Data from: Stability and agility trade-offs in spring-wing systems
Data files
Nov 25, 2024 version files 31.19 MB
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ExportForBB_updated_v3.zip
31.19 MB
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README.md
2.57 KB
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Table_weis_fogh_numbers_and_insect_wings.csv
1.78 KB
Abstract
Flying insects are thought to achieve energy-efficient flapping flight by storing and releasing elastic energy in their muscles, tendons, and thorax. However, "spring-wing" flight systems consisting of elastic elements coupled to nonlinear, unsteady aerodynamic forces also present possible challenges to generating stable and responsive wing motions. The energetic efficiency from resonance in insect flight is measured by the Weis-Fogh number (N), which is the ratio of peak inertial force to aerodynamic force. In this paper, we present experiments and modeling to study how resonance efficiency (which increases with N) influences the control responsiveness and perturbation resistance of flapping wingbeats. In our first experiments, we provide a step change in the input forcing amplitude to a series-elastic spring-wing system and observe the response time of the wing amplitude increase. In our second experiments, we provide an external fluid flow directed at the flapping wing and study the perturbed steady-state wing motion. We evaluate both experiments across Weis-Fogh numbers from 1 < N < 10. The results indicate that spring-wing systems designed for maximum energetic efficiency also experience trade-offs in agility and stability as the Weis-Fogh number increases. Our results demonstrate that energetic efficiency and wing maneuverability are in conflict in resonant spring-wing systems suggesting that mechanical resonance presents tradeoffs in insect flight control and stability.
https://doi.org/10.5061/dryad.34tmpg4tw
Robotic Spring-Wing Experiment Data
Description of Data and File Structure
Data is organized into two folders corresponding to the two main experiments presented in the manuscript
- riseStep, containing the data from the responsiveness experiments
- perturbed, containing the data from the constant flow experiments
Responsiveness Data (riseStep)
Data is stored in .mat files using the naming format
N[TestNumber]_riseStep_[RepNumber] ([Date]).mat
Each .mat file contains
- ampReference: a Simulink Parameter containing the target motor amplitude in degrees
- fr: the frequency (in Hz) at which the system is driven
- runtime: the total time (in seconds) that the experiment is run
- ScopeData: A struct object containing the collected experiment data.
ScopeData contains the elapsed experiment time (seconds, 1 kHz sampling frequency), and a signals struct that contains
four (4) data elements
- rawAngles: n-by-2 array, first column is the angle of the motor, second is the angle of the wing (degrees).
- wingAmpDeg: Real-time estimate of wing angle. Used only for tracking (degrees).
- motAmpDeg: Real-time estimate of motor angle. Used only for tracking (degrees).
- analogVoltage: 0-5V command to stepper motor controller that drives wing flapping (Volts).
Constant Flow Data (perturbed)
Data has the same structure as in the riseStep folder, with the naming format
N[TestNumber]_perturbed_[Orientation]_1 ([Date]).mat
The orientation refers to the angle the wing makes with the jet of water. “Neutral” is perpendicular to the jet,
“minus” is towards the jet, and “plus” is away from the jet. Only the “neutral” and “unperturbed” data is used
in the manuscript.
The image files in the folder show the wing angle data from all four orientations for each test, normalized to the
unperturbed wing amplitude. The images labeled “_var” show just one period of angle data.
Table_weis_fogh_numbers_and_insect_wings.csv
This is a csv file with the calculated Weis-Fogh numbers reported in the literature. Columns are organized by Insect group, species, Weis-Fogh number, animal mass, and the reference source.
Code/Software
All data was collected, analyzed and plotted using Simulink Desktop Real-Time and MATLAB (Mathworks). Data files
may be accessed using MATLAB or Octave.