Data from: Active learning design: Modeling force output for axisymmetric soft pneumatic actuators
Data files
Sep 22, 2025 version files 19.54 GB
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Mass_Testing.zip
942.43 MB
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Membrane_Characterization.zip
18.59 GB
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README.md
3.76 KB
Abstract
Soft pneumatic actuators (SPA) made from elastomeric materials can provide large strain and large force. The behavior of locally strain-restricted hyperelastic materials under inflation has been investigated thoroughly for shape reconfiguration, but requires further investigation for trajectories involving external force. In this work, we model force-pressure-height relationships for a concentrically strain-limited class of soft pneumatic actuators and demonstrate the use of this model to design SPA response for object lifting. We predict relationships under different loadings by solving energy minimization equations and verify this theory by using an automated test rig to collect rich data for n = 22 Ecoflex 00-30 membranes. We collect data using an active learning pipeline to efficiently model the design space. We show that this learned model outperforms the theory-based model and a naive regression. We use our model to optimize membrane design for different lift tasks and compare this performance to other designs. These contributions represent a step towards understanding the natural response for this class of actuator and embodying intelligent lifts in a single-pressure input actuator system.
Dataset DOI: 10.5061/dryad.jsxksn0mt
Publication DOI: 10.1109/LRA.2025.3605089
Downloading the dataset: Simply click each .zip folder (the folder, not the check box) individually to download the characterization data, test data, and ReadMe.
Description of the data and file structure
Characterization data contains folders of .csv and .mp4 data. The folders are titled with (in order): the membrane material, the membrane thickness, the membrane total radius [mm], the contact area radius [mm], the test date (year_month_day), the curing location (A/B), and the test number. Many folders contain additional values designating the dimensions of strain limiting rings [mm]: ring1 radius, ring 1 width, ring 2 radius, ring 2 width. For ring measurements, 'nan' indicates the lack of a ring. The .csv files are named with the contact height [mm] and trial number. There are associated .mp4 files in the 'videos' folder with matching names. The mass testing folder contains similar folders of .csv and .mp4 data. Folder metadata is indicated in the characterization data. File (.csv and .mp4) names indicate mass lifted [kg] and trial number. In some instances, a .pkl file is included in a test folder; this is a combination of all .csv data from that folder into a single pandas dataframe. This data was collected from parametrically designed elastomeric membranes under pneumatic inflation on custom test platforms. The data is split into two sections. Force data is obtained by a piezoelectric loadcell and HX711 breakout board, pressure via MPRLS0025, distance via VL53L0X time-of-flight sensors, flow via FS2012, and contact via limit switches or switch input.
Files and variables
File: Membrane_Characterization.zip
Description:
- The .csv files contain (in order): time [ms], force [lbf], pressure [PSI], distance1 [mm], distance2 [mm], volumetric pneumatic flow [mL/s], and contact [binary].
- The .csv filenames contain (in order): contact height [mm], trial number.
- The folder names contain (in order): membrane material [Ecoflex or Dragonskin], thickness [mm], outer radius [mm], contact radius [mm], test date [yr month day], curing station [A/B], test number, and (sometimes) ring data [radius1, width1, radius2, width2].
- Distance 1 is on the left side of the test rig, while distance 2 is on the right side. These are the raw distances from the sensor and need to be altered to calculate the distance from the membrane. A distance measurement of 999 indicates an error.
- Contact indicates if the membrane is encroaching on the test setup; 0 is positive contact.
- Pressure data is measured inside the pressure chamber and should be precise during inflation and deflation.
File: Mass_Testing.zip
Description:
- The .csv files contain (in order): time [ms], pressure [PSI], distance [mm], contact [binary].
- The .csv filenames contain (in order): mass [kg], trial number.
- The folder names contain (in order): membrane material [Ecoflex or Dragonskin], thickness [mm], outer radius [mm], contact radius [mm], test date [yr month day], curing station [A/B], test number, and ring data [radius1, width1, radius2, width2].
- Contact indicates a user input and begins deflation; 0 is a positive user input.
- Pressure data is measured upstream from the membrane during inflation and downstream from the membrane during deflation. Deflation pressure is considered more reliable as deflation occurs more slowly.
Code/software
.csv files and .mp4 files should be viewable in any text editor and video viewer, respectively.