US military project to use machine learning
Project Maven (officially Algorithmic Warfare Cross Functional Team) is a Pentagon project involving using machine learning and data fusion to process data from many sources, identify potential targets, display information through a user interface, and transmit human decisions to weapon systems, among other functions. It began in 2017. Since 2021, it had been used in multiple military conflicts involving the US.
Origins.
Initially, the effort was led by Robert O. Work who was concerned about China's military use of the emerging technology. Reportedly, Pentagon development stops short of acting as an AI weapons system capable of firing on self-designated targets. The project was established in a memo by the U.S. Deputy Secretary of Defense on 26 April 2017. 
At the second Defense One Tech Summit in July 2017, Cukor also said that the investment in a "deliberate workflow process" was funded by the Department [of Defense] through its "rapid acquisition authorities" for about "the next 36 months".
According to Lt. Gen. of the United States Air Force Jack Shanahan in November 2017, it is "designed to be that pilot project, that pathfinder, that spark that kindles the flame front of artificial intelligence across the rest of the [Defense] Department". Its chief, U.S. Marine Corps Col. Drew Cukor, said: "People and computers will work symbiotically to increase the ability of weapon systems to detect objects." Project Maven has been noted by allies, such as Australia's Ian Langford, for the ability to identify adversaries by harvesting data from sensors on UAVs and satellite. 
In 2022, the National Geospatial-Intelligence Agency took over Project Maven.
Technology.
Project Maven involves data fusion. For data fusion, the Pentagon originally collaborated with Google, but in 2018, Google employees, including Meredith Whittaker, staged walkouts protesting Google's involvement in Project Maven. Subsequently, Google did not renew the contract with Pentagon.
Companies that have contributed to the data fusion include Palantir Technologies, Amazon Web Services, ECS Federal, L3Harris Technologies, Maxar Technologies, Microsoft and Sierra Nevada Corporation. The main data-fusion platform is made by Palantir. At least 21 private companies had been involved.
The data sources include photographs, satellite imagery, geolocation data (IP address, geotag, metadata, etc) from communications intercepts, infrared sensors, synthetic-aperture radar, etc. Machine learning systems, including object recognition systems, process the data and identify potential targets, such as enemy tanks or location of new military facility. The training dataset included at least 4 million images of military objects such as warships, labelled by humans. The user interface is called Maven Smart System. It could display information such as aircraft movements, logistics, locations of key personnel, locations on the no-strike list, ships, etc. Yellow-outlined boxes show potential targets. Blue-outlined boxes show friendly forces or no-strike zones. It could also transmit, directly to weapons, a human decision to fire weapons.
Applications.
Scarlet Dragon exercises.
The 18th Airborne Corps is the main tester of Project Maven. With collaborating arms organization in US and UK, it has used Maven and weapons systems connected to it to strike targets from bombers, fighter jets and drones.
Beginning in 2020, Maven was used for live-fire exercises ("Scarlet Dragon exercises"). The first took place at Fort Liberty. An AI system identified a tank in satellite images, the human approved, and the AI system signaled an M142 HIMARS to strike the target (in this case, a decommissioned tank). It was the first AI-enabled artillery strike in the US army.
There are 6 steps in the kill chain: identify, locate, filter down to the lawful valid targets, prioritize, assign them to firing units, and fire. Of these 6 steps, Maven can perform 4. A senior targeting officer estimates that with Maven, he could decide on 80 targets per hour, vs 30 targets per hour without Maven. The efficiency was comparable with the targeting cell used during Operation Iraqi Freedom, but whereas the OIF used a targeting cell with roughly 2000 staff, the 18th Airborne used a targeting cell with 20 people.
Use in actual conflicts.
In the 2021 Kabul airlift, Maven was used to display the situation on the ground. It could simultaneously display data feeds, such as aircraft movements, logistics, threats and locations of key personnel such as Chris Donahue.
In the 2022 Russian invasion of Ukraine, Maven was used to display information on Ukrainian will to resist Russian forces, and locations of Russian equipment.
In February 2024, Maven was used for narrowing targets for airstrikes in Iraq and Syria. It was also used for locating rocket launchers in Yemen and surface vessels in the Red Sea, some of which were destroyed in February 2024 according to CENTCOM.