Add machine workshop, typed logic, mechanics and sensor-driven ECUs

include/FluidSim/Mechanics.hpp

@@ -0,0 +1,54 @@
+#pragma once
+#include <cstdint>
+#include <memory>
+
+namespace fluidsim::port {
+// Rotational quantities use SI: rad, rad/s, N m, kg m2, J and W.
+enum class DriveMode {Torque,Speed};
+struct ShaftParameters {
+    double inertia{.15},initial_speed{},initial_angle{};
+    double friction_constant{},friction_viscous{},friction_quadratic{};
+    bool forward_only{};
+};
+struct DriveParameters {DriveMode mode{DriveMode::Torque};double command{};bool enabled{true};};
+struct BrakeParameters {double constant{},viscous{},quadratic{};bool enabled{true};};
+struct ShaftState {
+    std::uint32_t id{};
+    double angle{},previous_angle{},speed{},inertia{},kinetic_energy{};
+    double net_torque{},source_torque{},external_torque{},friction_torque{},brake_torque{},constraint_torque{};
+    double external_work{},drive_work{},friction_loss{},brake_loss{},initial_energy{};
+    // initial_energy + external_work + drive_work = kinetic_energy + losses.
+};
+struct DriveState {
+    std::uint32_t id{},shaft{};
+    double torque{},power{},work{};
+};
+struct BrakeState {
+    std::uint32_t id{},shaft{};
+    double torque{},power{},loss{}; // Torque on shaft signed; absorbed power >= 0.
+};
+// Independent rigid shaft nodes. Gears and clutches will couple these nodes;
+// direct attachment adds torque or inertia to one named node exactly once.
+class MechanicalSystem {
+public:
+    MechanicalSystem();
+    ~MechanicalSystem();
+    MechanicalSystem(const MechanicalSystem&)=delete;
+    MechanicalSystem& operator=(const MechanicalSystem&)=delete;
+    void add_shaft(std::uint32_t,const ShaftParameters&);
+    void add_flywheel(std::uint32_t id,std::uint32_t shaft,double inertia);
+    void add_drive(std::uint32_t id,std::uint32_t shaft,const DriveParameters&);
+    void add_brake(std::uint32_t id,std::uint32_t shaft,const BrakeParameters&);
+    void set_drive(std::uint32_t,const DriveParameters&);
+    void set_brake(std::uint32_t,const BrakeParameters&);
+    void set_friction(std::uint32_t shaft,double constant,double viscous,double quadratic);
+    void add_torque(std::uint32_t shaft,double torque);
+    void step(double dt);
+    const ShaftState& shaft(std::uint32_t)const;
+    const DriveState& drive(std::uint32_t)const;
+    const BrakeState& brake(std::uint32_t)const;
+private:
+    struct Impl;
+    std::unique_ptr<Impl> impl_;
+};
+}