collision#

Collision probability computation for conjunction assessment.

Compute probability of collision (Pc) between two space objects given their state vectors, position covariances, and hard-body radii. Implements the Foster 2D method (NASA CARA), Chan series expansion, and Alfano maximum Pc bound. Validates against the TraCSS CA verification dataset.

Installation#

opam install collision

Usage#

(* Quick Pc from a CDM *)
let pc = Collision.pc ~hbr:0.015 cdm in
Printf.printf "Pc = %e\n" pc

(* Step-by-step: project to conjunction plane, then compute *)
let enc = Collision.encounter_of_cdm ~hbr:0.015 cdm in
let pc_foster = Collision.pc_foster enc in
let pc_max = Collision.pc_max enc in
Printf.printf "Foster Pc: %e, Max Pc bound: %e\n" pc_foster pc_max

API Overview#

• type encounter -- Conjunction geometry in the encounter plane: miss_x, miss_y, sigma_x, sigma_y, hbr
• encounter_of_cdm -- Project CDM conjunction geometry onto the conjunction plane
• pc_foster -- 2D Pc via Gauss-Legendre quadrature (NASA CARA standard method)
• pc_chan -- Pc via Chan series expansion
• pc_max -- Upper bound: hbr^2 / (2 * sigma_x * sigma_y)
• pc -- Convenience: project + Foster in one call

License#

ISC