Implements the rocket equations of motion (Eq. 5-14).
Functions¶
compute_derived¶
Compute derived quantities from state vector.
def compute_derived(
*,
y: Array,
earth: EarthParams,
stage: StageParams,
atmos: AtmosphereTable
) -> Derived:Returns:
- h: Altitude [m]
- rho: Atmospheric density [kg/m³]
- cs: Speed of sound [m/s]
- mach: Mach number
- drag: Drag force [N]
- q: Dynamic pressure [Pa]
rhs_general¶
General ODE right-hand side.
def rhs_general(
*,
t: Array,
y: Array,
earth: EarthParams,
stage: StageParams,
atmos: AtmosphereTable,
alpha: Array,
v_eps: Array
) -> Array:Equations implemented:
| Equation | Expression | Line |
|---|---|---|
| Eq. 5 | \(\dot{r} = v\sin\gamma\) | 69 |
| Eq. 6 | \(\dot{\lambda} = v\cos\gamma/r\) | 70 |
| Eq. 9 | Speed equation | 73 |
| Eq. 10 | Flight-path angle | 79 |
| Eq. 11 | Mass flow | 82 |
| Eq. 12 | Regularized \(1/v\) | 77 |
| Eq. 13 | Safe radius | 66 |
rhs_vertical¶
Vertical ascent phase (\(\gamma = \pi/2\)).
rhs_gravity_turn¶
Gravity turn phase (\(\alpha = 0\)).
rhs_coast¶
Coast phase (\(T = 0\)).
State Vector Indices¶
_R = 0 # Geocentric radius
_LAM = 1 # Downrange angle
_V = 2 # Speed magnitude
_GAMMA = 3 # Flight-path angle
_M = 4 # Mass