If you're worried about robots taking over the world, relax. The robot revolution is hardly imminent, and even when it gets here, say the experts, you will not be rendered obsolete.

The Robot Institute of America estimates that there are fewer than 5,000 robots now in the United States. Japan is believed to have about 14,000, but some are so primitive that experts here regard them as merely "industrial machines."

Although industrial robots are still very expensive (about $135,000), futurist Marvin Cetron of Forecasting International Ltd., Arlington, predicts that by 1990 they will cost about as much as a new car. Cetron, coauthor with Washington Post staff writer Thomas O'Toole of Encounters With the Future (McGraw-Hill, $12.95), believes that robots will be used in industry long before they become fixtures in the home.

According to Cetron and robotics expert James S. Albus of the National Bureau of Standards, robots first will be used for work that is dangerous or extremely simple and repetitive. Albus envisions their widest use in construction, underwater mining and farming, space manufacturing, planetary exploration and factory work such as inventory, tool management, machining, assembly, finishing and inspection.

Robots, he says, "could mine coal without getting black lung disease, mine gold without being tempted to steal it and do such work as cleaning out the Three Mile Island nuclear reactor."

But the doomsayers' fears that robots will cause massive unemployment by displacing human workers are overstated, claim Andrus, Cetron and others in the field. Although robots are very good and fast at performing repetitive chores, and will take on a wider range of tasks when they become more sophisticated, people will be needed to build, oversee and maintain robots, as well as come up with ideas for their use.

Far from predicting the obsolescence of human beings, robotics experts tend to speak in glowing terms of human abilities to see, sense, communicate and, most of all, respond quickly to unfamiliar or unexpected situations.

What's more, as Cetron puts it, "A robot can check inventory and even reorder parts, but it can't take a client out to dinner or negotiate a good price." graphics/ Robots "could mine gold without being tempted to steal it."