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so from the 4000N longitudinal force you get
4000N longitudinal and 3000N lateral ???????
I think that you will find that the resultant longitudinal forces will only be 1000N.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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so from the 4000N longitudinal force you get
4000N longitudinal and 3000N lateral ???????
I think that you will find that the resultant longitudinal forces will only be 1000N. I didn't use a 4000N input. I used a 100kg mass bashing into it at 40m/s. But yea those were the average forces at the supports. Go back to the FBD to see if it should be 1000N or not. No point just making up numbers because they feel good. Also no point making up a 'law of conservation of magnitude of force' when none exists. This mechanism has a mechanical advantage or disadvantage, so you can tune it to give whatever horizontal force you want. You can have 1000N if you want, but it won't detract from the 4000N pushing backwards.
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100kg mass bashing into it at 40m/s. thats 4000N isnt it? at least it is if the mechanism stops the 100kg mass in 1 second.
whats the name of the program you used?
the reason I say 1000N longitudinal is because you say 3000N lateral. you cant have a reaction larger that the action.
for every action there is a equal and opposite reaction.
the cosine of 45 degrees is 0.7071
4000N * 0.7071 = 2828.4N this should be the resultant lateral force that the slider feels.
of course you would divide that by 4 when using 4 legs , you can use 1 to get the total.
pretty close to your 3000N !
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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100kg mass bashing into it at 40m/s. thats 4000N isnt it? at least it is if the mechanism stops the 100kg mass in 1 second.
Yep, on average it is. It doesn't apply a constant 4000N. whats the name of the program you used?
LISA www.lisa-fet.com the reason I say 1000N longitudinal is because you say 3000N lateral. you cant have a reaction larger that the action.
The 'action' on the left spring is -1500N, the reaction applied by the spring is equal and opposite, +1500N. Similarly for the other spring. Again, there's no reason to conserve magnitudes of forces. You can easily apply 4000N longitudinally and get 10,000N sideways. It's just mechanical advantage. for every action there is a equal and opposite reaction.
Yes, opposite, not sideways.
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the cosine of 45 degrees is 0.7071
4000N * 0.7071 = 2828.4N this should be the resultant lateral force that the slider feels.
Can you go into more detail? You seem to be considering both legs together, as well as the input force. It's a bit confusing. But I think the general idea of calculating components is right. Hey by the way, do you tend to edit your messages, adding extra parts, and turning off the 'mark as edited' option? I'm not complaining, but I often find your messages are different after I've replied to them. Or maybe it's a bug in the forum?
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yes , opposite and opposing. thats why you cant have the full 4000N , its not opposite.
the forces start at a 45 degree angle. and the angle decreases.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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yes , its always a work in progress , you should usualy wait a few minutes to reply.
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yes , opposite and opposing. thats why you cant have the full 4000N , its not opposite. Word games mean nothing in physics. FBDs aren't ambiguous. You really should use them. They make it clear what all the forces are.
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if you can agree to the above , then I will add this to my program to return the resultant forces using distances and time for each degree. in the above none of the resultant forces are above the 4000N applied , so I trust this. what I meant in saying you cant have the full 4000N was that the longitudinal direction that you are claimimg that the 4000N force would be in , would not be 4000N at no time durring the cycle. it will always be from 45 and decreasing as pictured above.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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Yea those diagrams perfectly correct in themselves.
But it's not 4000N along the diagonal member. It's 4000N longitudinally at the input, so that direction change has to be calculated in a similar way.
As well it's split between the two diagonal members, so they only get half each.
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I was just showing how the forces would direct through the point that you used , of course the first angle from the input point would also be at 45 degrees.
you didnt include that either did you?
yes I was intending to include 4 legs in the program and using all elements involved , we can call the sliders massless or we can give them a mass , also friction in space would be the result of forces causing objects to rub against each other , so there will be friction should we use a friction coefficient also or can we say that friction is negligible for now?
So if you can agree to this then I will put these into the program Im building.
do you think you could help with a spring coefficient to use?
I asked earlier but you didnt reply , what did you use in the program you used?
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I was just showing how the forces would direct through the point that you used , of course the first angle from the input point would also be at 45 degrees.
Yea I agree with what you did and that the first angle would be the same. Just not with using 4000N on the diagonals. do you think you could help with a spring coefficient to use?
I used a spring constant of 70 N/m for each spring. Everything massless would be good. And everything frictionless. Those two things can always be made arbitrarily small in real life.
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Im almost done with the program , but I have to say its not looking good for your side , LOL.
well I am done with it mostly , the calculations are done I just need to make a postable text file with it that shows the results.
the 70N/m stops the mass to quickly using a 20 meter stopping distance , it stopped in less than 1 second.
and in a 40 meter stopping distance it stops in 5 meters.
so I need to find a useable stopping distance and spring co efficient to use.
I want to make sure its all right before I post the results anyway.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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well I am done with it mostly , the calculations are done I just need to make a postable text file with it that shows the results.
Remember I won't be able to trust your computer results any more than you trusted mine. You'll have to describe the calculations in such a way that I can easily check and reproduce them. What are the equations? And why not do the static calcs anyway? We never resolved even the static case, so I don't expect any dynamic analysis to have much purpose at this stage.
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good point
maybe I should include the equations in the readout that I make.
I havent determined the best arm lenght and its initial and final angle yet , so when I do then I can include the readout portion within the program.
Im using the spring co efficient as a resistive force. and then I subtract that force from the 4000N before continueing to the next set of calculations , so it should be pretty precise.
now the more sets of calculations that I allow the program to perform , the more precise the results are.
so it will be awhile , meanwhile I have recieved my new starter for the hydrogen engine im building. I purchased a old 15 hp engine frm the salvage yard and am rebuilding it to use HHO only !!!
if it works well enought I will want to find a generator head to attach to it , and then get my free energy.
it has a built in generator that charges batteries and powers lights and stuff on a riding lawn mower and this generator might just make all the HHO it needs to run.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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I havent determined the best arm lenght and its initial and final angle yet , so when I do then I can include the readout portion within the program.
Don't bother optimizing it. To prove me wrong you only have to show that either of these claims is wrong, even slightly: 1. The average of the total force applied to the pipe is identical to the average force applied by the mass. 2. For a 100kg 40m/s mass, the average force applied by the mass is 8000Ns / turnaround time. Im using the spring co efficient as a resistive force.
It isn't a force. You have to multiply it by the amount of spring deflection to get the force. starter for the hydrogen engine im building.
Cool. I'm glad you're actually trying it. I just hope that when it fails you don't make some excuse about too many strokes or not fully using the intake vacuum or whatever.
Last edited by kallog; 07/19/10 11:26 PM.
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1. The average of the total force applied to the pipe is identical to the average force applied by the mass.
2. For a 100kg 40m/s mass, the average force applied by the mass is 8000Ns / turnaround time.
I suppose you mean the average force applied to the pipe in the longitudinal direction in #1 above. because alot of the force is being applied in the lateral direction. and the force that is being applied in the longitudinal direction is being applied as a torque or twisting force that stresses the pipe along its sides , therefore that force can be dampened also resulting in even less longitudinal force. in #2 above it is 4000N that is required to stop the mass in 1 second as the mass stops , however it seems that the springs do not compress enought to return the mass at 40 m/s in the next second , so the total will be less than 8000N. alot of the force is lost through the angles and in the twisting torque through the sides of the pipe. but dont worry Im taking everything into consideration. maybe I should make another drawing or two to explain this better.
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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I suppose you mean the average force applied to the pipe in the longitudinal direction in #1 above. because alot of the force is being applied in the lateral direction.
That would do too. I actually mean the entire total force. All lateral forces cancel out in the averaging operation, so only the longitudinal component contributes. pipe along its sides , therefore that force can be dampened also resulting in even less longitudinal force.
Equations not words! If that's true, I'll admit I'm wrong, and you'll be confident that your machine will fly. m/s in the next second , so the total will be less than 8000N.
OK. I still stand by 2nd point, except I realize I used the wrong sign convention. Should be a negative in there. I'll add a more general #3 to allow for your new situation: 2. The average force applied by the mass is F = -m * (v_2-v_1) / turnaround time. Where v_1 is the initial velocity (-ve for backwards), and v_2 is the final velocity. This allows it to come out slower than it went in. I've also made some unstated assumptions in how the averaging is done. But I don't think it'll become important unless you have masses inside the device. The averages should both be made over the same time period and it should be one in which all forces occur, even if that's longer than the turnaround time. maybe I should make another drawing or two to explain this better.
You should show some equations or even code. Actually I'm amazed you're programming a dynamic response solver. Engineering students do that in their final year. You really should do a FBD or any kind of static analysis. If there's mistakes in that then surely any work on the program will be a waste.
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You should show some equations or even code Im doing this in vb6 , because its much easier , do you have vb6 or higher? if you have higher I could probably upgrade the project to fit in with your compiler. or just copy n paste the code and you can figure it out. I have to warn you though its not pretty and I use a few tricks to speed things up a bit.
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Oh ouch. I've had plenty of bad experiences with people trying to optimize VB6 code (don't do it!!!). I think I'll pass. At least until it's complete.
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