Assembly line positioning stage

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This article is a stub. It needs to be expanded.
Positioning stages on a conveyor chain.

Discussion of the depicted example design

The depicted example design is a cropped screen capture from the productive nanosystems video.

Present elements

Elements of the design:

  • two screws: light yellow and light blue
  • two wedges: orange and dark blue
  • slider wedge: light grey
  • adapter pallet: red
  • crystolecule under construction: mid grey at the top
  • assembly line chain segments: dark grey at the bottom

Function

It is a differential mechanism.

  • Turning the two screws in the opposite directions shifts the crystolecule upwards or downwards
  • Turning the two screws in the same direction shifts the crystolecule sideways
  • The lengthwise position is continuously swept through by the assembly lines chains movement

  • Note that this design makes heavy use of Van der Waals force. The design would not work at the macroscale

Missing elements

Adjustment screw actuation:
How the adjustment screws could be actuated is not shown. This could be done:

  • by toothed racks parallel to the assembly line that are actuated in a nontrivial reciprocate motion
  • by static cams somehow

Rotative tooltip counter stages:
Not shown in the animation is a tooltip positioning stage which would need to provide rotational degrees of freedom. Instead in the video what is shown is a simple static mill-wheel (not in the cropped screencap here) The problems with this approach is that

  • the encounter time can only be adjusted by the speed of the assembly line
  • bends and twists cannot be performed on bonds

Cain interlinks:
How the interlinking of the chain segments work is barely visible in the video. Or rather invisible. In other parts of the same video very simple non form closing hooks are shown. These seems more like a rough sketch than a concrete proposal though. To keep the animation comprehensible and to keep the modelling effort low. There are many straightforward ways to do it. A chain with pins e.g. would be a slightly bigger but natural choice.

Chain track:
There needs to be a back-pressure providing track segment below. The most trivial solution would be just a square channel. To reduce friction the middle of the square channel could be removed between the assembly stations. Ideally at places where no back-pressure is needed the chain should be running in free space. Since the assembly stations should be cramped together as close as possible there might not be much space for that. Other effects (like variations in Van der Waals force) may counteract the small gains in friction reduction. The design effort might not be justifiable. Especially at this point where we cannot physically test the designs yet but only simulate them. With gaps in the track up and down resonances might be a worry. Due to the expectable operation speeds being way below what wold results from scale natural frequencies (chosen low to keep friction levels low), this should not be a problem at all.

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