Self energized pendulum...

[iacob alex]

.....if you take a look at the real world physics exercised by the young generation:
     https://www.real-world-physics-problems.com/physics-of-skateboarding.html
     https://nickdrachman.wordpress.com/2020/03/26/the-physics-of-vert-skating/
     The performer is pumping on a half-pipe to increase his vertical take-off ( due to a greater velocity...), when he exit the pipe ( half circle ).
     He is doing work and transfer of energy is being added to the system...the performer ( equivalent to a mass-spring/elastic inverted pendulum ) acts as a common energized pendulum.
     If we "copy" his motion with a simple arrangement:
     -pivot/fulcrum
     -tube (!with two springs and a free sliding mass ,inside )
.....can we test the concept of SELF ROTATING ( energized ) elastic (spring ) PENDULUM !?
      Al_ex

[iacob alex]

.....is a starting concept to play an elastic body as a mass-spring pendulum.
If you take a look at a lot of theory : https://youtu.be/_qnRudiEfwI
.....then to a short "pragmatic" movie : https://youtu.be/dkPX8Ce0jIk
.....we really have some beginning images to think about.
     Now , let's replace the performer ( elastic body ) with a mass-spring system , if we intend to make a "copy" of this sport/game as a rotating elastic/spring pendulum (equivalent to a half-pipe skating/pumping...)...but with a repetitive starting point...?!
     Take a look at : https://youtu.be/GlhGh5bgXmg
      If we replace the rods with a single tube (supported in the middle/pivot ), then we introduce the small rod as a free sliding mass in , and add two springs inside...have we a "new game" related to gravity and inertia ?!
      A spring (any of them) "mimics" performer's  "crouch " and "hands up"  as an "elementary robot".
      The inside free sliding mass/rod can slip in a momentarily / short time on an inclined track/tube...so to attain again the  starting point and make a contact with the second spring ?!
      For me the "spring-sliding mass-spring" is a factual expression of the atomic (a-tomos) concept face to phenomena (gravity and inertia).
      By all means , a simple test can be more conclusive about a possible "loop the loop " and why not?..a hopeful "self" motion !?
       Al_ex

[iacob alex]

.....as an introductory text , at :
https://overunity.com/18685/walking-around-a-fulcrum/msg552671/#msg552671
     Al_ex

[iacob alex]

.....with 2*g , at the bottom of his swing , if we drop a simple pendulum from the horizontal position :
     https://physics.unm.edu/pandaweb/demos/questions/predictive1/index.html
.....with an acceleration >2*g , at the bottom of his swing , if we drop a simple pendulum from the vertical position/inverted pendulum , but in any test ...it never makes a full (360 *) turn.
     Regarding an elastic / spring pendulum , if we drop it from the horizontal position have we something alike the half-pipe performer's "higher and speeding up " feat ?
     Even more...if we drop an elastic/spring pendulum from the vertical position/inverted elastic pendulum in a simple test...it...a full(360*) turn ?!
     Al_ex

[kolbacict]

By all means , a simple test can be more conclusive about a possible "loop the loop " and why not?..a hopeful "self" motion !?

Milcovich's two-stage pendulum ,somebody was achieve selfrunning ?

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Oberth effect
But what if we discard part of the mass of the pendulum at its lowest point, when its velocity and kinetic energy are maximum?