Bioinspired dynamic inclination measurement using inertial sensors

Area of Science:

• Biomechanics
• Human Physiology
• Sensor Technology

Background:

• Vestibular feedback is essential for human balance in dynamic environments.
• Understanding the body's reference equilibrium position is key to analyzing balance.
• Existing methods struggle to accurately measure orientation during motion.

Purpose of the Study:

• To propose and validate a concept of dynamic equilibrium for the human body.
• To explain body alignment on different surfaces (horizontal, inclined, accelerating).
• To develop a novel sensor system inspired by the human vestibular system.

Main Methods:

• Modeling the human body as an inverted pendulum to define a dynamic equilibrium axis.
• Designing vestibular dynamic inclinometers with multiple accelerometers and a gyroscope.
• Developing an analytical, non-time-recursive measurement algorithm to separate gravity from motion.

Main Results:

• The dynamic equilibrium axis is dependent solely on surface contact acceleration (e.g., gravity).
• The proposed sensor systems successfully measure absolute orientation and angular acceleration.
• The system effectively separates gravity from motion for ground-based moving objects.
• Experimental results validate the analytical solution for the measurement algorithm.

Conclusions:

• The dynamic equilibrium axis provides a reference for orientation measurements in dynamic conditions.
• The vestibular dynamic inclinometer offers accurate orientation sensing, inspired by biological systems.
• The analytical algorithm overcomes limitations of integration errors and body dynamics dependence.