Following years of testing and multi-million dollar investment, the US Military has announced it has shelved plans to deploy Google's robotic dogs due to noise concerns.
Known as 'the big dog', the Legged Squad Support System (LS3) was designed in partnership with Boston Dynamics, a robotics company owned by Google.
The machines, also referred to as robotic mules, are capable of carrying up to 400 pounds (181kg) of weight and can follow soldiers through varying terrain.
But according to the US Marines, the engine which powers the big dogs is too loud and could give away troops' positions.
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Kyle Olson, a spokesman for the Marine Corps Warfighting Lab, told Military.com: "As Marines were using it, there was the challenge of seeing the potential possibility because of the limitations of the robot itself.
"They took it as it was: a loud robot that's going to give away their position."
The petrol-powered engine, said to sound like a lawnmower, was not the only concern raised by the military.
Other problems include how to repair the machines, and how to integrate them into traditional Marine patrol.
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LS3 was the result of a 2010 contract between the Pentagon's research arm, the Defense Advanced Research Projects Agency (DARPA), and Boston Dynamics.
The project cost around $42 million (£28 million) in total.
After problems with the big dog became apparent, a smaller, quieter, electric-powered alternative known as 'Spot' was developed.
However, the US military has also shelved 'Spot' which could only carry weight of up to 40 pounds (18kg).
Google has long said it will move away from its military contracts although the Military's Warfighting lab continues to experiment with other unmanned machines.