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.
Cargo transport by 2 plus (blue) and 2 minus (yellow) motors: possible configurations (0), (+), and (−) of motors bound to the MT. For configuration (0), the motors block each other so that the cargo does not move. For configuration (+) and (−), the cargo exhibits fast plus and minus motion, respectively.
