PID & Motion Profiles

Vortex includes professional-grade control structures for managing motor power based on sensor error.

PID

The vortex::PID class implements a Proportional-Integral-Derivative controller with anti-windup and exit conditions.

PIDSettings

struct PIDSettings {
    double kp, ki, kd;
    double i_max; // Integral anti-windup limit
    double slew;  // Output slew rate limit
};

ExitCondition

Used to determine when a movement is "settled".

struct ExitCondition {
    double error_threshold; // In inches or degrees
    int time_threshold;     // Milliseconds error must stay below threshold
    int timeout;            // Max time for the move
};

Methods

• update(double error): Calculates the motor power.
• isSettled(double error): Returns true if the exit conditions are met.

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TrapezoidalProfile

The TrapezoidalProfile class generates a smooth velocity curve (acceleration -> coast -> deceleration).

Constructor

TrapezoidalProfile(double max_speed, double accel, double decel);

calculate

Calculates the target speed for the current distance.

double calculate(double distance_to_target, double current_speed);

Vortex use this to clamp PID output, ensuring consistent acceleration regardless of how large the target distance is.