larvaworld.lib.model.modules.crawler

Classes

`Crawler`	Base crawler module for peristaltic locomotion.
`StrideOscillator`	Stride-based oscillatory crawler with variable step length.
`GaussOscillator`	Gaussian-windowed oscillatory crawler.
`SquareOscillator`	Square-wave oscillatory crawler.
`PhaseOscillator`	Phase-modulated oscillatory crawler with realistic velocity profile.

Module Contents

class larvaworld.lib.model.modules.crawler.Crawler(**kwargs: Any)

Bases: larvaworld.lib.model.modules.basic.StepEffector

Base crawler module for peristaltic locomotion.

Abstract base class for crawling behavior modules that generate forward locomotion through peristaltic waves. Extends StepEffector to provide stride-based movement with oscillatory patterns.

Example:

>>> # Use concrete subclasses like StrideOscillator, GaussOscillator
>>> crawler = GaussOscillator(freq=1.5, stride_dst_mean=0.25)

class larvaworld.lib.model.modules.crawler.StrideOscillator(**kwargs: Any)

Bases: Crawler, larvaworld.lib.model.modules.basic.StepOscillator

Stride-based oscillatory crawler with variable step length.

Implements peristaltic crawling using frequency-based oscillation with stochastic stride lengths. Each stride distance is sampled from a normal distribution, providing realistic locomotion variability.

Attributes:

freq: Oscillation frequency in Hz (0.5-3.0) stride_dst_mean: Mean stride distance (fraction of body length) stride_dst_std: Stride distance standard deviation step_to_length: Current stride distance (resampled each stride)

Example:

>>> crawler = StrideOscillator(freq=1.42, stride_dst_mean=0.23, stride_dst_std=0.04)
>>> velocity = crawler.step()

freq

stride_dst_mean

stride_dst_std

step_to_length

property new_stride: float

property Act: float

act_on_complete_iteration() → None

suppresion_relief(phi_range: tuple[float, float]) → bool

class larvaworld.lib.model.modules.crawler.GaussOscillator(**kwargs: Any)

Bases: StrideOscillator

Gaussian-windowed oscillatory crawler.

Extends StrideOscillator with gaussian-shaped velocity modulation within each stride cycle. Provides smooth, biologically realistic acceleration/deceleration profiles during peristaltic crawling.

Attributes:

std: Standard deviation of gaussian window (fraction of cycle, 0-1) gauss_w: Precomputed 360-point gaussian window for cycle modulation

Example:

>>> crawler = GaussOscillator(freq=1.5, std=0.6, stride_dst_mean=0.25)
>>> velocity = crawler.step()

std

gauss_w

property Act_Phi: float

class larvaworld.lib.model.modules.crawler.SquareOscillator(**kwargs: Any)

Bases: StrideOscillator

Square-wave oscillatory crawler.

Extends StrideOscillator with square-wave velocity modulation, creating distinct power/recovery phases in each stride cycle.

Attributes:

duty: Duty cycle fraction (0-1) for square wave modulation: Controls percentage of time at maximum velocity

Example:

>>> crawler = SquareOscillator(freq=1.2, duty=0.6, stride_dst_mean=0.20)
>>> velocity = crawler.step()

duty

property Act_Phi: float

suppresion_relief(phi_range: tuple[float, float]) → bool

class larvaworld.lib.model.modules.crawler.PhaseOscillator(**kwargs: Any)

Bases: StrideOscillator

Phase-modulated oscillatory crawler with realistic velocity profile.

Extends StrideOscillator with cosine-based phase modulation, producing the most biologically realistic peristaltic crawling patterns. Velocity peaks at a configurable phase within each stride cycle.

Attributes:

max_vel_phase: Phase angle (radians) where velocity is maximum max_scaled_vel: Maximum scaled forward velocity coefficient

Example:

>>> crawler = PhaseOscillator(freq=1.42, max_vel_phase=3.49, max_scaled_vel=0.51)
>>> velocity = crawler.step()

max_vel_phase

max_scaled_vel

property Act_Phi: float

property Act_coef: float