      Dennis Wetzler

      22 dias atrás

      Almost like a rutter on a boat.

  82. Laimis B

    Laimis B

    22 dias atrás

    07:59 top left ceiling... where did you hide the body?

  83. Fsac


    22 dias atrás

    +1 for Seveneves. Picked it up on a whim just to use my last credit on Audible, and it turned out to be one of the more enjoyable books I've listened to through their service. So much so that the very first thing I did upon resubscribing was to pick up another Stephenson book.

  84. Marc LeBlanc

    Marc LeBlanc

    22 dias atrás

    Of all the tools in my shop, the one that really scares me when I use it is my circular saw. You guys are on to something. Good luck moving forward. I hope to see this in a future saw.

  85. Christoph Fischer

    Christoph Fischer

    22 dias atrás

    This is super cool. It protects people from severe injuries. Or you could just wedge a little spacer in the gap.

  86. Jonathan Kiser

    Jonathan Kiser

    22 dias atrás

    Gonadular region 😭😂😂

  87. Safir


    22 dias atrás

    Big bandage is gonna censor this

  88. Z M

    Z M

    22 dias atrás

    This will save lives. Great work!

  89. Michael Kane

    Michael Kane

    22 dias atrás

    It's really sad to see the number of negative comments toward this in the comments here. Safety devices are like any PPE. They don't take the responsibility for safety away from the user, but they can make tools dramatically safer to use. I'm not in the market for a circular saw right now, but if one comes out with this technology I will buy it TOMORROW. This has been forwarded to Milwaukee, the power tool company I use.

  90. TheScooted


    22 dias atrás

    Guys - just attach some kind of a button on the saw which will turn it on when a saw touches the wood. When a saw kicks back - the button depresses. No need for human reaction or fancy technologies at all! I mean - why invent a pen that can write in space? Just take a pencil ))

  91. Yotam S

    Yotam S

    22 dias atrás

    Cute cat :)

  92. Ricky Horsburgh

    Ricky Horsburgh

    22 dias atrás

    I like the concept but i think it should be optional to have on or off in certain uses by professionals kick back is expected and grip pressure is increased but it still needs to be cut this would render the saw useless in those circumstances if it cant be overridden. Great for new users or homeowner's and a good back up for pros just needs an override incase

  93. Philip Sparrow

    Philip Sparrow

    23 dias atrás

    I think this is most relevant to chain saws, great idea but applied to the wrong device. keep it up guys. kick back kills.

  94. JAMES! Since the 70's

    JAMES! Since the 70's

    23 dias atrás

    We would need a huge Von Braun space station, or a few of them!

  95. Brew Bear Brewer

    Brew Bear Brewer

    23 dias atrás

    So cool

  96. K0ester


    23 dias atrás

    Worst kick back I've had was on a table saw. Piece of 1x6 kicked back and hit my shoulder. Went through a work jacket, sweatshirt and a t shirt, and gave me a good puncture would with the corner.

  97. Michael Sliva

    Michael Sliva

    23 dias atrás

    Shouldn’t the cut be behind the saw on the handle side and they push it into the wood to simulate someone cutting away from themselves? Especially since it’s doing machine learning on a motion opposite of typical use.

  98. Abram Porras

    Abram Porras

    23 dias atrás

    Is this what killed Johnny Cash's little brother?

  99. LinusDev


    23 dias atrás

    Thats some "cutting edge" technology

  100. Nikita Dubrovskih

    Nikita Dubrovskih

    23 dias atrás

    You're doing it wrong, hold it better. Machine's motor will burn before your bones snap. No reaction required if you know that it kicks.

    • Nikita Dubrovskih

      Nikita Dubrovskih

      23 dias atrás

      "Go to gym" pretty much.

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