Introduction to Adevs continuous modeling

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Introduction to Adevs continuous modeling
Lee, Hojun
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Contents

• Adevs classes for continuous modeling
• An Example cherry bomb
• Another example for practice
• Ref. Adevs manual http//www.ornl.gov/1qn/adevs/
  adevs-docs/manual.pdf

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Adevs classes for continuous modeling

• Basic adevs_dess.h
• discrete_output_func()
• discrtet_action_func()
• evolve_func()
• next_event_func()
• state_changed()
• Modified adevs_rk4.h/ adevs_rk45.h
• der_func()
• state_event_func()
• time_event_func()
• discrete_action()
• discrete_output()
• state_changed()

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An Example Cherry Bomb(1/2)

• A cherry bomb is dropped from a height of 1 meter
  and bounces until it explodes or is doused with
  water
• Move only up and down and perfectly elastic.
• Explode in 2 seconds after it is lit.
• Dousing is an input event which gets the fuse
  off, boom message comes out as an output when
  it explodes.

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An Example Cherry Bomb(2/2)

• Continuous state variables height(h),
  velocity(v), time(t)
• Discrete state variable phase(lit, douse,
  explode)
• Differential equations
• dv/dt -9.8 m/s
• dh/dt v
• Condition
• If (h0 v lt0) then v -v

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Another example for practice(1/2)

• Track generator (2D cartesian coordinate)
• A target moves in the x direction starting from
  (0, 0) at velocity of 100m/s
• From 1 sec to 1.5 sec it turns left by 10 degree
• No input, No output

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Another example for practice(2/2)

• Continuous state variables x , y, angle(theta),
  time(t)
• Discrete state variable phase (start, stop)
• Differential Equ.
• dx/dt velocitycos(theta)
• dy/dt velocitysin(theta)
• Condition
• If (t gt1.0t lt1.5) then theta 10 degree
• else theta 0

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Thank you

• Questions?