ExpansionHubMotor.hpp

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// Copyright (c) FIRST and other WPILib contributors.
// Open Source Software; you can modify and/or share it under the terms of
// the WPILib BSD license file in the root directory of this project.
 
#pragma once
 
#include <memory>
 
#include "wpi/hardware/expansionhub/ExpansionHub.hpp"
#include "wpi/hardware/expansionhub/ExpansionHubPidConstants.hpp"
#include "wpi/nt/BooleanTopic.hpp"
#include "wpi/nt/DoubleTopic.hpp"
#include "wpi/nt/IntegerTopic.hpp"
#include "wpi/units/angle.hpp"
#include "wpi/units/current.hpp"
#include "wpi/units/time.hpp"
#include "wpi/units/voltage.hpp"
 
namespace wpi {
 
/** This class controls a specific motor and encoder hooked up to an
 * ExpansionHub. */
class ExpansionHubMotor {
 public:
  /**
   * Constructs a servo at the requested channel on a specific USB port.
   *
   * @param usbId The USB port ID the hub is connected to
   * @param channel The motor channel
   */
  ExpansionHubMotor(int usbId, int channel);
 
  ~ExpansionHubMotor() noexcept;
 
  /**
   * Sets the duty cycle.
   *
   * @param dutyCycle The duty cycle between -1 and 1 (sign indicates
   *     direction).
   */
  void SetDutyCycle(double dutyCycle);
 
  /**
   * Sets the voltage to run the motor at. This value will be continously scaled
   * to match the input voltage.
   *
   * @param voltage The voltage to drive the motor at
   */
  void SetVoltage(wpi::units::volt_t voltage);
 
  /**
   * Command the motor to drive to a specific position setpoint. This value will
   * be scaled by SetDistancePerCount and influenced by the PID constants.
   *
   * @param setpoint The position setpoint to drive the motor to
   */
  void SetPositionSetpoint(double setpoint);
 
  /**
   * Command the motor to drive to a specific velocity setpoint. This value will
   * be scaled by SetDistancePerCount and influenced by the PID constants.
   *
   * @param setpoint The velocity setpoint to drive the motor to
   */
  void SetVelocitySetpoint(double setpoint);
 
  /**
   * Sets if the motor output is enabled or not. Defaults to false.
   *
   * @param enabled True to enable, false to disable
   */
  void SetEnabled(bool enabled);
 
  /**
   * Sets if the motor should float or brake when 0 is commanded. Defaults to
   * false.
   *
   * @param floatOn0 True to float when commanded 0, false to brake
   */
  void SetFloatOn0(bool floatOn0);
 
  /**
   * Gets the current being pulled by the motor.
   *
   * @return Motor current
   */
  wpi::units::ampere_t GetCurrent() const;
 
  /**
   * Sets the distance per count of the encoder. Used to scale encoder readings.
   *
   * @param perCount The distance moved per count of the encoder
   */
  void SetDistancePerCount(double perCount);
 
  /**
   * Gets the current velocity of the motor encoder. Scaled into
   * distancePerCount units.
   *
   * @return Encoder velocity
   */
  double GetEncoderVelocity() const;
 
  /**
   * Gets the current position of the motor encoder. Scaled into
   * distancePerCount units.
   *
   * @return Encoder position
   */
  double GetEncoderPosition() const;
 
  /**
   * Sets if the motor and encoder should be reversed.
   *
   * @param reversed True to reverse encoder, false otherwise
   */
  void SetReversed(bool reversed);
 
  /** Reset the encoder count to 0. */
  void ResetEncoder();
 
  /**
   * Gets the PID constants object for velocity PID.
   *
   * @return Velocity PID constants object
   */
  ExpansionHubPidConstants& GetVelocityPidConstants();
 
  /**
   * Gets the PID constants object for position PID.
   *
   * @return Position PID constants object
   */
  ExpansionHubPidConstants& GetPositionPidConstants();
 
  /**
   * Gets if the underlying ExpansionHub is connected.
   *
   * @return True if hub is connected, otherwise false
   */
  bool IsHubConnected() { return m_hub.IsHubConnected(); }
 
  /**
   * Sets this motor to follow another motor on the same hub.
   *
   * This does not support following motors that are also followers.
   * Additionally, the direction of both motors will be the same.
   *
   * @param leader The motor to follow
   */
  void Follow(const ExpansionHubMotor& leader);
 
 private:
  ExpansionHub m_hub;
  int m_channel;
 
  wpi::nt::DoubleSubscriber m_encoderSubscriber;
  wpi::nt::DoubleSubscriber m_encoderVelocitySubscriber;
  wpi::nt::DoubleSubscriber m_currentSubscriber;
 
  wpi::nt::DoublePublisher m_setpointPublisher;
  wpi::nt::BooleanPublisher m_floatOn0Publisher;
  wpi::nt::BooleanPublisher m_enabledPublisher;
 
  wpi::nt::IntegerPublisher m_modePublisher;
 
  wpi::nt::BooleanPublisher m_reversedPublisher;
  wpi::nt::BooleanPublisher m_resetEncoderPublisher;
 
  wpi::nt::DoublePublisher m_distancePerCountPublisher;
 
  ExpansionHubPidConstants m_velocityPidConstants;
  ExpansionHubPidConstants m_positionPidConstants;
};
}  // namespace wpi