smkatz12 / xrsim

XrSim

Repository for simulating encounters in order to test various Urban Air Mobility (UAM) collision avoidance logics. Encounter files for this repository can be created using the UAMEncounterGen repository.

Quick Start Guide

Ensure that the following packages are installed in your current version of Julia: LinearAlgebra, Random, Distributions, GridInterpolations, and Mmap. This code was created and tested using Julia 1.1.

The following lines of code will simulate the encounters in the file data_files/enc_file.bin for an ownship equipped with Xr vertical logic (table located at data_files/Xr_vertical.bin) and an intruder that is unequipped.

sim = simulation()
sim.acs[1] = uam_vert(q_file = "../data_files/Xr_vertical.bin")
sim.enc_file = "data_files/enc_file.bin"
xr_sim!(sim)

The function xr_sim!(sim::SIMULATION) will modify the simulation output in the simulation object. For example, to access the trajectory of the ownship after running the lines above use:

sim.sim_out.ac1_trajectory

To visualize the output of a simulation, you can use UAMEncounterViewer.jl in an interactive Jupyter session. See EncounterViewerNotebook for details.

Type Descriptions

PHYSICAL_STATE - contains a position, velocity, acceleration (all 3D), and heading. Horizontal values are in meters. Vertical values are in feet. Heading is in radians. NOTE: all horizontal values in the code (until right before looking up in table) are in meters and vertical values in feet. This should probably be changed in the future.

OBSERVATION_STATE - contains just a position and velocity observation

MDP_STATE - Abstract type of states to be looked up in tables (VERT_STATE, SPEED_STATE)

BELIEF_STATE - Contains a vector of MDP_STATEs and their corresponding probabilies. probs should be a vector that sums to 1

KALMAN_FILTER - Used by the tracking module to keep track of current position estimate mean and covariance

TRACKER_HISTORY - Contains the observations received throughout an encounter and the progression of the tracker estimate

XR_TRAJECTORY - Vector of physical states

AIRCRAFT - abstract type that allows for a distinction between collision avoidance logics and properties. Each type of logic (unequipped, heuristic, vertical, speed, blended) has a corresponding aircraft type. Aircraft are initialized at the beginning of an encounter to contain a vectors of nominal accelerations to follow if no collision avoidance actions are taken. Throughout an encounter, an aircraft's current states (observation, physical, and belief) are updated. Aircraft with MDP-based logics contain their Q tables.

xrsim's Issues

UAMEncounterGen repository missing

Hello,

I wanted to test XrSim for a self-separation method I have been working on. I could not find the UAMEncounterGen. Is that open for the public?

Thanks