Serial Attached SCSI speeds up to 12 Gbit/s. The physical SAS connector comes in several different variants: "Nearline SAS" (abbreviated to "NL-SAS", and sometimes called "midline SAS") drives have a SAS interface, but head, media, and rotational speed of traditional enterprise-class SATA drives, so they cost less than other SAS drives. When compared to SATA, NL-SAS drives have the following benefits: Serial Attached SCSI In computing, Serial Attached SCSI (SAS) is a point-to-point serial protocol that moves data to and from computer-storage devices such as hard drives and tape drives. SAS replaces the older Parallel SCSI (Parallel Small Computer System Interface, usually pronounced
Parallel manipulator mechanisms for the movement of either the robot on its base, or one or more manipulator arms. Their 'parallel' distinction, as opposed to a serial manipulator, is that the end effector (or 'hand') of this linkage (or 'arm') is directly connected to its base by a number of (usually three or six) separate and independent linkages working simultaneously. No geometrical parallelism is implied. A parallel manipulator is designed so that each chain is usually short, simple and can thus be rigid against unwanted movement, compared to a serial manipulator. Errors in one chain's positioning are averaged in conjunction with the