servo_calcs.h

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/*******************************************************************************
 *      Title     : servo_calcs.h
 *      Project   : moveit_servo
 *      Created   : 1/11/2019
 *      Author    : Brian O'Neil, Andy Zelenak, Blake Anderson
 *
 * BSD 3-Clause License
 *
 * Copyright (c) 2019, Los Alamos National Security, LLC
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * * Neither the name of the copyright holder nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 *******************************************************************************/
 
#pragma once
 
// C++
#include <condition_variable>
#include <mutex>
#include <thread>
#include <atomic>
 
// ROS
#include <control_msgs/msg/joint_jog.hpp>
#include <geometry_msgs/msg/twist_stamped.hpp>
#include <moveit/planning_scene_monitor/planning_scene_monitor.h>
#include <moveit/robot_model_loader/robot_model_loader.h>
#include <moveit_msgs/srv/change_drift_dimensions.hpp>
#include <moveit_msgs/srv/change_control_dimensions.hpp>
#include <pluginlib/class_loader.hpp>
#include <rclcpp/rclcpp.hpp>
#include <sensor_msgs/msg/joint_state.hpp>
#include <std_msgs/msg/float64.hpp>
#include <std_msgs/msg/float64_multi_array.hpp>
#include <std_msgs/msg/int8.hpp>
#include <std_srvs/srv/empty.hpp>
#include <trajectory_msgs/msg/joint_trajectory.hpp>
 
// moveit_core
#include <moveit/kinematics_base/kinematics_base.h>
 
// moveit_servo
#include <moveit_servo/servo_parameters.h>
#include <moveit_servo/status_codes.h>
#include <moveit/online_signal_smoothing/smoothing_base_class.h>
 
namespace moveit_servo
{
enum class ServoType
{
  CARTESIAN_SPACE,
  JOINT_SPACE
};
 
class ServoCalcs
{
public:
  ServoCalcs(const rclcpp::Node::SharedPtr& node,
             const std::shared_ptr<const moveit_servo::ServoParameters>& parameters,
             const planning_scene_monitor::PlanningSceneMonitorPtr& planning_scene_monitor);
 
  ~ServoCalcs();
 
  void start();
 
  bool getCommandFrameTransform(Eigen::Isometry3d& transform);
  bool getCommandFrameTransform(geometry_msgs::msg::TransformStamped& transform);
 
  bool getEEFrameTransform(Eigen::Isometry3d& transform);
  bool getEEFrameTransform(geometry_msgs::msg::TransformStamped& transform);
 
  void setPaused(bool paused);
 
protected:
  void mainCalcLoop();
 
  void calculateSingleIteration();
 
  void stop();
 
  bool cartesianServoCalcs(geometry_msgs::msg::TwistStamped& cmd,
                           trajectory_msgs::msg::JointTrajectory& joint_trajectory);
 
  bool jointServoCalcs(const control_msgs::msg::JointJog& cmd, trajectory_msgs::msg::JointTrajectory& joint_trajectory);
 
  void updateJoints();
 
  bool checkValidCommand(const control_msgs::msg::JointJog& cmd);
 
  bool checkValidCommand(const geometry_msgs::msg::TwistStamped& cmd);
 
  Eigen::VectorXd scaleCartesianCommand(const geometry_msgs::msg::TwistStamped& command);
 
  Eigen::VectorXd scaleJointCommand(const control_msgs::msg::JointJog& command);
 
  void filteredHalt(trajectory_msgs::msg::JointTrajectory& joint_trajectory);
 
  void suddenHalt(sensor_msgs::msg::JointState& joint_state,
                  const std::vector<const moveit::core::JointModel*>& joints_to_halt) const;
 
  std::vector<const moveit::core::JointModel*> enforcePositionLimits(sensor_msgs::msg::JointState& joint_state) const;
 
  void composeJointTrajMessage(const sensor_msgs::msg::JointState& joint_state,
                               trajectory_msgs::msg::JointTrajectory& joint_trajectory);
 
  void resetLowPassFilters(const sensor_msgs::msg::JointState& joint_state);
 
  bool internalServoUpdate(Eigen::ArrayXd& delta_theta, trajectory_msgs::msg::JointTrajectory& joint_trajectory,
                           const ServoType servo_type);
 
  bool applyJointUpdate(const Eigen::ArrayXd& delta_theta, sensor_msgs::msg::JointState& joint_state);
 
  void insertRedundantPointsIntoTrajectory(trajectory_msgs::msg::JointTrajectory& joint_trajectory, int count) const;
 
  void removeDimension(Eigen::MatrixXd& matrix, Eigen::VectorXd& delta_x, unsigned int row_to_remove) const;
 
  void removeDriftDimensions(Eigen::MatrixXd& matrix, Eigen::VectorXd& delta_x);
 
  void enforceControlDimensions(geometry_msgs::msg::TwistStamped& command);
 
  /* \brief Callback for joint subsription */
  void jointStateCB(const sensor_msgs::msg::JointState::SharedPtr msg);
 
  /* \brief Command callbacks */
  void twistStampedCB(const geometry_msgs::msg::TwistStamped::ConstSharedPtr& msg);
  void jointCmdCB(const control_msgs::msg::JointJog::ConstSharedPtr& msg);
  void collisionVelocityScaleCB(const std_msgs::msg::Float64::ConstSharedPtr& msg);
 
  void changeDriftDimensions(const std::shared_ptr<moveit_msgs::srv::ChangeDriftDimensions::Request>& req,
                             const std::shared_ptr<moveit_msgs::srv::ChangeDriftDimensions::Response>& res);
 
  // Service callback for changing servoing dimensions
  void changeControlDimensions(const std::shared_ptr<moveit_msgs::srv::ChangeControlDimensions::Request>& req,
                               const std::shared_ptr<moveit_msgs::srv::ChangeControlDimensions::Response>& res);
 
  bool resetServoStatus(const std::shared_ptr<std_srvs::srv::Empty::Request>& req,
                        const std::shared_ptr<std_srvs::srv::Empty::Response>& res);
 
  // Pointer to the ROS node
  std::shared_ptr<rclcpp::Node> node_;
 
  // Parameters from yaml
  const std::shared_ptr<const moveit_servo::ServoParameters> parameters_;
 
  // Pointer to the collision environment
  planning_scene_monitor::PlanningSceneMonitorPtr planning_scene_monitor_;
 
  // Track the number of cycles during which motion has not occurred.
  // Will avoid re-publishing zero velocities endlessly.
  int zero_velocity_count_ = 0;
 
  // Flag for staying inactive while there are no incoming commands
  bool wait_for_servo_commands_ = true;
 
  // Flag saying if the filters were updated during the timer callback
  bool updated_filters_ = false;
 
  // Nonzero status flags
  bool have_nonzero_twist_stamped_ = false;
  bool have_nonzero_joint_command_ = false;
  bool have_nonzero_command_ = false;
 
  // Incoming command messages
  geometry_msgs::msg::TwistStamped twist_stamped_cmd_;
  control_msgs::msg::JointJog joint_servo_cmd_;
 
  const moveit::core::JointModelGroup* joint_model_group_;
 
  moveit::core::RobotStatePtr current_state_;
 
  // (mutex protected below)
  // internal_joint_state_ is used in servo calculations. It shouldn't be relied on to be accurate.
  // original_joint_state_ is the same as incoming_joint_state_ except it only contains the joints the servo node acts
  // on.
  sensor_msgs::msg::JointState internal_joint_state_, original_joint_state_;
  std::map<std::string, std::size_t> joint_state_name_map_;
 
  // Smoothing algorithm (loads a plugin)
  std::shared_ptr<online_signal_smoothing::SmoothingBaseClass> smoother_;
 
  trajectory_msgs::msg::JointTrajectory::SharedPtr last_sent_command_;
 
  // ROS
  rclcpp::Subscription<sensor_msgs::msg::JointState>::SharedPtr joint_state_sub_;
  rclcpp::Subscription<geometry_msgs::msg::TwistStamped>::SharedPtr twist_stamped_sub_;
  rclcpp::Subscription<control_msgs::msg::JointJog>::SharedPtr joint_cmd_sub_;
  rclcpp::Subscription<std_msgs::msg::Float64>::SharedPtr collision_velocity_scale_sub_;
  rclcpp::Publisher<std_msgs::msg::Int8>::SharedPtr status_pub_;
  rclcpp::Publisher<trajectory_msgs::msg::JointTrajectory>::SharedPtr trajectory_outgoing_cmd_pub_;
  rclcpp::Publisher<std_msgs::msg::Float64MultiArray>::SharedPtr multiarray_outgoing_cmd_pub_;
  rclcpp::Service<moveit_msgs::srv::ChangeControlDimensions>::SharedPtr control_dimensions_server_;
  rclcpp::Service<moveit_msgs::srv::ChangeDriftDimensions>::SharedPtr drift_dimensions_server_;
  rclcpp::Service<std_srvs::srv::Empty>::SharedPtr reset_servo_status_;
 
  // Main tracking / result publisher loop
  std::thread thread_;
  bool stop_requested_;
  std::atomic<bool> done_stopping_;
 
  // Status
  StatusCode status_ = StatusCode::NO_WARNING;
  std::atomic<bool> paused_;
  bool twist_command_is_stale_ = false;
  bool joint_command_is_stale_ = false;
  bool ok_to_publish_ = false;
  double collision_velocity_scale_ = 1.0;
 
  // Use ArrayXd type to enable more coefficient-wise operations
  Eigen::ArrayXd delta_theta_;
 
  const int gazebo_redundant_message_count_ = 30;
 
  unsigned int num_joints_;
 
  // True -> allow drift in this dimension. In the command frame. [x, y, z, roll, pitch, yaw]
  std::array<bool, 6> drift_dimensions_ = { { false, false, false, false, false, false } };
 
  // The dimensions to control. In the command frame. [x, y, z, roll, pitch, yaw]
  std::array<bool, 6> control_dimensions_ = { { true, true, true, true, true, true } };
 
  // main_loop_mutex_ is used to protect the input state and dynamic parameters
  mutable std::mutex main_loop_mutex_;
  Eigen::Isometry3d tf_moveit_to_robot_cmd_frame_;
  Eigen::Isometry3d tf_moveit_to_ee_frame_;
  geometry_msgs::msg::TwistStamped::ConstSharedPtr latest_twist_stamped_;
  control_msgs::msg::JointJog::ConstSharedPtr latest_joint_cmd_;
  rclcpp::Time latest_twist_command_stamp_ = rclcpp::Time(0., RCL_ROS_TIME);
  rclcpp::Time latest_joint_command_stamp_ = rclcpp::Time(0., RCL_ROS_TIME);
  bool latest_twist_cmd_is_nonzero_ = false;
  bool latest_joint_cmd_is_nonzero_ = false;
 
  // input condition variable used for low latency mode
  std::condition_variable input_cv_;
  bool new_input_cmd_ = false;
 
  // dynamic parameters
  std::string robot_link_command_frame_;
  rcl_interfaces::msg::SetParametersResult robotLinkCommandFrameCallback(const rclcpp::Parameter& parameter);
 
  // Load a smoothing plugin
  pluginlib::ClassLoader<online_signal_smoothing::SmoothingBaseClass> smoothing_loader_;
 
  kinematics::KinematicsBaseConstPtr ik_solver_;
  Eigen::Isometry3d ik_base_to_tip_frame_;
  bool use_inv_jacobian_ = false;
};
}  // namespace moveit_servo