Figure 4.
Surface models fitted into top lid of the prototype shown in Figure 1. Model A, B, and C in (a–c), respectively.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.