sentences:  After a series of early sculptural and kinetic works, in the early 1990s Penny created Petit Mal, which he presented internationally from 1995 to 1997 and again in 2006 after a careful restoration that maintained the original electronic configuration of the piece.Petit Mal is a human-sized robot consisting of two large wheels and a central body that appears to continuously be re-equilibrating itself.It is a robotic work of art that "attempts to explore autonomous behavior as a probe of interactivity and the research field of A-life."