Device for Measuring Contact Reaction Forces during Animal Adhesion Landing/Takeoff from Leaf-like Compliant...

Area of Science:

• Biomechanics
• Robotics
• Evolutionary Biology

Background:

• Understanding animal locomotion on compliant substrates is crucial for biomechanics and bioinspired design.
• Measuring reaction forces on yielding surfaces like leaves presents significant challenges due to substrate compliance.
• Previous studies lacked precise measurements of forces exerted by animals on compliant materials.

Purpose of the Study:

• To introduce an innovative device for accurately quantifying reaction forces on compliant substrates during animal locomotion.
• To investigate the kinematic mechanisms and structural-functional evolution in arboreal animal locomotion.
• To provide mechanical evidence for structural-functional relationships and serve as a platform for bioinspired robotics.

Main Methods:

• Developed a device with adjustable substrate compliance using servomotors and a cantilever structure.
• Integrated force and acceleration sensors to measure interaction forces and mitigate inertial effects.
• Calibrated the device and validated its accuracy, achieving a measurement error of less than 10%.

Main Results:

• Measured force curves and calculated frictional adhesion coefficients for tree frogs and geckos.
• Adhesion force limits were found to be significantly lower (0.2–0.4 times) than previously reported values.
• The device successfully quantified interaction forces, preventing inertial force coupling effects.

Conclusions:

• The developed apparatus provides crucial mechanical data for understanding animal locomotion on compliant surfaces.
• Findings suggest lower adhesion force limits in adherent animals than previously estimated.
• This research offers a platform for advancing bioinspired robotics and understanding locomotion.