Robot wardens are about to join the ranks of South Korea's prison service.
A jail in the eastern city of Pohang plans to run a month-long trial with three of the automatons in March.
The machines will monitor inmates for abnormal behaviour. Researchers say they will help reduce the workload for other guards.
Business leaders believe the field has the potential to become a major export industry.
The three 1.5m robots in the trial have been developed by the Asian Forum for Corrections, a South Korean research group specialising in criminality and prison policies. It says the robots move on four wheels and have cameras and sensors that allow them to detect risky behaviour such as violence and suicide.
Professor Lee Baik-Chu, of Kyonggi University, says the robots will alert human guards if they discover a problem.
"We're almost done with creating its key operating system. We are now working on refining details to make it look more friendly to inmates," the professor says.
The one-month trial will cost £554,000 ($1.2 million) and is sponsored by the South Korean Government.