Three-Dimensional Biomechanical Modeling for Sitting Contact Stress Analysis.

Area of Science:

• Biomechanics
• Ergonomics
• Human-Computer Interaction

Background:

• Aircraft seat design requires understanding occupant biomechanics for comfort and safety.
• Previous models often simplified analysis to 2D, limiting posture and interaction scope.

Purpose of the Study:

• To develop and validate a 3D biomechanical model of the upper body interacting with aircraft seat backrests.
• To analyze the effects of posture and recline angle on backrest loading and pressure distribution.
• To provide a tool for evaluating and optimizing aircraft seat design.

Main Methods:

• A three-dimensional biomechanical model of the upper body was developed.
• Multibody inverse kinematics and Newton-Euler dynamics were used to calculate spine segment loading.
• Contact stress theory simulated backrest pressure distribution.
• Results were validated against experimental measurements.

Main Results:

• The 3D model accurately simulated backrest loading and pressure distribution across various postures and recline angles.
• Simulation results showed good correspondence with experimental data, with a maximum average pressure error of 11.5%.
• Trunk lateral bending and backrest inclination significantly influence loading and contact conditions.

Conclusions:

• The proposed 3D biomechanical model offers a more comprehensive analysis than previous 2D models.
• The model can predict loading and pressure, aiding in aircraft backrest design evaluation and optimization.
• This approach facilitates improved comfort and safety in aircraft seating.