Hundreds of Facebook workers wearing special glasses that record everything they see and hear will venture into public and private spaces in order to research the dangers of augmented reality (AR).
In a live-streamed broadcast, the social media giant said it would send out specially trained employees and contractors to gather video, audio, location and eye-tracking data starting this month.
Andrew Bosworth, Facebook's head of AR, vowed to protect bystanders' privacy by blurring all faces and licence plates before they are used for research and keeping the workers out of "sensitive spaces" such as toilets and prayer rooms.
The glasses, known as "Project Aria", are designed to alert Facebook to moral and privacy problems before it launches a real AR headset, as well as gathering vast amounts of data to train the artificial intelligence (AI) systems that will power any such product.
The company said the project was about "figuring out the right privacy and safety and policy model, long before we bring AR glasses to the world".
Even so, the technology, combined with Facebook's history of privacy scandals, risks creating a backlash of the kind that hobbled Google's previous attempt at building AR glasses, Google Glass.
Facebook's chief executive Mark Zuckerberg also confirmed that it will launch a pair of "smart glasses" designed by the prolific eyewear maker Ray-Ban next year.
Mr Bosworth said: "New technology often has unintended consequences and negative externalities, and our job is to get ahead of ours.
"In order to wear the research glasses, people undergo training on when and where they can gather data. Sensitive places like restrooms or prayer rooms are obviously off limits.
"Before data we collect in public is used for research, that data is quarantined, and faces and license plates are blurred. Like a [Google] mapping car, all participants will be easily identifiable by their clothing...
"We strive to do what's right for our community, individuals and our business. When faced with these trade-offs we prioritise our community."
He added that Facebook would offer two grants of $1m (£770,000) each for outside research into how AR glasses could harm or endanger people who do not wear them, especially from "vulnerable communities".
Project Aria appears to be part of a grand plan by Facebook to create a comprehensive digital map of the world to help its future AI systems understand and categorise what they are seeing, which is necessary for AR to work.
The research glasses carry three front-facing cameras, seven directional microphones, two inward-facing cameras to observe what wearers are looking at and a package of accelerometers and gyroscopes to track the position of their head.
Peter Rojas, a partner at the venture capital firm Betaworks Ventures, said that allaying privacy concerns will be crucial for Facebook's AR products to compete with those of rivals such as Apple, which is developing a similar system.
He said: "Winning in consumer AR won’t just be about who has the best technology. Apple’s big advantage is that it is probably the only big tech company that consumers will trust when it comes to privacy issues related to wearing AR glasses.
"I think the actual risks are low, in that I don’t think Facebook employees are going to have ready access to camera footage of end users... [but] being around someone with Facebook AR glasses will make a lot of people uncomfortable, like Google Glass did."