Difference between revisions of "Branching factor"

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(Related: added link to yet unwritten page * Convergent assembly depth)
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Branching factor is a characteristic number for [[convergent assembly]]. <br>
 
Branching factor is a characteristic number for [[convergent assembly]]. <br>
Let's abbreviate it with b here.
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Let's abbreviate it with b here. <small>(Otherwhere also used: n, B, ...)</small>
  
 
In a first approximation of [[convergent assembly]] organized into [[assembly layers]] <br>
 
In a first approximation of [[convergent assembly]] organized into [[assembly layers]] <br>
 
each assembly chamber has exactly b<sup>2</sup> sub-chambers. <br>
 
each assembly chamber has exactly b<sup>2</sup> sub-chambers. <br>
These sun-chambers collectively prepare:
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These sub-chambers collectively prepare:
 
* b<sup>3</sup> sub-parts in once full cycles time or equivalently
 
* b<sup>3</sup> sub-parts in once full cycles time or equivalently
 
* b<sup>2</sup> sub-parts in b<sup>-1</sup> = 1/b of a full cycles time  
 
* b<sup>2</sup> sub-parts in b<sup>-1</sup> = 1/b of a full cycles time  
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== Related ==
 
== Related ==
  
* [[Convergent assembly]]
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* [[Gem-gum factory design parameters]]
* [[Chamber to part size ratio]]
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* '''[[Convergent assembly]]'''
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* '''[[Math of convergent assembly]]'''
 
* [[Convergent assembly depth]]
 
* [[Convergent assembly depth]]
 
* [[Error handling]]
 
* [[Error handling]]
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* [[Level throughput balancing]]
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* [[Higher throughput of smaller machinery]]
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* '''[[Limits to lower friction despite higher bearing area]]'''
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* [[Assembly layer]]
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----
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* [[Chamber to part size ratio]] ... another important factor

Latest revision as of 10:29, 11 February 2024

This article is a stub. It needs to be expanded.

Branching factor is a characteristic number for convergent assembly.
Let's abbreviate it with b here. (Otherwhere also used: n, B, ...)

In a first approximation of convergent assembly organized into assembly layers
each assembly chamber has exactly b2 sub-chambers.
These sub-chambers collectively prepare:

  • b3 sub-parts in once full cycles time or equivalently
  • b2 sub-parts in b-1 = 1/b of a full cycles time

Concrete visual example:
A chamber making 27 piece Rubiks cube like assemblies
has only 9 chambers in the next smaller sub-layer
but this sub-layer works with the 3-fold frequency,
so the throughput of the sub-layer matches with the throughput of the chamber atop.
("sub-layer" above refers to just the local patch of the sub-layer below one single chamber atop)

Pros and cons of higher branching factors

Benefits of higher branching factors are:

  • More design freedom in parts – less constrained by the production process
  • A bigger (better) assembly-motion-distance to transport-motion-distance ratio – in case there are slower operating stacked layers of same size

Downside of higher branching factors:
Given constant speed bigger branching factors lead to longer assembly times.
Doubled branching factor gives one eighth of the throughput.
It's a third power scaling law.

Misc notes

The branching factor can vary over a stack of layers.
When and how much to do that depends on the details of a concrete implementation.

Not factored in in a a first approximation of convergent assembly are eventual errors.
Since this is not compensated in space it needs to be compensated in time. That is: delays.

Related