Abstract: A robot comprising a base forming an inner chamber and having an opening, a first link supported by the base and arranged for translational movement generally along a first axis relative to the base, a second link supported by the first link and arranged for rotary motion relative to the first link about a second axis generally parallel to the first axis, the second link extending from the inner chamber through the opening into an outer region, a third link supported by the second link and arranged for rotary motion relative to the second link about a third axis generally parallel to the first axis, a first actuator arranged to control the translational movement of the first link relative to the base, a second actuator arranged to control the rotary motion of the second link relative to the first link, a third actuator supported by the second link and arranged to control the rotary motion of the third link relative to the second link, and a seal between the inner chamber and the outer region arranged to isola