Trampoline Stiffness Estimation by Using Robotic System for Quantitative Evaluation of Jumping Exercises.

Area of Science:

• Biomechanics
• Robotics
• Exercise Science

Background:

• Trampolines offer low-impact exercise benefits for posture, balance, and cardiopulmonary function.
• Quantifying trampoline dynamics is crucial for assessing exercise effects and ensuring user safety.
• Previous methods lacked the ability for repetitive, multi-location testing of trampoline characteristics.

Purpose of the Study:

• To develop and validate a robotic system for precise measurement of trampoline stiffness and jump dynamics.
• To quantitatively assess exercise effects by measuring elastic coefficients and vertical forces.
• To improve the accuracy of predicting trampoline performance for fitness and rehabilitation.

Main Methods:

• A robotic system with foot-shaped jigs was designed to perform automated, repetitive movements across the trampoline surface.
• Torque and position sensors guided the robot's maneuvers based on trampoline coordinates.
• Force sensors collected data on exerted forces and vertical forces (X, Y, Z coordinates).
• Linear regression based on Hooke's Law was used for model accuracy evaluation, employing MAE, RMSE, and R-squared metrics.

Main Results:

• Initial model analysis (X-distance) yielded MAE of 17.97, RMSE of 21.72, and R-squared of 0.9840.
• An expanded model including X, Y, and jig-to-jig distances improved prediction accuracy.
• The integrated model demonstrated lower MAE (15.73) and RMSE (18.82), with a higher R-squared (0.9854).

Conclusions:

• The developed robotic system accurately measures trampoline stiffness and dynamics.
• The integrated predictive model shows enhanced capability in assessing trampoline performance.
• This technology is vital for advancing safety and effectiveness in trampoline-based fitness and rehabilitation.