International researchers and the U.S. military alike have been developing robots for years, for purposes from bomb disposal to surveillance to carrying supplies. As the technology improves, the robots get more and more advanced. Here are a few of the latest designs:

Tiny Bird-Like Drones 

This video describes attempts by the U.S. Air Force to create flying drone vehicles that are indistinguishable from birds, bats, or even insects. Imagine a fake dragonfly with a camera in it that could track people's movements and provide surveillance from the sky. Luckily for us, they don't have a camera small and light enough to fit on the dragonfly's chassis. Yet.

Wall-Climbing Gecko-Inspired Robot

Researchers at Simon Fraser University unveiled this new machine in the journal 'Smart Materials and Structures'. It's a tank-like robot that can scale smooth walls, and the technology was inspired by the adhesive toe-pads of the gecko. Possible applications include inspecting aircraft, pipes, buildings and nuclear power plants, as well as search and rescue. But given the resemblance to a tank, it's hard not to picture it appearing from the roof of a nearby building with a gun turret looking for targets.

Petman Robot

Hey, remember the Terminator franchise? Where an army of killer robots that look like humans go berserk and start killing humans? No? Well, maybe the video above will refresh your memory. Created by Boston Dynamics, the Petman (Protection Ensemble Test Mannequin) robot is capable of running like a human, as well as doing push-ups and squats. Boston Dynamics (which is also responsible for designing military pack-bots BigDog and AlphaDog) says Petman is designed for "testing chemical protection clothing used by the U.S. Army". But they didn't rule out other applications. Like obeying the will of SkyNet?