An object in therat environment. Objects always generate proximity signals, and may also be visible and solid. A non-solid object might be a patch on the floor as opposed to a pillar. Objects are always circular of diameter width. RatLab has no units: you can interpret time and distances how you like, as long as they are consistent. If a binary control object is specified then objects can also light up at specified times, changing their intensity by fBright according to the selected channel in the control.