The Spreadsheet Anthropometric Scaling System, SASS, allows flexible interactive access to all anthropometric variables needed to define a computer-based human figure [13][14][24][23]. SASS works as a relational spreadsheet supporting both body segment, joint, and attribute information. Segment dimensions and center of mass, joint degrees of freedom and movement limits, and joint strength data are supported. It connects related body dimensions and parameters, such as relevant segment lengths to stature, or segment mass to scale. Besides statistical data, SASS provides access to an anthropometric database containing data from ``real-world'' individuals.
SASS supplies the dimensions of each segment needed to define a virtual human figure, based upon population data supplied as input. The human model generated by SASS consists of 68 segments (body structures), of which 67 have a geometrical representation. For each of these segments, there are 3 dimensions required, namely, length, width, and thickness. The articulation of the human model consists of 66 joints, (1 to 3 degrees of freedom per joint) for a total of 138 degrees of freedom. The program supplies the corresponding joint limits. Hands are included.
Francisco Azuola will be enhancing SASS to support the specification of body sizes via direct anthropometric measurements (sam's), as well as joint center to center segment x-y-z measurements [1]. Supporting a set of direct body measurements will make it easier for designers to use SASS. It also is a more intuitive and natural way to specify body dimensions, and users seem to agree that this is an option that could make SASS more friendly.
Ann Song and Susanna Wei are building X-SASS: SASS running under the X-window programming environment [31]. Porting SASS to X by using Tk makes it easier to maintain the code and extend applications. Picture-buttons make a user-friendly interface, and pull-down menus increase usability, power, and flexibility. Multiple figures may also be simultaneously changed and re-scaled.