gazebo_ros_controller_manager.cpp

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/*
 * Copyright (c) 2008, Willow Garage, Inc.
 * All rights reserved.
 *
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 * 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.
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 *     * Neither the name of the Willow Garage, Inc. 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"
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#include <fstream>
#include <iostream>
#include <math.h>
#include <unistd.h>
#include <set>

#include <map>

#include <angles/angles.h>
#include <urdf/model.h>

//#include <gazebo/XMLConfig.hh>
//#include "physics/physics.h"
#include <gazebo/physics/physics.hh>
#include <gazebo/sensors/sensors.hh>
#include <gazebo/common/common.hh>
#include <sdf/sdf.hh>
#include <sdf/Param.hh>

#include "pr2_gazebo_plugins/gazebo_ros_controller_manager.h"

namespace gazebo {

GazeboRosControllerManager::GazeboRosControllerManager()
{
}

bool setModelsJointsStates(pr2_gazebo_plugins::SetModelsJointsStates::Request &req,
                           pr2_gazebo_plugins::SetModelsJointsStates::Response &res)
{

  return true;
}


GazeboRosControllerManager::~GazeboRosControllerManager()
{
  ROS_DEBUG("Calling FiniChild in GazeboRosControllerManager");

  //pr2_hardware_interface::ActuatorMap::const_iterator it;
  //for (it = hw_.actuators_.begin(); it != hw_.actuators_.end(); ++it)
  //  delete it->second; // why is this causing double free corrpution?
  this->cm_->~ControllerManager();
  this->rosnode_->shutdown();
#ifdef USE_CBQ
  this->controller_manager_queue_.clear();
  this->controller_manager_queue_.disable();
  this->controller_manager_callback_queue_thread_.join();
#endif
  this->ros_spinner_thread_.join();




  delete this->cm_; 
  delete this->rosnode_;

  if (this->fake_state_)
  {
    // why does this cause double free corrpution in destruction of RobotState?
    //this->fake_state_->~RobotState();
    delete this->fake_state_;
  }
}

void GazeboRosControllerManager::Load(physics::ModelPtr _parent, sdf::ElementPtr _sdf)
{
  // Get then name of the parent model
  std::string modelName = _sdf->GetParent()->Get<std::string>("name");

  // Get the world name.
  this->world = _parent->GetWorld();

  // Get a pointer to the model
  this->parent_model_ = _parent;

  // Error message if the model couldn't be found
  if (!this->parent_model_)
    gzerr << "Unable to get parent model\n";

  // Listen to the update event. This event is broadcast every
  // simulation iteration.
  this->updateConnection = event::Events::ConnectWorldUpdateBegin(
      boost::bind(&GazeboRosControllerManager::UpdateChild, this));
  gzdbg << "plugin model name: " << modelName << "\n";




  if (getenv("CHECK_SPEEDUP"))
  {
    wall_start_ = this->world->GetRealTime().Double();
    sim_start_  = this->world->GetSimTime().Double();
  }

  // check update rate against world physics update rate
  // should be equal or higher to guarantee the wrench applied is not "diluted"
  //if (this->updatePeriod > 0 &&
  //    (this->world->GetPhysicsEngine()->GetUpdateRate() > 1.0/this->updatePeriod))
  //  ROS_ERROR("gazebo_ros_force controller update rate is less than physics update rate, wrench applied will be diluted (applied intermittently)");





  // get parameter name
  this->robotNamespace = "";
  if (_sdf->HasElement("robotNamespace"))
    this->robotNamespace = _sdf->Get<std::string>("robotNamespace");

  this->robotParam = "robot_description";
  if (_sdf->HasElement("robotParam"))
    this->robotParam = _sdf->Get<std::string>("robotParam");

  this->robotParam = this->robotNamespace+"/" + this->robotParam;

  if (!ros::isInitialized())
  {
    int argc = 0;
    char** argv = NULL;
    ros::init(argc,argv,"gazebo",ros::init_options::NoSigintHandler|ros::init_options::AnonymousName);
  }
  this->rosnode_ = new ros::NodeHandle(this->robotNamespace);
  ROS_INFO("starting gazebo_ros_controller_manager plugin in ns: %s",this->robotNamespace.c_str());

  // pr2_etherCAT calls ros::spin(), we'll thread out one spinner here to mimic that
  this->ros_spinner_thread_ = boost::thread( boost::bind( &GazeboRosControllerManager::ControllerManagerROSThread,this ) );


  // load a controller manager
  this->cm_ = new pr2_controller_manager::ControllerManager(&hw_,*this->rosnode_);
  this->hw_.current_time_ = ros::Time(this->world->GetSimTime().Double());
  if (this->hw_.current_time_ < ros::Time(0.001)) this->hw_.current_time_ == ros::Time(0.001); // hardcoded to minimum of 1ms on start up

  this->rosnode_->param("gazebo/start_robot_calibrated",this->fake_calibration_,true);

  // read pr2 urdf
  // setup actuators, then setup mechanism control node
  ReadPr2Xml();

  // Initializes the fake state (for running the transmissions backwards).
  this->fake_state_ = new pr2_mechanism_model::RobotState(&this->cm_->model_);

  // The gazebo joints and mechanism joints should match up.
  if (this->cm_->state_ != NULL) // could be NULL if ReadPr2Xml is unsuccessful
  {
    for (unsigned int i = 0; i < this->cm_->state_->joint_states_.size(); ++i)
    {
      std::string joint_name = this->cm_->state_->joint_states_[i].joint_->name;

      // fill in gazebo joints pointer
      gazebo::physics::JointPtr joint = this->parent_model_->GetJoint(joint_name);
      if (joint)
      {
        this->joints_.push_back(joint);
      }
      else
      {
        //ROS_WARN("A joint named \"%s\" is not part of Mechanism Controlled joints.\n", joint_name.c_str());
        //this->joints_.push_back(NULL);  // FIXME: cannot be null, must be an empty boost shared pointer
        this->joints_.push_back(gazebo::physics::JointPtr());  // FIXME: cannot be null, must be an empty boost shared pointer
        ROS_ERROR("A joint named \"%s\" is not part of Mechanism Controlled joints.\n", joint_name.c_str());
      }

    }
  }

#ifdef USE_CBQ
  // start custom queue for controller manager
  this->controller_manager_callback_queue_thread_ = boost::thread( boost::bind( &GazeboRosControllerManager::ControllerManagerQueueThread,this ) );
#endif

}


void GazeboRosControllerManager::UpdateChild()
{
  if (this->world->IsPaused()) return;

  if (getenv("CHECK_SPEEDUP"))
  {
    double wall_elapsed = this->world->GetRealTime().Double() - wall_start_;
    double sim_elapsed  = this->world->GetSimTime().Double()  - sim_start_;
    std::cout << " real time: " <<  wall_elapsed
              << "  sim time: " <<  sim_elapsed
              << "  speed up: " <<  sim_elapsed / wall_elapsed
              << std::endl;
  }
  assert(this->joints_.size() == this->fake_state_->joint_states_.size());

  //--------------------------------------------------
  //  Pushes out simulation state
  //--------------------------------------------------

  //ROS_ERROR("joints_.size()[%d]",(int)this->joints_.size());
  // Copies the state from the gazebo joints into the mechanism joints.
  for (unsigned int i = 0; i < this->joints_.size(); ++i)
  {
    if (!this->joints_[i])
      continue;

    this->fake_state_->joint_states_[i].measured_effort_ = this->fake_state_->joint_states_[i].commanded_effort_;

    if (this->joints_[i]->HasType(gazebo::physics::Base::HINGE_JOINT))
    {
      gazebo::physics::JointPtr hj = this->joints_[i];
      this->fake_state_->joint_states_[i].position_ = this->fake_state_->joint_states_[i].position_ +
                    angles::shortest_angular_distance(this->fake_state_->joint_states_[i].position_,hj->GetAngle(0).Radian());
      this->fake_state_->joint_states_[i].velocity_ = hj->GetVelocity(0);
      //if (this->joints_[i]->GetName() == "torso_lift_motor_screw_joint")
      //  ROS_WARN("joint[%s] [%f]",this->joints_[i]->GetName().c_str(), this->fake_state_->joint_states_[i].position_);
    }
    else if (this->joints_[i]->HasType(gazebo::physics::Base::SLIDER_JOINT))
    {
      gazebo::physics::JointPtr sj = this->joints_[i];
      {
        this->fake_state_->joint_states_[i].position_ = sj->GetAngle(0).Radian();
        this->fake_state_->joint_states_[i].velocity_ = sj->GetVelocity(0);
      }
      //ROS_ERROR("joint[%s] is a slider [%f]",this->joints_[i]->GetName().c_str(),sj->GetAngle(0).Radian());
      //if (this->joints_[i]->GetName() == "torso_lift_joint")
      //  ROS_WARN("joint[%s] [%f]",this->joints_[i]->GetName().c_str(), this->fake_state_->joint_states_[i].position_);
    }
    else
    {
      /*
      ROS_WARN("joint[%s] is not hinge [%d] nor slider",this->joints_[i]->GetName().c_str(),
        (unsigned int)gazebo::physics::Base::HINGE_JOINT
        );
      for (unsigned int j = 0; j < this->joints_[i]->GetTypeCount(); j++)
      {
        ROS_WARN("  types: %d hinge[%d] slider[%d]",(unsigned int)this->joints_[i]->GetType(j),(unsigned int)this->joints_[i]->HasType(gazebo::physics::Base::HINGE_JOINT),(unsigned int)this->joints_[i]->HasType(gazebo::physics::Base::SLIDER_JOINT));
      }
      */
    }
  }

  // Reverses the transmissions to propagate the joint position into the actuators.
  this->fake_state_->propagateJointPositionToActuatorPosition();

  //--------------------------------------------------
  //  Runs Mechanism Control
  //--------------------------------------------------
  this->hw_.current_time_ = ros::Time(this->world->GetSimTime().Double());
  try
  {
    if (this->cm_->state_ != NULL) // could be NULL if ReadPr2Xml is unsuccessful
      this->cm_->update();
  }
  catch (const char* c)
  {
    if (strcmp(c,"dividebyzero")==0)
      ROS_WARN("pid controller reports divide by zero error");
    else
      ROS_WARN("unknown const char* exception: %s", c);
  }

  //--------------------------------------------------
  //  Takes in actuation commands
  //--------------------------------------------------

  // Reverses the transmissions to propagate the actuator commands into the joints.
  this->fake_state_->propagateActuatorEffortToJointEffort();

  // Copies the commands from the mechanism joints into the gazebo joints.
  for (unsigned int i = 0; i < this->joints_.size(); ++i)
  {
    if (!this->joints_[i])
      continue;

    double effort = this->fake_state_->joint_states_[i].commanded_effort_;

    double damping_coef = 0;
    if (this->cm_->state_ != NULL) // could be NULL if ReadPr2Xml is unsuccessful
    {
      if (this->cm_->state_->joint_states_[i].joint_->dynamics)
        damping_coef = this->cm_->state_->joint_states_[i].joint_->dynamics->damping;
    }

    if (this->joints_[i]->HasType(gazebo::physics::Base::HINGE_JOINT))
    {
      gazebo::physics::JointPtr hj = this->joints_[i];
      double current_velocity = hj->GetVelocity(0);
      double damping_force = damping_coef * current_velocity;
      double effort_command = effort - damping_force;
      hj->SetForce(0,effort_command);
      //if (this->joints_[i]->GetName() == "torso_lift_motor_screw_joint")
      //  ROS_ERROR("gazebo [%s] command [%f] damping [%f]",this->joints_[i]->GetName().c_str(), effort, damping_force);
    }
    else if (this->joints_[i]->HasType(gazebo::physics::Base::SLIDER_JOINT))
    {
      gazebo::physics::JointPtr sj = this->joints_[i];
      double current_velocity = sj->GetVelocity(0);
      double damping_force = damping_coef * current_velocity;
      double effort_command = effort-damping_force;
      sj->SetForce(0,effort_command);
      //if (this->joints_[i]->GetName() == "torso_lift_joint")
      //  ROS_ERROR("gazebo [%s] command [%f] damping [%f]",this->joints_[i]->GetName().c_str(), effort, damping_force);
    }
  }
}


void GazeboRosControllerManager::ReadPr2Xml()
{

  std::string urdf_param_name;
  std::string urdf_string;
  // search and wait for robot_description on param server
  while(urdf_string.empty())
  {
    ROS_INFO("gazebo controller manager plugin is waiting for urdf: %s on the param server.  (make sure there is a rosparam by that name in the ros parameter server, otherwise, this plugin blocks simulation forever).", this->robotParam.c_str());
    if (this->rosnode_->searchParam(this->robotParam,urdf_param_name))
    {
      this->rosnode_->getParam(urdf_param_name,urdf_string);
      ROS_DEBUG("found upstream\n%s\n------\n%s\n------\n%s",this->robotParam.c_str(),urdf_param_name.c_str(),urdf_string.c_str());
    }
    else
    {
      this->rosnode_->getParam(this->robotParam,urdf_string);
      ROS_DEBUG("found in node namespace\n%s\n------\n%s\n------\n%s",this->robotParam.c_str(),urdf_param_name.c_str(),urdf_string.c_str());
    }
    usleep(100000);
  }
  ROS_INFO("gazebo controller manager got pr2.xml from param server, parsing it...");

  // initialize TiXmlDocument doc with a string
  TiXmlDocument doc;
  if (!doc.Parse(urdf_string.c_str()) && doc.Error())
  {
    ROS_ERROR("Could not load the gazebo controller manager plugin's configuration file: %s\n",
            urdf_string.c_str());
  }
  else
  {
    //doc.Print();
    //std::cout << *(doc.RootElement()) << std::endl;

    // Pulls out the list of actuators used in the robot configuration.
    struct GetActuators : public TiXmlVisitor
    {
      std::set<std::string> actuators;
      virtual bool VisitEnter(const TiXmlElement &elt, const TiXmlAttribute *)
      {
        if (elt.ValueStr() == std::string("actuator") && elt.Attribute("name"))
          actuators.insert(elt.Attribute("name"));
        else if (elt.ValueStr() == std::string("rightActuator") && elt.Attribute("name"))
          actuators.insert(elt.Attribute("name"));
        else if (elt.ValueStr() == std::string("leftActuator") && elt.Attribute("name"))
          actuators.insert(elt.Attribute("name"));
        return true;
      }
    } get_actuators;
    doc.RootElement()->Accept(&get_actuators);

    // Places the found actuators into the hardware interface.
    std::set<std::string>::iterator it;
    for (it = get_actuators.actuators.begin(); it != get_actuators.actuators.end(); ++it)
    {
      //std::cout << " adding actuator " << (*it) << std::endl;
      pr2_hardware_interface::Actuator* pr2_actuator = new pr2_hardware_interface::Actuator(*it);
      pr2_actuator->state_.is_enabled_ = true;
      this->hw_.addActuator(pr2_actuator);
    }

    // Setup mechanism control node
    this->cm_->initXml(doc.RootElement());

    for (unsigned int i = 0; i < this->cm_->state_->joint_states_.size(); ++i)
      this->cm_->state_->joint_states_[i].calibrated_ = fake_calibration_;
  }
}

#ifdef USE_CBQ

// custom callback queue
void GazeboRosControllerManager::ControllerManagerQueueThread()
{
  ROS_INFO_STREAM("Callback thread id=" << boost::this_thread::get_id());

  static const double timeout = 0.01;

  while (this->rosnode_->ok())
  {
    this->controller_manager_queue_.callAvailable(ros::WallDuration(timeout));
  }
}
#endif

void GazeboRosControllerManager::ControllerManagerROSThread()
{
  ROS_INFO_STREAM("Callback thread id=" << boost::this_thread::get_id());

  //ros::Rate rate(1000);

  while (this->rosnode_->ok())
  {
    //rate.sleep(); // using rosrate gets stuck on model delete
    usleep(1000);
    ros::spinOnce();
  }
}
  // Register this plugin with the simulator
  GZ_REGISTER_MODEL_PLUGIN(GazeboRosControllerManager)
} // namespace gazebo