1986 Binary Arts Hexadecimal Puzzle

It consists of a sliding carriage and a stationary base.  The carriage is fitted with 8 rectangular switching bars which can pivot on their centres to angle in either of two directions.  The base, which holds the carriage during the puzzle’s operation, is fitted with an assembly containing 4 blocking keys. These keys can be present into any one of 16 positions. The object is to remove the carriage which contains the 8 switching bars.  By setting the 4 the blocking keys in various initial configurations, there are 16 puzzles to solve ranging from fairly easy (8 moves for position 1111) to extraordinarily difficult (170 moves for position 1110).