Beetle Navigation

1 collaborator

Jake Hofgard (Author)

WHAT IS IT?

This model demonstrates the navigation techniques of a dung beetle. The beetle reorients itself at the observer's discretion and attempts to reach the other edge of the grid while navigating around obstacles.

HOW IT WORKS

The beetle first must move a certain number of steps, choosing a random angle each time for its next step. After this number of steps, which is set by the observer, the beetle reorients for a certain number of ticks before resetting its orientation and moving the same number of steps at a random angle once again. If the beetle encounters an obstacle, it moves around it by comparing the y-coordinate of the obstacle to its own in order to go either up or down.

HOW TO USE IT

SETUP: Sets up one beetle, one ball of dung, and the background.

GO: Runs the simulation.

STEP-ANGLE: The set of values from which the beetle can choose its random angle of navigation.

NUMBER-STEPS: The number of steps before the beetle reorients itself.

REORIENT-TIMER: The amount of time the beetle spends reorienting.

SHOW-PEN: Traces/does not trace the path of the beetle.

NUMBER-OBSTACLES: Sets the number of obstacles.

SIZE-OBSTACLES: Sets the size of obstacles.

THINGS TO NOTICE

View the Distance vs. Time graph which demonstrates the beetle's distance from its starting point to its current point as time progresses. Notice how changing the step angle and number of steps in between orientations alters this graph. The beetle changes color from black to gray when reorienting to indicate that it is reorienting. Also observe the method by which the beetle navigates around obstacles.

THINGS TO TRY

Change the step angle or number of steps to simulate a rough surface of navigation for the beetle, the amount of time the beetle spends reorienting, or the number and size of obstacles in order to observe changes in the beetle's navigation patterns.

Comments and Questions

Click to Run Model

breed [ boxes box ]

breed [ beetles beetle ]

beetles-own [
  beetle-home
  distance-home
  moving-timer
  time-reorienting
  x-position
  y-position
]

to setup
  clear-all
  ask patches [ set pcolor green + (random-float 0.8) - 0.4 ]
  setup-beetle
  setup-obstacles
  reset-ticks
end 

to setup-beetle
  create-beetles 1 [
    set shape "bug"
    set color black
    set size 3.5
  ]
  ask beetles [
    setxy -24 0
    facexy 25 0
    set moving-timer number-steps
    set time-reorienting reorient-timer
    set beetle-home patch-here
    ifelse show-pen?
      [ pen-down ]
      [ pen-up ]
  ]
end 

to setup-obstacles
  ask n-of number-obstacles patches with [
    distancexy -25 0 > 4 and abs pxcor < (max-pxcor - 5) and
    abs pycor < (max-pycor - 5)
  ] [
    sprout-boxes 1 [
      set shape "circle"
      set size size-obstacles
      set color 1.5
    ]
  ]
end 

to go
  if all? beetles [ xcor >= 24 ]
  [ stop ]
  ask beetles [
  ifelse moving-timer >= 1
    [ move-beetles ]
    [ reorient ]
  ]
  tick
end 

to move-beetles
  ask beetles [
    set heading random-float step-angle + 90
    fd 1
    set distance-home distance beetle-home
    set moving-timer moving-timer - 1
    if count boxes in-cone (size-obstacles) 180 > 0
    [ go-another-direction ]
    if abs pxcor >= 25 or abs pycor >= 24
    [ set heading random 360
      bk 1 ]
  ]
end 

to go-another-direction
  ask beetles [
    let target one-of boxes in-radius size-obstacles
    set x-position [ xcor ] of target
    set y-position [ ycor ] of target
    ifelse step-angle < 90 [
      ifelse y-position > ycor
      [ lt random 45
        bk 1
        lt random 90
        bk 1 ]
      [ rt random 45
        bk 1
        rt random 90
        bk 1 ]
    ]
    [
      if x-position < xcor and y-position < ycor
      [ case-one ]
      if x-position > xcor and y-position > ycor
      [ case-one ]
      if x-position > xcor and y-position < ycor
      [ case-two ]
      if x-position < xcor and y-position > ycor
      [ case-two ]
    ]
  ]
end 

to case-one
  ask beetles [
    bk 1
    rt random 15
    bk 1
]
end 

to case-two
  ask beetles [
    bk 1
    lt random 15
    bk 1
]
end 

to reorient
  ask beetles [
    set shape "rotating bug"
    set color 3
    set heading heading + ( 1 / reorient-timer ) * 360
    set time-reorienting time-reorienting - 1
    if time-reorienting < 1 [
      set heading 90
      set shape "bug"
      set color black
      set moving-timer number-steps
      set time-reorienting reorient-timer
    ]
  ]
end

There are 9 versions of this model.

Uploaded by	When	Description	Download
Jake Hofgard	about 7 years ago	Changes default speed	Download this version
Jake Hofgard	about 7 years ago	Updated Info	Download this version
Jake Hofgard	about 7 years ago	Information added	Download this version
Jake Hofgard	about 7 years ago	Obstacle navigation corrected	Download this version
Jake Hofgard	about 7 years ago	Syntax Error Corrected	Download this version
Jake Hofgard	about 7 years ago	Deleted unnecessary code	Download this version
Jake Hofgard	about 7 years ago	Obstacle navigation partially fixed	Download this version
Jake Hofgard	about 7 years ago	Setup button fixed	Download this version
Jake Hofgard	about 7 years ago	Initial upload	Download this version

Attached files

File	Type	Description	Last updated
Beetle Navigation.png	preview	Preview for 'Beetle Navigation'	about 7 years ago, by Jake Hofgard	Download

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