Expand description
Motor mounts, configurations and the assembled rocket: the structure with its motors placed, and its mass properties through the burn.
Placement. A motor’s axis runs forward from its nozzle exit (hpr_motor::mass). In a
mount whose axial extent ends at station s_aft, the nozzle exit sits at station
s_aft + overhang, on the mount’s axis (an inner tube’s radial offset and angle, or the body
axis). A motor element at z_m along the motor axis is then at body
(x_mount, y_mount, −(s_aft + overhang) + z_m) (MassProperties::from_motor_element).
Composition. The rocket at time t is the structure (Layout::structure) combined with
each motor’s loaded, burning or spent mass properties (SolidMotor::state) at its own time
since ignition. Assembly::mass_properties lights every motor at t = 0;
Assembly::mass_properties_lit takes each motor’s ignition time (Ignition, resolved by
Assembly::ignition_times_s), and a motor not yet lit is loaded. This is RocketPy’s
composition (Rocket.total_mass, center_of_mass, and the inertias of
rocketpy/rocket/rocket.py), checked against RocketPy 1.13.0 in the tests.
See docs/physics/design.md.
Structs§
- Assembly
- A rocket with one configuration’s motors in place.
- Configuration
- A set of motors to fly with: at most one per mount. A mount that is a cluster
(
InnerTube::cluster_m) takes its motor in every tube. - LaidOut
- A copy of a design and its layout, laid out once by
Rocket::lay_out, to check it and assemble it (LaidOut::into_assembly) without laying it out again. Its fields are private, so the layout is always the design’s own. - Motor
Mount - Makes a body tube or inner tube a motor mount.
- Mounted
Motor - A motor in a mount.
- Placed
Motor - A motor placed in the rocket: one per tube of its mount, so a cluster’s mount gives several, one after another in the order of its tubes.