Blocks sharing loads through differing angles

[TheTreeSpyder]

calcPulleyLoadings

Allows you to alter Load's weight and spread of legs of lines to pulley, as only variables to find static force on friction free pulley. i'll also caution that if working this out by hand in degrees, you can get slightly different numbers, because of calculating by degrees (by hand) vs. radians(by software).

For the players/ code testers; i allowed for floating loads (negative wait) but not angles less than Zer0 nor greater than 180.

For me this isn't about exact numbers, but number patterns; and what to adjust which way to maximize, and when such adjustmeant is most dynamic per your time and efforts; what are the best habits to instill in self etc.

But, also 2 other flings; A)to get a magnified view of the secret life inside of knots, with same angled curves and tensions (just factoring in frictions and compressions etc.). and B)To show how load on horizontal line or swigging/sweating werks. For these are the reverse of the same Math, you are just initiating force from the bend, rather than the end! Thus, the pulley loaded weigh less than load at 170 deg. spread, is shown to there fore have leverage over the line, when the pulley is pulled/not passive responder. The math just shows the points of balance of the forces, that reveals the forces then.

Or sumeeeeetin like'dat.

 

[BobT]

Be aware that in Scenario A the 184 lbs is the total force on the pulley, some of which is toward the trunk. The downward force on the branch is 141 lbs.

If the angle at Block A in Scenario B is 30 degrees, the downward force on the branch will be 13 lbs.

 

[TheTreeSpyder]

The opposite of this, reciprocal math; is hanging weight on a clothesline, speedline, sweating a line. Whereby, you set the force at bend, and the line tension is output. (Where previously we set the line tension with the load, and read
out the forces on bend.

calcLineLeveraging
or
calcLineLeveraging as an excel type spreadsheet

Applied:

sweatingToss-Adkins.JPG

Intense Sweating

Tighten or really tighten.JPG

 

[pancake]

Thanks for the diagrams. Where does the 1.84 come from?

 

[moray]

[ QUOTE ]
...Force = Power x Distance...

[/ QUOTE ]

Spydie, even though I have come to appreciate that you are actually a secret mathematician/engineer and I have learned (usually) to decipher your own private language, this one stumps me. You really shouldn't use the word "power" here, cuz it ain't right.

The convenient language for dealing with situations like this one and most rigging problems is the one mathematicians and engineers use, the language of vectors. Man, if I had your instinctive grasp of this stuff I would want to get my hands on this really simple tool that makes it so much easier to think and talk about this stuff. It is almost a complete end run around the actual math, and you can solve real problems with nothing but a pencil and a ruler!

Even if you blow off the vectors, keep posting; I love your stuff!

 

[TheTreeSpyder]

Thanx, i'll try to make it work; but in a comprehensive imagery expanding beyond mechanical force and to electrical, water, solar etc. It seems we have __________power and it's reciprocal equal to the input Force (less the inefficiency of transfer). Also, to me, a vector is kinda a measure of how much of the total distance-force is inline (1 dimensional/existing in the dimension of the input force), and how much is leveraged(placed not inline, extended to another dimension)? And in simplicity of inline pulleys etc. it worx.

i kinda stumble with the energy thing too; in that by definition the equal and opposite/ lack of energy can give change too. Like cold is the lack of thermal energy, but can still bring change. Now you can truthfully say only in the presence of the energized state(heat) and it's conductance... But still, as a workman/ orchestrator of forces; it could be the lack of thermal energy i'm manipulating to favour. So, in that instance, from my perspective the lack of energy (cold) = the lack of energy X the change it maid??

 

[moray]

[ QUOTE ]
... Also, to me, a vector is kinda a measure of how much of the total distance-force is inline (1 dimensional/existing in the dimension of the input force), and how much is leveraged(placed not inline, extended to another dimension)? ...

[/ QUOTE ]

Each rigging problem needs a vector diagram. This will include a single vector (an arrow with direction and length) for each force involved. You no longer need to use convoluted language about "leveraging", "inline", "dimension", "power", and so on. All the vectors in the diagram add up to zero (unless something is accelerating, which normally is not the case in rigging problems). When you draw in all the vectors for a given problem, and get their lengths and directions correct (usually easy), the problem is solved. All the vectors are perfectly equivalent--there is no talk of one of them "leveraging" another. In the clothesline problem, for example, two vectors are aligned with the legs of the clothesline and one is pointing down, aligned with the load. Their lengths will be different, but they emerge more or less automatically from the diagram. You owe it to yourself to look into this stuff...

Respectfully, moray

 

[Riggs]

After reading this whole post , I will end my life . your fault!

 

[Norm_Hall]

[ QUOTE ]
After reading this whole post , I will end my life . your fault!

[/ QUOTE ]

Of course, we are responsible for your actions. That's the way it should always be.
Scuse me, I'm gonna go juggle some MS200's at full throttle now.

 

[Riggs]

I failed , I'm still alive ! now what ?....

 

[treerxjon]

Let me clarify what I have done here. Of course Spydey caught me on something I didn't think anyone would notice Thanks for keeping me honest.

The math I have done here assumes that there is no pulley sheave that the rope is going around. This would slightly affect the angle of the rope therefore the results.

My goal in this is the same as my old forces on a speedline calculator. Pete Donzelli chastised me on trying to make a calculator that would predict exact forces in a system with so many variables that are not impossible but prohibitive to account for; Things like rope stretch, flex in wood, wind affecting loading and resulting forces.

My goal with both calculators was never to have a treeworker measure angles, plug it into a calculator and be able to say this will impart 1321.3972 lbs of force. My goal was to give people a general understanding on how forces change when you change the system. I can't count how many people thanked me for the forces on a speedline calculator because they said they did not understand how much the angle affects the loading. But by just playing around with some numbers, they could visualize the exponential increase.


Dave Spencer

Dave, outstanding work. I have been struggling with this question. I wasn't initially clear if some force was to be divided due to multiple deviations/how to divide them etc etc. I was barking up the wrong tree. Your diagram cleared everything up and I feel better about the world now. Thank you for all of your time and effort in putting together that spreadsheet. I really appreciate people who have your abilities and are so willing to share them. Have a good one, and thanks again.