ACAS X for aircraft collision avoidance in 3D. For more information, please refer to https://www.ll.mit.edu/mission/aviation/publications/publication-files/atc-reports/Kochenderfer_2011_ATC-371_WW-21458.pdf
To use ACASX_3D, you will need two additional libraries: ECJ and MyMASON. You can find ECJ from https://cs.gmu.edu/~eclab/projects/ecj/. You can find MyMASON from https://github.com/xueyizou/MyMASON.git. Please refer to MASON's original homepage (http://cs.gmu.edu/~eclab/projects/mason/) for its usage.