SAE J941_200810

This SAE Recommended Practice establishes the location of drivers’ eyes inside a vehicle. Elliptical (eyellipse) models in three dimensions are used to represent tangent cutoff percentiles of driver eye locations. Procedures are provided to construct 95th and 99th percentile tangent cutoff eyellipses for a 50/50 gender mix, adult user population. Neck pivot (P) points are defined in Section 6 to establish specific left and right eye points for direct and indirect viewing tasks described in SAE J1050. These P points are defined only for the adjustable seat eyellipses defined in Section 4. This document applies to Class A Vehicles (Passenger Cars, Multipurpose Passenger Vehicles, and Light Trucks) as defined in SAE J1100. It also applies to Class B vehicles (Heavy Trucks), although these eyellipses have not been updated from previous versions of SAE J941. The appendices are provided for information only and are not a requirement of this document. In the January 2008 revision of this document, fixed seat eyellipses and their locating equations were modified based on new data for second row passenger eye locations presented by UMTRI. In general the new centroid is lower by about 20 mm and forward by 10 mm compared to SAE J941:2002. The new equations also resulted in small changes to the length of the ellipse X and Z axes. Other changes included: – providing a procedure in Appendix B for locating an eyellipse in a second row seat that has adjustable seat track travel or adjustable back angle – extending the applicability of Appendix A from a driver population having 25% females to one having only 10% females – determining the X location of the eyellipse centroid based on a ball of foot reference point (BOFRP) rather than PRP – editorial clarifications In this revision the reference point for locating the Z coordinate of the eyellipse centroid, for driver seats that provide vertical adjustment, was changed from the middle of the vertical adjustment range to 20 mm above the full down H-point travel path. This change applies to seats having a vertical adjustment range that exceeds 40 mm.