Two-dimensional drafting template and three-dimensional computer model representing the average adult male in automotive seated postures

A growing interest for automobile customers is the comfort of the seats in their cars. The automotive seats should fit the body shapes of people and move the way people move in seated postures.

This thesis describes the development of a template (JOHN 2-D) that represents the skeletal framework of the human body for the average adult male in seated postures. JOHN 2-D represents the body with a skull, thorax, pelvis and a gear system to represent the cervical and lumbar segments of the spine. JOHN 2-D moves the thorax relative to the pelvis with lumbar articulation and moves the skull relative to the thorax with cervical spine articulation.

The torso of the average adult male was investigated to develop a representative outer body surface of the back of an occupant in an automobile seat. This outer body surface was created on a three-dimensional computer model (JOHN 3-D) of the human skeleton. The vertebral column and back muscles were added to the skeleton and then a skin layer was created over the back surface of the model. A motion program was developed to locate JOHN 3-D in different body postures. Then a skin was created for the model in these postures.

It was concluded that the work presented in this thesis can be used to compare existing automotive seat designs with human body postures and develop new seat designs to better fit the average adult male body.