Amazon revealed a camera-equipped home robot Tuesday that users can deploy to patrol their houses, a device that one of the project's developers said was making science fiction a reality.

The tech giant cheered the "Astro" robot as a breakthrough for security and convenience, but digital watchdogs raised concerns for potential risks to people's most private moments at home.

Astro is a roughly two-foot (60 centimeters) tall and 20-pound (nine kilograms) device that can map out a house floor plan and obey commands to go to a specific place to take a closer look with its telescoping camera.

"Now when you are away, you can use it to proactively patrol your home and investigate activity," Amazon executive Dave Limp said in a product launch clip.

The device, which can work with Amazon's digital home assistant Alexa, can be taught to recognize faces and learn the habits of household members.

Digital privacy trade-off ?

Amazon said Astro could also be useful to help remotely check on elderly relatives or deliver reminders for certain activities.

"It's taking science fiction and making it a reality," Suri Maddhula, who worked on the project, said in a video.

Matthew Guariglia, a policy analyst at digital watchdog group Electronic Frontier Foundation, raised concerns about the device potentially allowing hackers to see into a user's home or police seeking access to it via a search warrant.

"There are some scenarios in which (Astro) could be useful; there are some scenarios in which a surveillance camera on your house could be useful, too," he told AFP.

"But the problem is that you need to know that it comes off with a trade-off of vulnerability," he added.

Limp, the Amazon senior vice president for devices and services, in a call with journalists said Astro has built-in features to guard against abuses.

He said users can shut down Astro's cameras and microphones, also noting that the device issues a warning sound and message on its display when someone is trying to access the cameras remotely.

"If somebody hacked your account or something, and that could be a bad person obviously, we want to notify anyone that might be at home," he said.

He went on to say that Amazon does not have remote access to the cameras on its machines, and thus "would never allow a police department or a first responder to have access to that device."