Real Mechanical Advantage - Testing in real world application

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  • เผยแพร่เมื่อ 24 ธ.ค. 2024

ความคิดเห็น • 46

  • @TheRopeAccessChannel
    @TheRopeAccessChannel  2 ปีที่แล้ว +6

    Did you know using a descender as a PCD actually reduces the actual MA by 1? Ideal MA 3:1 (no CD) become a 2:1 in Practical MA. That in turn in ACTUAL MA becomes even less!! Did you know?

    • @ianrobinson8518
      @ianrobinson8518 10 หลายเดือนก่อน

      Effectively a locked PCD eliminates the last leg of rope. Thus a 3:1 (theoretical) z-rig becomes a 2:1 simple system but a 9:1 double z-rig becomes a 6:1 (=3:1 x 2:1) system. An open PCD will deliver about 30% efficiency (according to your earlier video). So it's worse than a biner but still adds a little MA.
      A great video! I attempted to backsolve for the efficiency of the biners using a general formula I devised and came out roughly to 50% as expected. Great to see reality mimic theory! Haha.

  • @kamilniski4134
    @kamilniski4134 ปีที่แล้ว +1

    Hi Alex! Thanks for your effort making these videos. It helped me a lot understanding how pulley systems work. Keep doing awesome work!
    I have small comments though.
    I'm not 100% sure but i've noticed problems with the experiment.
    First one is the misplacement of "Grab" LS3. It did not measure the force of whole system. In the video it measures 2:1 subsystem on z-rig and 6:1 subsystem on 9:1 rig. It should be placed between the load and the last line clamp.
    Second one is slightly wrong actual MA calculation. In video the AMA is calculated as ratio between value from "Grab" and benchmark value. It should be calculated as ratio of output to input on the same rig. For example: in last measurement it should be 100/65 = 1.5 AMA

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  ปีที่แล้ว

      Thank you for the comment. I think you misread the values. I am only interested in the real world input values. Meaning with the friction of the first change of direction when lifting the load in a 1:1 my initial input is 118kg. That is the force I calculate against. Not 105kg. The grab LS3 is measuring my input where I pull on the rope. Exactly what I want.
      Next I am interest in what I need to actually put in to move that. The Ls3 in the middle of the system is there to show loss of force due to friction in the system.
      So the AMA in your example is not 100/65. My calculation is 118(or 120 for ease of calculation divided by the required input to move that load. 120/65=1.8 AMA.
      Do you understand what I mean?

  • @Gogubutelie
    @Gogubutelie 2 ปีที่แล้ว +1

    Thanks!

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว

      Welcome! Thank you 😃😃😃😃🙏🏼🙏🏼🙏🏼

  • @aerialrescuesolutions3277
    @aerialrescuesolutions3277 2 ปีที่แล้ว

    Those numbers are wild. I usually only use pulleys or large-diameter blocks for this type of stuff. I would not expect a carabiner to be used for this. Carabiners attach the pulley or block to the anchor. Great video, thank you.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว

      Thanks Jim, It happens more often than i'd like to see in training. Only once a 9:1 with only biners but that 3:1 with biner as CD happens quite often..

  • @MrDavide1095
    @MrDavide1095 ปีที่แล้ว +2

    Nice video! I was looking for this tests, expecting them from How2not. I guess it would be interesting to test how angles affect forces while pulling. Thanks again

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  ปีที่แล้ว

      That’s an interesting question. Not sure how to film that and relate to a practical situation yet. I do use a vector pull on tight lines quite often which would be the same principle

  • @maldonadorodrigo
    @maldonadorodrigo ปีที่แล้ว +1

    Hey dude. One question, shouldn't the Line Scale be in front of the grab to measure the total strength of the system? In this assembly, the third line (when 3:1) of the system is not adding to the line scale measurement. Have you already carried out tests in this configuration I mentioned? I hope to contribute and answer my questions. Congratulations on the video, I can only imagine how much effort you put into making it.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  ปีที่แล้ว

      First of al thank you!
      Unfortunately, I do not know what you mean?
      I am measuring how hard I need to pull to move the load. So the linescale is in the right spot. Can you try and explain it a bit better?

  • @endikaheredero3956
    @endikaheredero3956 2 ปีที่แล้ว

    With subtitles im just your fan number one, my master 🙌🏼🙌🏼🙌🏼 😂

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว +1

      Awesome!! That is good to know. Ill be adding them to all the video,s but that will take a few months I think!

  • @paulnosek714
    @paulnosek714 2 ปีที่แล้ว +1

    Thanks for doing the videos man ! Gets the brain going

  • @EricNietofilms
    @EricNietofilms 2 ปีที่แล้ว

    I love this videos! hope to see much more of them! 😃

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว

      Cool thanks man!! Is there anything you would like to see?

  • @paulnormandy6247
    @paulnormandy6247 2 ปีที่แล้ว

    Great video. This would be a great setup for demonstrating the “pulley closest to the puller” tip as well!

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว

      Thanks.
      That is what test 7 and 8 (I think) sort of show right. it went from being a 1:1 to being a 1,3:1. That is just in a 3:1 with CD system. In more elaborate pulleys systems that difference adds up through the system and the results will be better to see

    • @paulnormandy6247
      @paulnormandy6247 2 ปีที่แล้ว

      @@TheRopeAccessChannel you’re right! I didn’t catch that at first, had to look at your summary chart a second time. Awesome video!

  • @robbesymoens4005
    @robbesymoens4005 2 ปีที่แล้ว +1

    Loved the video! Did you use a certain program to make the pictures of the rigging you did or just found them on the internet?

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว +2

      I used a vrigger for that. I am finalizing an affiliate deal that will give my viewers 10% discount and I’m making a dedicated video to that as well. Great program i have been using since 2015👍🏼
      So if you are interested, wait a little until I have released the code and you see a bit more of the program. By then I should have my link and code and you can buy with a discount😉👊🏼

  • @schullerplx
    @schullerplx 2 ปีที่แล้ว

    Hey, mate. Awesome videos! Im enjoying your content. Keep on!
    I have a doubt, could you help me. I was wondering, when you rig a hauling/lowering, what would you do in case the main line snaps and the asap (backup) is activated? The casualty/load would be hanging on the backup line. How to go from there?
    Thanks a lot!

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว +1

      Thank you 🙏🏻
      To answer that fully in here wont work for me. But good news is there will be a video about it at one point..
      The short answer….
      As usual the answer is, it depends.. Lets start by preventing it using a ttrs type setup. Then there is also the question why did it break…That would dictate what to do next. You’re also dependent on what gear you have on you. But if we are talking about the most basic setup, you can use the now useles i’d and clamps and pulleys of that broken system to continue the raise on the backup line. Usually you can install that right above the asap. Yes it would be one rope but the shit is way past the fan so time to make do. No real good answer here as there are so many variables.

  • @felipevelasquezmarv2878
    @felipevelasquezmarv2878 ปีที่แล้ว

    Excellent video, do you realize that when you changed the winch of place yow have created an angle and it affects all the following results?

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  ปีที่แล้ว

      I don't think I understand what you mean... I don't see what you mean with "created and angle"
      The winch had two places mimicking where you would be standing or pulling from in a given pulley system setup. So yes of course that changed the following results. That is the whole point right? When you use a CD you add a point of friction and the results change. Is that what you mean?

    • @felipevelasquezmarv2878
      @felipevelasquezmarv2878 ปีที่แล้ว

      @@TheRopeAccessChannel I'll try to explain but it's difficult for me because I don't speak English very well, in the first position the rope that enter in the winch was in parallel with the others ropes, in the second position when you change te position of the winch there's an angle between ropes and it makes the winch do more effort, I think the idea in this experiments is try to keep the same conditions to get the best results. Anyway I like to much your videos thanks.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  ปีที่แล้ว

      @@felipevelasquezmarv2878 I don’t see what you mean. The ACX or pulling hand only had 2 positions. One is pulling with the load and the other against the load (direction) mimicking a change of direction. Besides that there is no angle or deviation to speak of.
      We get consistent and comparable results with what I am trying to measure. A pulley system and a pulley system with a change of direction.
      With a CD the winch needs to pull more yes and that is exactly what I am trying to measure. I am testing what I want to test and consistent within the two possible setups. Do you see what I mean?

  • @jetseverschuren
    @jetseverschuren 2 ปีที่แล้ว

    Super vet. Ik had niet verwacht dat je dit al zo grondig had getest, zo kort op je vorige video. Als je nog dynamische (val) testen wilt doen, ik heb Ryan van HowNot2 geholpen met een systeem dat tot ongeveer 100kHz gaat, dat is grofweg 100x sneller dan de LS3, wat voor statische materialen prettig kan zijn.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว

      Thanks Jetse. Ik heb je naam wel eens voorbij zien komen ergens ;-). Ik hou het in gedachte 😃😃 Thanks

  • @ridermak4111
    @ridermak4111 5 หลายเดือนก่อน

    You have 2 tensions going into the final rope grab. Only one of those is from the load cell. Should the load cell be beyond the rope grab so that there is a final single tension on both ends of the load cell ?
    With no line bypassing the load cell like it is now.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  หลายเดือนก่อน

      I am not sure I understand your question...
      The only interesting value is how hard I need to pull. So that is the one that matters to me. The LS3 in the middle of the system (grab) is just for interest and to see what gets lost in the system.

  • @ukaszszynkowski8960
    @ukaszszynkowski8960 10 หลายเดือนก่อน +1

    Damnnnnn greaaaaatttt!!!

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  10 หลายเดือนก่อน

      Thanks man 🙏🏻🙏🏻🙏🏻🙏🏻

  • @nigels6472
    @nigels6472 6 หลายเดือนก่อน

    Wouldn’t your results be closer to a theoretical 3:1 if you moved your load cell for the “grab” after the rope grab itself? Where you have it setup is showing the actual results of a theoretical 2:1, is it not? You’re not reading the added tension from the third leg of rope in your 3:1 system?

    • @ianbrown_777
      @ianbrown_777 หลายเดือนก่อน +1

      @@nigels6472 The AMA figures in the table are derived from the measured load 'weight' of 118 units (at 2:26, 1.18kN) - not the ratio of the load cells - so the actual overall MA. I think its a good test. I think he's demonstrating a real world setup using PCD's, showing their relatively large amounts of friction. In the first tests (with no CD), the actual input and output of the various moving pulleys/carabiner are shown directly. The rest we can calculate: the tension in the second leg of rope, pulley efficiency, its local MA if we want and also the tension in the third leg of rope.
      So in the first 3 tests we see the load almost totally supported by the first two legs. That third leg is doing almost nothing. It must be almost slack. In the test 4 we see 100 at the pulley output so that third leg coming out of the Pro Traxion must have 18 units. In that instance it seems to be a bit over 50% efficient.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  หลายเดือนก่อน

      Yes and that is why there is a LS3 monitoring as hand, the only interesting real world value for me is what the "hand" says. How hard do I need to pull on the rope to move the load. The "grab" is just because I was curious how much tension there was at that point in the system.
      Also I did like 15 tests. Can you specify which one confuses you?

  • @dakotafrantz4179
    @dakotafrantz4179 2 ปีที่แล้ว +1

    So did you prove that 3:1 using pulleys only translates to 2:1 and that 9:1 only translates to 6:1 in real life

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  2 ปีที่แล้ว +1

      Not really. I only showed at that moment with the gear I was using that a Ideal MA 9:1 with the most efficient pulleys I had there was an actual 6:1.
      And with an I'd in an Ideal MA 3:1 was actually whatever was on the board. It slips my mind right now. Probably 2:1 or less. The results are on the website

  • @ianrobinson8518
    @ianrobinson8518 10 หลายเดือนก่อน

    Your table of results has an error. The 3rd last line should say "Biner" under the Grab column. You also didn't test (or show?) a Rescue all round---only a Pro Traxio all round (2nd last row).
    I also calculated the PMA using efficiencies 90% pulley, 50% biner and I'D 30%. The results were consistently a little higher than the AMA as expected.

    • @TheRopeAccessChannel
      @TheRopeAccessChannel  10 หลายเดือนก่อน

      Correct, I did not test the all rescues around. I think we always need a progress capture in the system. that is why I chose the Pro Traxion. It was one of the most efficient pulleys there anyway.

  • @evertongatto8944
    @evertongatto8944 2 ปีที่แล้ว

    👏👏👏👏🔝

  • @alexiroccos5454
    @alexiroccos5454 2 ปีที่แล้ว

    Well done! You need an assistant.