Operating at speeds of more than 300°/s and offering position control with 0.012857° resolution, the PTU-D46 computer-controlled pan-tilt units from Directed Perception Inc. are suitable for video surveillance, tracking, directional antenna and laser motion control, and mobile robotics. The devices provide on-the-fly speed and position changes to enable position and velocity servo control, and a payload capacity of up to 9 lb. They feature a 5.2 X 3.6-in. footprint, plug-and-play control via an RS-232 terminal and built-in RS-485 multidrop network capabilities. The units are available with an optional C-language application programming interface or a LabView driver.