For public safety agencies, sniffing out explosives and other contraband is a tricky task. Handheld explosive detectors can be as small as a purse, but still must be manually operated. Permanently mounted sensors need to be even bigger. Dogs are useful in some scenarios, but they're expensive to deploy en masse and must always have a handler.
The post This Wireless Explosives Detector Is the Size of a Postage Stamp appeared first on WIRED.