centripetal_acceleration_constraint.h

#pragma once
 
#include <memory>
 
#include "core/math/trajectory/constraints/trajectory_constraint.h"
#include "core/math/units.h"
 
using namespace units::literals;
 
/**
 * @brief Trajectory constraint that limits maximum velocity to prevent excessive centripetal
 * acceleration.
 */
class CentripetalAccelerationConstraint : public TrajectoryConstraint {
 public:
  /**
   * @brief Constructs a CentripetalAccelerationConstraint.
   * @param max_centripetal_acceleration Maximum allowed centripetal acceleration.
   */
  explicit CentripetalAccelerationConstraint(units::Acceleration max_centripetal_acceleration)
      : max_centripetal_acceleration_(max_centripetal_acceleration) {}
 
  /**
   * @brief Computes maximum allowed velocity based on path curvature and centripetal acceleration
   * limits.
   * @param pose 2D position and orientation.
   * @param curvature Path curvature in rad/meter.
   * @param velocity Candidate linear velocity.
   * @return Constrained units::Velocity limit.
   */
  units::Velocity max_velocity(
      const Pose2d& pose, units::Curvature curvature, units::Velocity velocity
  ) const override {
    if (units::abs(curvature) < 1e-9_radpm) {
      return units::Velocity(std::numeric_limits<double>::max());
    }
    return sqrt(max_centripetal_acceleration_ / units::abs(curvature / 1_rad));
  }
 
  /**
   * @brief Computes minimum and maximum allowed linear accelerations.
   * @param pose 2D position and orientation.
   * @param curvature Path curvature in rad/meter.
   * @param speed Current scalar speed.
   * @return MinMax acceleration bounds struct.
   */
  MinMax min_max_acceleration(
      const Pose2d& pose, units::Curvature curvature, units::Velocity speed
  ) const override {
    return {};
  }
 
  /**
   * @brief Creates an independent copy of this constraint.
   * @return Unique pointer to cloned CentripetalAccelerationConstraint instance.
   */
  std::unique_ptr<TrajectoryConstraint> clone() const override {
    return std::unique_ptr<TrajectoryConstraint>(new CentripetalAccelerationConstraint(*this));
  }
 
 private:
  units::Acceleration max_centripetal_acceleration_;  ///< Maximum centripetal acceleration
};