Here's what  I have to say: You might not be lifting the weight at all. Your precharge is doing most of the "heavy lifting". Your added water is only adding a small amount of lift, enough to allow the precharge's "counterbalance" to raise the weight upwards.

Your risers/weight are actually floating at the start, they are just in a low position, with the precharge stored buoyancy and gas pressures acting as a compressed spring. When you add the water in the tube, you are adding enough float that the precharge is now able to move the riser/weight upwards.

It may be like having two children, exactly balanced on a teeter-totter see-saw. Then you give one of the children an apple. Look! The other child rises all the way to the top, just because you added the weight of the apple to the first child. Did your input work of applying the lightweight apple at a moment arm of x, then raise the entire heavy weight of the child sitting at the other equal moment arm x?

http://www.youtube.com/watch?v=xi9KLLtmJKA

Even if the precharge is only offsetting a small amount of the weight of the moving parts, the input work to make the cycle is reduced. But of course in Mondrasek's model the entire weight of the moving parts is carried by the precharge, since the moving parts are actually floating at the start.
Is this the secret of the Zed's "overunity", reducing the _work input_ to obtain the same output? Well, the bollard people beat you to it.

Quote from: TinselKoala on September 24, 2012, 06:14:06 PM
Here's what  I have to say: You might not be lifting the weight at all. Your precharge is doing most of the "heavy lifting". Your added water is only adding a small amount of lift, enough to allow the precharge's "counterbalance" to raise the weight upwards.

TK,  I agree with you that the sequencing of the payload weight is an important consideration for a demonstration.  I am deep into my sim upgrade at the moment.  The program will start by automatically counterbalancing (pre-charge) the Riser, sans payload weight.  It can use one of several algorithms for doing this in order to study the advantages of each.  The Riser is set up so that it will barely sink on its own without a payload weight.  I previously did this step with an external mechanical counterweight.  Next, the payload weight is added to the riser.  Then an input force/water volume is applied until it is enough to raise the payload weight to the desired lift stroke.  Then the payload weight is removed.  Then the extra input force/ water volume is removed and the Riser is allowed to sink back to the bottom to complete the cycle.

This is the sequence I am simulating, so this is the sequence that I will ask the builders to follow and provide the measurements for as a comparison to the sim.  I believe that this will provide the truest transfer function for a single ZED.  Of course, there will be tests for different numbers of risers.

I have to apologize to everyone for being such a slow programmer and mathematician.  I am sure if I were faster at this, many of the questions would already have clear answers.

Of course, if it were easy, I would not even have to do it.  THe sim would have been written long ago by someone else.

Hello Se3d, and to all,
I am waiting for the Sim release to further discussions, just as other wait on me - I wait patiently.
Thank You Se3D for all your work, and for being able to communicate clearly with me and the others - that is a gift.

To the replication teams -
It is very hard to stay on focus with the interuptions - I understand - I appreciate your reporting of your observations - what ever they might be - I smile each time I see someone say - "not what I expected to see"
I have seen some brilliant comments here.

That is one of the points, and if you did not get your hands wet - you might not have had reason to say so.
A little refocus (again), you are continually directed to defend or deny the OU claim based on your single TBZED, that is not the challenge of the TBZED.

What I asked paraphrased - on the (1/2 ZED ) "single" ZEd Builds -   
Design your single ZED to be able to observe, measure, and record the: Base Line
Determine the Maximum head or Ideal of your design (pressure and volume in the locked down position)
Minimum pressure/volume to float with Riser weight only.
Please report the clearance between your pod and pod chamber in square inches (this will allow to see how much volume is required to precharge).
A relationship between the gap around the pod and the volume below the pod will become evident (between replication teams).
What is the maximum load (total load) you can lift the distance of .75 inch (based on the average size of the replications).
Record the pressure and volume of that stroke from the neutral base line position.
Now the preload -
add 1/3 of your total load to the riser - reset the neutral point (to just barely floating).
Record the volume and pressure - to stroke that load.
Now add the total load you lifted 3/4 of an inch and record the volume and pressure needed to stroke 3/4 of an inch.

No comparison is needed - but if you like - report anything you noticed.

This is all I need to see to direct you further, don't be distracted by the desires of others - this is a journey.

If someone wants to design a spreadsheet to organize this and post it here - I would appreciate it!

Keep up the good work.

Wayne Travis

This is some data taken from a test inspired by something similar that MileHigh had discussed in a PM.

The initial setup of the ZED has not changed since the video was posted, but more water has probably evaporated from the system by now.  The test was performed by removing the Lift Mass of 1217 mm.  In its place a container for water was placed on top of the ZED that weighed 79 grams when empty.  At this time the system was in neutral buoyancy near the top to the stroke cycle height from the previous video test.  The level of the water was marked on the fill tube for this new initial condition.
A separate container was weighed and then filled with 100 grams of water.  This water was added to the container on top of the ZED and the system was allowed to stabilize to a neutral buoyancy condition again (the table surface was tapped to facilitate the release of stiction in the ZED).  The new level of the water (rise) was marked on the fill tube for this condition.  Also, the drop in the ZED due to the added weight of the 100 grams of water was also recorded from the digital indicator.

Next, an additional 100 grams of water was weighed and added to the container on top of the ZED.  Subsequent input tube and ZED height changes were recorded.

This process of adding an additional 100 grams of water was continued until 1200 grams total was added for a total of 12 data points and the initial start condition.

Please note that this was just a test I wanted to try and is not related (I think) to the data that the Replication Teams have been asked to take.

FWIW.

M.

In case anyone really doubted it, Mondrasek's data show a linear relationship between the independent variable (the water added to the weight reservoir) and the two dependent variables (the Zed drop in response to the added weight, and the rise of the head level in the input tube in response).