The paper presents the first Bulgarian industrial robot “PROBO” build up entirely on elements, tools and human efforts at the former “Precision mechanics” laboratory within the Bulgarian Academy of Sciences. The robot was publicly demonstrated at Plovdiv exposition in 1987. The place of the robot in the world timeline is shown. A definition of “robot” is proposed, as well.
 Patarinsky, S., V. Denev, G. V. Tzvetkova. Manipulators Control System Design via Successive Simulations. Proc. of Int. Symposium on Simulation of Control Systems, IMACS, North-Holland Publishing Company, 1978, 305-309.
 Tzvetkova,G. V. Modelling of Transport Operations for Industrial Robots, Aniversary Scientific Conference 10 Years NIIR, Stara Zagora, 1987, 216-221 (in Bulgarian).