Single motor sequence mechanism

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Discussion Overview

The discussion revolves around creating a moving cosplay prop that mimics a specific animation sequence using a single motor mechanism. Participants explore mechanical solutions for achieving sequential movement, considering materials like cardboard, lightweight wood, and EVA foam.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • The original poster seeks a mechanical solution for sequential movement of a prop, starting from the furthest element from the motor.
  • One participant suggests a mechanism involving pinned joints and link rods that allow for rotational movement, with specific details on how the blocks would actuate sequentially.
  • Another participant expresses confidence that the suggested device will work, but notes potential noise and varying movement rates due to load on the motor.
  • A different approach is proposed using rubber bands for sequential actuation, which may simplify the design compared to the link rod mechanism.

Areas of Agreement / Disagreement

Participants present multiple competing views on how to achieve the desired movement, with no consensus on a single solution. The discussion remains unresolved regarding the best mechanical approach.

Contextual Notes

Participants express varying levels of technical understanding, and some suggestions may depend on specific design constraints or assumptions about materials and motor capabilities.

PsiQss
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Hello!
I'm currently in the process of making a moving cosplay prop, and as a perfectionist, I'd like it to move exactly like the original. Kind of like in this animation:
https://www.deviantart.com/ace-wong/art/RWBY-Qrow-s-Weapon-Animation-606779918

The problem I've stumbled upon, is how to make it sequencial and working on a single motor, so that it moves the same way back and forth. The prop will be made of cardboard, some thin lightweight wood (2mm) and EVA foam, so I think one or two motors should be able to handle it no problem.
The worst part is, the sequence is supposed to start from the element furthest away from the motor itself. I could kind of cheat it out and make small servos for each section, controlled in sequence by an arduino or something, but I think there should be a mechanical way to solve this..

I'm not too advanced in english technical terms, so for complex things, pictures or pseudo blueprints would be appreciated ^^"

Thank you in advance
 
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Try something like this, where the circles and dots represent pins to allow rotation:
P9250020.JPG

Three blocks are connected with pinned joints so they can rotate relative to each other. A series of link rods with slots actuate the blocks. The link rods are connected to each other with pins, so each link can pivot relative to the connecting links. The links have slots, and the blocks have pins inside the slots. With the link rod assembly fully to the left, all the blocks are pulled together. As the link rod assembly is pushed to the right, the rightmost block moves first. When the slot in the second link bottoms out against the pin from the second block, the second block starts to rotate. Same when the slot in the third link bottoms out against the pin from the third block. The slot in the third link is longer than the slot in the second link.
 
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The device suggested by jrmichler should work as required. It may be noise as there will be repeated impacts in the linkage, and it may move a varying rates if the increasing load significantly loads the motor.
 
Thanks a lot!
That should do the trick. Looks simple too :)
 
I couldn't view the video but here is a possibly simpler approach.
Use rubber bands instead of slotted links and rods. Vary the strength of the rubber bands if you need sequential actuation.
 
Video on Youtube
Search the term "RWBY - Qrow's Weapon Animation"