Struct Environment 

pub struct Environment { /* private fields */ }

Where and in what weather a rocket flies: a launch site, an atmosphere and a wind.

Environment::new puts the site on the WGS 84 ellipsoid, with the 1976 US Standard Atmosphere and no wind. The with_ methods change the weather. For what this type doesn’t offer, such as a geoid undulation, build an hpr_sim::Environment and wrap it with Environment::from_sim.

use hpr::Environment;

// Spaceport America, 1,400 m up, with 5 m/s of wind from the west.
let environment = Environment::new(32.99, -106.97, 1400.0)?.with_constant_wind(5.0, 270.0)?;
assert_eq!(environment.sim().site().height_m, 1400.0);

Implementations

impl Environment

pub fn new( latitude_deg: f64, longitude_deg: f64, elevation_m: f64, ) -> Result<Self, Error>

A launch site at latitude latitude_deg (degrees north), longitude longitude_deg (degrees east) and elevation elevation_m, with the 1976 US Standard Atmosphere and no wind.

The elevation is taken as both the site’s height above mean sea level, which the atmosphere and wind are read at, and its height above the WGS 84 ellipsoid, which the flight’s position is measured from, as if the geoid undulation, the gap between the two, were zero; hpr has no geoid model. The air is read where you said; the site’s gravity is off by the free-air gradient, about 3.1 µm/s² per meter of undulation. To give an undulation N, build an hpr_sim::Environment on the site’s ellipsoidal height h = H + N, set N with hpr_sim::Environment::with_geoid_undulation_m, and wrap it with Environment::from_sim; the air is then read at H. Heights in a flight’s results are above the site. Longitude is positive east, so a site in the Americas has a negative one.

Errors

Error::Core for a latitude outside [−90°, 90°] or a value that isn’t finite.

pub fn with_wind(self, wind: impl Wind + 'static) -> Self

The same place and atmosphere, with wind in place of the wind: any Wind, such as hpr_atmos’s power law, log law or layers by height, or a model of your own.

pub fn with_constant_wind( self, speed_m_s: f64, from_deg: f64, ) -> Result<Self, Error>

The same place and atmosphere, with a wind of speed_m_s at every height, blowing from from_deg: the direction it comes from, clockwise from true north (270° is a west wind).

Errors

Error::Domain for a direction that isn’t finite; Error::Atmos for a negative or non-finite speed.

pub fn with_atmosphere(self, atmosphere: impl Atmosphere + 'static) -> Self

The same place and wind, with atmosphere in place of the standard one: any Atmosphere, such as a balloon sounding’s levels (hpr_atmos::SoundingProfile), or a model of your own.

pub fn with_gravity(self, gravity: GravityModel) -> Result<Self, Error>

The same place and weather, with gravity evaluated by gravity in place of the default, GravityModel::Ellipsoidal: the full normal gravity vector at the rocket’s position. GravityModel::VerticalTaylor is RocketPy’s formula, for like-for-like comparisons with it; GravityModel has the rest. The Earth’s rotation is kept.

use hpr::Environment;
use hpr::hpr_core::earth::GravityModel;

let environment =
    Environment::new(32.99, -106.97, 1400.0)?.with_gravity(GravityModel::VerticalTaylor)?;
assert_eq!(environment.sim().earth.gravity_model(), GravityModel::VerticalTaylor);

Errors

Error::Core for a constant gravity that is negative or not finite.

pub fn from_sim(sim: Environment) -> Self

An environment built with hpr_sim directly.

pub fn sim(&self) -> &Environment

The hpr_sim::Environment this wraps.

Trait Implementations

impl Clone for Environment

fn clone(&self) -> Environment

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Environment

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.