Yes
Exploratory robots are used in places where humans can't or shouldn't go.
So that humans don't have to do whatever is dangerous. Plus you can always build another of the exact robot. You can't do that with humans.
Robots have been used to replace humans in situations where a job is either too dangerous for a human or too costly. For example, robots have been used to explore Mars because it is too dangerous and costly to send humans to Mars at this time. They have also been used in some factories to cut down on costs and injuries associated with human workers.
Robots are currently used within the car industry in a lot of places to assemble cars and are gradually replacing humans within the field.
Robots are nothing more than a tool. Is a screwdriver dangerous? It certainly can be if used improperly. How about a bicycle spoke wrench? Improperly designed or implemented robots can be dangerous, just as your car can be dangerous.
Robots are used everywhere. They can dive deep in the sea where humans cannot go or on dangerous missions that endanger human lives
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Robots may replace humans in space exploration as a means to gather resource for future bases or to be used to build those base and robots are replacing humans in space right now, the mars rovers are robots.