Pages Navigation Menu

Journal 3.2 System Integration and Refining Embodiments

agenda 3-2

Dizzy’s Journal Entry (Changes inspired during System Integration)

We still haven’t built anything…we haven’t even prototyped very many ideas and yet our design is evolving every day! Following a formal design process has really resulted in a lot more creativity.

I sure hope coach is right that the build process will go quickly once all the design work is done.

These are the choices that each function team presented:

  •  Mount on Trolley (plywood on turn-table)
  • Collect sticks (staggered half-cylinders…set of pincers with two on a side and one on the other)
  • Store sticks (angled deep channel)
  • Reorient sticks for AON insertion (gravity assisted servo with bike cable)
  • Reorient sticks for Nand insertion (gravity assisted servo with bike cable)
  • Reposition sticks for AON insertion (4-bar linkage)
  • Reposition sticks for Nand insertion (4-bar linkage)
  • Transfer stick from robot to holder (gravity feed with servo motor release cam)
  • Collect hangers (single finger)
  • Store hangers (robot peg)
  • Reorient Hangers (panning servo)
  • Reposition Hangers (4-bar linkage #2)
  • Transfer from robot to peg (gravity feed with servo motor release cam)

These are the re-combinations that resulted after team discussions:

  •     Mount on Trolley (rectangular 1/2 plywood mounted as diamond on trolley)
  •     Collect sticks (staggered half-cylinders…set of pincers with two on a side and one on the other)
  •     eliminated
  •     Reorient sticks for AON insertion (gravity assisted servo with bike cable)
  •     eliminated
  •     Reposition sticks for AON insertion (4-bar linkage)
  •     combine with 6
  •     eliminated
  •     Collect hangers (single finger)
  •     eliminated
  •     Reorient Hangers (panning servo)
  •     Reposition Hangers (4-bar linkage #2)
  •     eliminated

Summary of System Level Change:

  • We will now have two distinct arms on the robot instead of a rotating base.
  • Nand gates have been de-prioritized and will only be pursued if convenient to the AON arm design.
  • We will NOT store any game pieces on the robot, but instead will move them directly from their start positions to their scoring positions.

Summary of Refinements to Function 2 when integrated with other sub-systems:

Vex was charged with Function 4 (re-orient sticks for AON insertion). His gravity assisted idea has imposed changes on our gripper idea and on 4-hour’s arm design. Now:

our gripper will pivot on the arm freely in the direction that lets us tilt sticks into the AON upper holes.
the gripper will have a passive clamp that must be actively released (i.e. when the gripper is pressed against a stick, it will spread apart and rubber bands will hold the clamp-trigger closed. We will need a servo to un-latch the clamp-trigger)
the un-latching action for the clamp-trigger will also encourage the gripper to tilt (just in case gravity hasn’t done its job).

Sketches of the new Function 2 Gripper:

sketch 3-2

Important Notes:

  • our “staggered half-cylinders” is more of a half-cylinder on one side and a finger on the other.
  • Bike cable might not be stiff enough to un-latch the spring loaded lever.
  • Funnel end has been added as a “self-help” that reduces required driver precision.
  • If we don’t figure the spring loaded latch out quickly, we’ll have to go with a servo mounted to the bell (to allow the driver to lock-in a stick).

Next Step, start dimensioned drawings for the build crew to work with.

This article demonstrates how embodiment ideas may need refinement when integrated

Leave a Comment

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>