+-

Greeting

Welcome to my simple forum
 
Please be considerate of all members
Cookies and Java-Script are not needed
but can be used for YOUR convenience
I do not have ads on this site so do not place any on it
I have allowed registration upon my approval
the solution is
one is 1
 

User

Welcome, Guest.
Please login or register.
 
 
 
Forgot your password?

+-Stats ezBlock

Members
Total Members: 6
Latest: milo
New This Month: 0
New This Week: 0
New Today: 0
Stats
Total Posts: 170
Total Topics: 28
Most Online Today: 2
Most Online Ever: 15
(October 26, 2019, 02:52:45 am)
Users Online
Members: 0
Guests: 1
Total: 1

Author Topic: constant velocity  (Read 353 times)

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
constant velocity
« on: July 20, 2019, 10:22:47 am »
So I do not have a self accelerating flywheel.

What I do seem to have is a constant velocity interaction.

I will label the two main parts as a drive disc and a reaction disc.  The reaction disc is free to spin while the drive disc is NOT engaged and when the drive disc IS engaged there is a constant velocity between the two discs.

The testbed at present has the drive disc held by an external component and so is not free to spin and it is on bearings to its shaft that is the same shaft that the reaction disc is on and the reaction disc is also on bearings.

The external constraint for the drive disc when the system is engaged is holding against a constant force from the drive disc, it is pulling on the constraint.  When I accelerate the reaction disc the drive disc will slow it down and when I slow down the reaction disc the drive disc will accelerate it, these actions will bring the velocity between the two discs back to there constant state and the external constraint reacts appropriately to those changing conditions.

From this I am assuming that if I were to bring the whole system up in RPM that the relative velocity between the two discs will remain at its constant rate and that the drive disc will still be applying its constant force against whatever it is connected to, aka a motor shaft that is spinning the whole system up to some RPM and as such it would be supplying that shaft with a torque which should then reduce the input from the motor.

The system as it is consumes a lot of energy in the form of work done to both create and maintain the velocity between the two discs, right now most of that energy is dissipated as heat.  In other words I am dumping electrical energy into my system (approx. 9W) and in the process of converting that energy into heat the system is creating a constant force, not that this is a heat engine, so far this appears to be a one way trip for the input electrical energy.

As time permits I will build the setup needed to mount all this on a motor and test for a drop in input while the system is engaged and see if that drop maintains itself over time.  This will be to make sure that it is not a storage and usage of momentum and is a constant.

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
Re: constant velocity
« Reply #1 on: July 24, 2019, 02:10:54 pm »
I have been taking too much time for this and not enough on the things I need to get done,,

Small scale testing has shown that I can setup the reaction disc as such that it will load the drive disc without itself taking on a rotational value, it does not show any torque of its own.
Small scale testing has also shown that I need to make it bigger so that I can produce at least enough torque to overcome frictional losses and such and demonstrate the principle.

I have had a few surprises and some funny situations while testing,, stick and slip was one that had me watching in amazement,, I actually chuckled at it :)

So what this means, by the way, is that it can create a constant difference in velocity or it can create a non acceleration of the reaction disc.

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
Re: constant velocity
« Reply #2 on: July 25, 2019, 06:40:58 am »
I up-sized part of the drive disc but without up-sizing the reaction disc.
Well now I can create a usable amount of force,, even without up-sizing the reaction disc,, while still having no rotational reaction out of the reaction disc.

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
Re: constant velocity
« Reply #3 on: July 25, 2019, 06:45:15 am »
The first thought for this setup was that I should be able to have this interaction between the drive disc and reaction disc but it was so much easier to have the RPM difference, not as effective but easy.

I think that since it is so much better I will go through the steps to make it this way,, and test to make sure there is still not some hidden interaction that I have not seen yet.

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
Re: constant velocity
« Reply #4 on: July 26, 2019, 03:27:28 pm »
I am waiting on supplies.

I used some pieces from prior testbeds and they are not overly consistent and not really what I want, they were used for many ideas and so have the very well used issues, so I had to order some stuff to build those parts,, they are not something I can print but they are not hard to "machine".

The POC (proof of principle) will not have any control systems other than the supplied power to the motor.  The system can have very good control and that would be very easy to do but for the POC I am going to keep it simple.

The system is easy to make, all in all, but without a 3D printer some parts may get to be a little tedious to make by hand.  All that would be needed is a few hand tools, a drill and a good means of measuring, I suppose you could use a "normal" printer to print the part shape on paper and then just cut it out from there.

I did run a few more tests and they looked great,, except those tests had Mr. Hand involved and so are not valid tests for sharing,, but if I can trust Mr. Hand (which I don't) then the system is good to go,, maybe that is why I ordered materials, to get Mr. Hand out of there.  :)

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
Re: constant velocity
« Reply #5 on: August 15, 2019, 11:41:47 am »
Some interesting results from another testbed I printed out,, I call this one Turtle.

I power up the system and let things come up to speed while holding the system still from rotating, I have the axle slightly tilted so gravity is holding the system down somewhat,, very weakly.  I get the system up to speed and let go and the system will rotate against the force of gravity,, very very weakly but a sustained change in position.  I reversed the input power and repeated the runs,, same thing but the rotation is in the opposite direction.

I also let it get into the rest run position and then turn off the power and wait until things  stop and let go,, and it returns to its original no power position.

webby2

  • Full Member
  • ***
  • Posts: 170
    • View Profile
Re: constant velocity
« Reply #6 on: August 15, 2019, 09:52:40 pm »
Since I am spinning things I thought that the results I was seeing might be due to windage,, so I enclosed the whole system in cardboard and ran it again,, well it seems as if it is in fact, a windage interaction, since while enclosed the reaction has gone away.

 

Powered by EzPortal