The room also has video cameras and a grid of beacons on the ceiling that emit ultrasound pulses denoting their location. (sciencedaily.com)
In their experiment, the UC Berkeley team powered up the passive sensors every 100 microseconds with six 540 - nanosecond ultrasound pulses, which gave them a continual, real - time readout. (sciencedaily.com)
The scientists measure the time required for ultrasound pulses to propagate through the concrete. (sciencedaily.com)