There is a contest run in Australia called the "UAV Outback rescue" https://uavchallenge.org/ It's run by Australia's peak scientific body, the CSIRO so the results are pretty rigorous.
The scenario is Joe is lost and incapacitated in the Australian bush. "Joe" is a human sized dummy with a (very) small infra red source under his clothing. He needs to be found and then have something done. He is located within an area of about 50 sq km.
The requirement has always been the aircraft must be totally autonomous from take-off through to landing - and that includes finding Joe. In the previous challenge, once Joe was fond the aircraft had to land beside him, and take off again - in an area it had never seen before.
About 6 years ago Andrew Tridgell (original author of Samba and Rsync) joined Canberra UAV (an amateur group of UAV enthusiasts), and started working on the Ardupilot AUV software Canberra UAV used in future attempts at the competition. At the time nobody had completed the challenge. After Andrew joined Canberra UAV, Canberra UAV completed the challenge every time (and indeed until 2018 was the only team to complete it) forcing the CSIRO to up the difficulty for the next competition to be held.
The location algorithm has been pretty simple in all cases - this is a group of amateurs who could not use expensive LIDAR's. From memory it's multi pass. The first pass happens from relatively high, and then promising signatures (which are barely more than a pixel) and then investigated more closely.
The scenario is Joe is lost and incapacitated in the Australian bush. "Joe" is a human sized dummy with a (very) small infra red source under his clothing. He needs to be found and then have something done. He is located within an area of about 50 sq km.
The requirement has always been the aircraft must be totally autonomous from take-off through to landing - and that includes finding Joe. In the previous challenge, once Joe was fond the aircraft had to land beside him, and take off again - in an area it had never seen before.
About 6 years ago Andrew Tridgell (original author of Samba and Rsync) joined Canberra UAV (an amateur group of UAV enthusiasts), and started working on the Ardupilot AUV software Canberra UAV used in future attempts at the competition. At the time nobody had completed the challenge. After Andrew joined Canberra UAV, Canberra UAV completed the challenge every time (and indeed until 2018 was the only team to complete it) forcing the CSIRO to up the difficulty for the next competition to be held.
The location algorithm has been pretty simple in all cases - this is a group of amateurs who could not use expensive LIDAR's. From memory it's multi pass. The first pass happens from relatively high, and then promising signatures (which are barely more than a pixel) and then investigated more closely.