The Human Space Theory is an Architectural theory related to Human proportions and the related minimum required space; this theory was set and developed by Wissam Shekhani during his daily Architectural researches.
Wissam Shekhani designed a drawing for his Human Space Theory, describing the standard human body postures and the basic standard body movements in a specific space. The body postures are shown in a fixed spot on the ground; going in sequence of movements from the "Standing-up" posture to the "Sleeping" posture, passing through the "Sitting" posture.
His drawing showed that the basic human body sequence of movements at a fixed spot on ground had drawn a virtual curve in space. This curve will create a "Concave Conical Space (or volume)"; assuming that the "Standing-up" posture can rotate on the same fixed spot on ground, and all the basic sequence of body movements can occur in all directions.
The highest average man's height is 180 cm with closed arms and 220 cm with opened arms; that's why the virtual created "Concave Conical Space" will be chamfered from top and edges at the distance of 180 cm when the arms are closed and 220 cm when the arms are opened.
These distances are measured from the fixed spot at the ground; which is the center of the sphere (these distances are the radius of the same sphere). The sphere is chamfering the concave conical space top and edges to create the minimum space required for human basic movements (refer to Wissam's drawing)
The minimum required human space for human basic body movements will be the intersection of the following 2 spaces (or 2 volumes):
1. Space 1: The "Hemisphere" volume created by standard human heights having the fixed spot on ground as sphere center.
2. Space 2: The "Concave Conical" volume created by the sequence of human basic body movements.
Wissam's Human Space Theory had revealed the hidden Architectural and Geometric basis behind the early historical conical and hemispheric Architecture of "Tents" and "Huts" (ex: Red Indian leather tents, Nomad Fabric tents, African clay huts and Eskimo ice Igloos, etc...)