Sightline formulae in auditoria, review and new proposal to increase the visibility

Abstract

This work proposes a new formula for predicting riser’s heights in auditoria with variable risers (known as isacoustic curves). Unlike the standard formulae, the proposed one considers the effect of head shape on sightlines. The proposed formula was validated mathematically and computationally. In the mathematical validation, the results of the proposed and standard formulae, in addition to the graphical method, were compared. In the computational validation, parametric design, via Grasshopper and Anemone plugin, was utilized to simulate and calculate the Visibility Ratios VR for the proposed and standard formulae. Results showed that the proposed formula yields a more accurate and a relatively higher VR, while the standard formulae showed a “cumulative error Δ”. This error gradually becomes obvious with the distant tiers and balconies. Results also demonstrated that the enhancement in VR becomes higher in the far rows, but it is much pronounced in the hall level.

Keywords

• Auditoriums
• Sightline
• Isacoustic curve
• Computational design