Development of two heliodon systems at MIT and recommendations for their use

Abstract

Heliodons aid the building design process by allowing the simulation of different solar angles with respect to physical scale models. At MIT, two different variations of this kind of setup are being developed. The first one consists of a small, portable heliodon that is manually operated, and meant for use outdoors with the real sun and sky. The second is a larger indoor setup that consists of a computer-controlled moving table exposed to a stationary light source. A computer interface allows the designer to automatically take different sets of model photos from a camera positioned next to or inside a model, and view the images in useful ways. Both approaches are presented in this paper and their limitations, causes of inaccuracy and potentialities are discussed based on experimental verification and through Radiance simulations. The results of a usability study with student volunteers and a case study on an existing research space on the MIT campus are also presented as a means of illustrating the potential value of such devices for building design investigation and development.