The Surveyor 5000 was produced in 2008, and has two key features.  The first is a modified wheelchair serving as the mobility base.  This differential drive base uses two powerful 24-volt motors, two motorcycle batteries, and can travel 5 MPH for 8 hours.  The base even includes encoders, giving the robot information on how fast it is driving or turning.  The other key feature is the custom-built steel rack:  this rack provides mounting space for two contained CPUs running Windows or Linux (dual-boot), a motor controller, a wireless access point, and a pan-tilt-zoom camera, along with plenty of additional space for user-added equipment.  Standing at about 4’6” tall with a carrying capacity of 200-300 pounds, this robot is truly a workhorse.