+-

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: 7
Latest: txesajim
New This Month: 0
New This Week: 0
New Today: 0
Stats
Total Posts: 445
Total Topics: 50
Most Online Today: 31
Most Online Ever: 309
(March 14, 2020, 03:55:59 pm)
Users Online
Members: 0
Guests: 14
Total: 14

Author Topic: Picking things back up  (Read 32171 times)

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Picking things back up
« on: April 04, 2020, 06:02:10 am »
It has been about a year since I had to stop playing with my stuff and I am finally getting back to playing with things.

What I was trying to do is simple,, I have been trying to pass an input into a flywheel that is mounted on the end of an arm that is free to move.  This input is from a source that is mounted on the very arm that the flywheel is mounted to and the goal is for me to spin up the flywheel without imparting a rotation into the arm as well.

Some of my prior printed test-bed parts made the move but not all of them,, some tests I need to redo since it has been so long since I did them,, and all that kind of stuff that happens when time passes.

I am not in any kind of hurry so I will take my time and post things when I feel like it :)

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #1 on: April 07, 2020, 12:18:36 pm »
with what I have, as far as parts go and a few that I printed out I have started running a few basic tests just to bring myself back up to speed with where I was.

I purposely built this setup a little loose, that is it was supposed deflect a little bit to provide for a visual indicator of where the forces are heading and stuff,, well it does not flex so much,, so much for that idea :)


webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #2 on: April 29, 2020, 07:35:54 pm »
Fun stuff so far,, but nothing that I can say is conclusive.

Using spring force gauges for things that are not constant does not make for very good measurements, they are more of an indicator without giving exact numbers.

The indications then are that I can indeed accelerate a flywheel mass without the associated forces imparted into the arm that is holding it , what I mean by indicates,, well the force meters appear to show the same change in forces and in the directions I thought that they should,, but appearing to show and what they actually are are two different things.

I am building another test-bed,, this one is smaller :)  I find that funny since almost everyone wants to go bigger because bigger will show it better!!!  I am also trying to make it so I can use the same input direction and spin the flywheel in either direction,, a choice by design then can be made as to which way the flywheel spins.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #3 on: May 01, 2020, 07:13:00 pm »
Not sure which one to post this to,,

I have my printer printing some small gears,, I never was able to go below a 0.75 module before, but with this printer I am down at 0.5M,, it is kind of nice.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #4 on: May 07, 2020, 07:07:46 pm »
I had the basic mini system all put together and tried using the mini motor to run it,, unfortunately the mini motor is not strong enough to overcome the losses due to my printed gears,, I will try and find some others that will work,, the motors may have to grow a little bit but I am still going to try and keep it pretty small.

I could get it to spin up if I used 2 mini motors tagged in-line and wired in parallel but that is not going to work for me as a solution.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #5 on: June 07, 2020, 06:44:16 am »
I have 2 builds that I am working with right now, I have the mini-build and I have my "other build".

The other build is kind of modular, that is I have made it so that I can take it apart and re-assemble it in a few different configurations which is nice in that it only takes me a few minutes to take it apart and put it back together again.  I had to make a compromise with this build, not wanting to spend the money for some parts to do it better until I could see if it would be worth the expense.  I have been playing with it while waiting for parts to show up for the mini-build and it has been interesting and it appears like I can use it to end up with a flywheel mass on an arm being accelerated without a net influence to the arm,, but due to the compromise I made I can not say for sure but what I see is enough to warrant spending the money,, more wait time for those parts to show up.

The mini-build is getting close, I have this pesky gear to get printed and then I move on with the other parts.  I am not building this one with all of the controls in place, that is above my pay grade, but I am going to try and just balance forces the best I can.  It will work in a sort of DC offset AC pattern kind of way with a small hint of my simple mechanical rectifier at work.  My first test-bed for this one showed a lot of promise but the compromise I made for that one precludes it from showing anything absolute except that the forces are in the general place and direction I thought they would be,, just not able to rule out any other forces that I have not thought of or seen.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #6 on: June 14, 2020, 07:50:45 am »
Interesting but most likely not useful,,

My other build is very modular, meaning that I can easily take it apart and then re-assemble with the parts in a different configuration so that I can change the path all the forces take to get to the same end point.

I have it together in one orientation and did not have any external mechanical connections made and was checking on the internal added force stuff,, well I fired up the internal added force and the system started to do its thing and then I noticed that being free to spin about its axle the whole system started to rotate and the mass of the system was also rotating and it was rotating in the direction of rotation of the whole system.  The rotation of the whole system seems to settled down at the same rate of the internal rotation.

I reversed the polarity of the internal source and the rotation also reversed.  It takes a little bit of time for the whole thing to stabilize but once it gets itself organized it settles down quickly to the stable RPM.

I think it is interesting reaction.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #7 on: June 25, 2020, 06:51:56 am »
my modular build is not as modular as I would like,, normal stuff there,, but while I was working out some other parts I would like I think I ran across an interesting situation.

I think I have a twofer,, for those that do not understand that word it is short for " two for one".

It is elctro-mechanical in design and I made a few parts to put a quick test-bed together to see if what I thought could be there is there, in some form or another.  That crude play time seemed to support what I think I can do so I am now making and designing some parts to do a comparison test since the electrical stuff I am using is not very efficient I can only compare these significantly less than 50% efficient devices input costs against the same load without my system and going through my system.

I am doomed to fail of-course,, but it is fun and exciting anyway.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #8 on: June 25, 2020, 06:59:01 am »
I am using motors like these, as an fyi,,

https://www.amazon.com/Cylewet-Motor-Shaft-Arduino-CYT1037/dp/B01N9MS3UZ

They suck as far as efficiency goes :)  They do work great for building motorized toys,, a few cars and tanks and well I had them lying around so I used them.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #9 on: July 07, 2020, 07:53:38 am »
While I am contemplating the next step and changes to twofer I am working on 2 other test-beds that I am using to try and look closer at some of the relationships I am using in twofer.

I am planning on changing the drive system for twofer, I am going to move it external of the system to make it easier.
I also need to balance the system, this seems to have a very large impact on the draw of the input motor.

I am NOT planning on actually pulling twofer completely apart, but instead will try and use add-on parts only,, keeping the first test-bed intact could be a good thing.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #10 on: July 10, 2020, 11:26:21 am »
So I am actually working on 3 test-beds as well as re-doing a bunch of parts for twofer,,

I only have 1 slow printer,, but I am not is a big hurry.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #11 on: July 11, 2020, 05:49:36 am »
Strange thought.

If this system is working the way I think it is then there might be a way to utilize the system to provide for a force that can oppose gravity.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #12 on: July 20, 2020, 04:39:06 am »
Back to redesigning things again.

What I think I am playing with is a torque limited device, that is to say that so long as I can supply a torque that is greater than the resistance the system will accelerate regardless of how fast the source of torque is rotating.

I am designing and printing out new parts with what I think is a reasonable setup to get there.  With one test-bed I ran into a lot of air resistance, which is a torque to overcome, that limited the RPM of the system.  I am going to run into that condition with any test-bed but if I know what that cost of rotation is then I can supply enough input to overcome that and the system should then keep accelerating.  I know that this sounds just like a normal motor but in this case the RPM of the motor should not change I would just need to have the motor pass more current at the same RPM which is accomplished by providing a higher voltage to the motor, again sounds familiar but the RPM of the motor should not change.

This is what I am going to be building for and testing for.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #13 on: July 27, 2020, 07:02:59 pm »
still working on it but one test run I have made spins up faster than it should, at a cost of torque, but it is still limited in the amount of RPM it reaches.

webby2

  • Sr. Member
  • ****
  • Posts: 435
    • View Profile
Re: Picking things back up
« Reply #14 on: July 28, 2020, 07:03:40 am »
Funny thing,,  When you apply a force between 2 non equal masses usually the larger mass does not move as much as the smaller mass, in this case the larger mass is trying to do all the moving :)

Not sure what that means, it could be a frictional loss thing or maybe something else.

 

Powered by EzPortal