When buildings collapse, it is extremely difficult to safely locate and rescue people trapped inside. Victims may be wedged into small spaces, and unstable rubble could collapse on rescue workers. An alternative to human rescue workers may be robotic cockroaches. Real cockroaches are protected by strong yet flexible exoskeletons. They can also flatten their bodies through tiny cracks. A robotics researcher from Harvard University and a biomechanics expert from the University of California, Berkeley, were inspired to create mini robots that have the same features. The roach robots can squeeze through small spaces and skitter over unstable environments. Fitted with cameras and microphones, they could be used in disasters to locate victims. What is the main idea of the passage?