simple_transmission_for_muscle.cpp

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/*
 * Author: Stuart Glaser
 *
 * modified by Ugo Cupcic
 */

#include "sr_mechanism_model/simple_transmission_for_muscle.hpp"
#include <string>

using ros_ethercat_model::Transmission;
using ros_ethercat_model::RobotState;
using sr_actuator::SrMuscleActuator;
using std::string;

PLUGINLIB_EXPORT_CLASS(sr_mechanism_model::SimpleTransmissionForMuscle, Transmission)

namespace sr_mechanism_model
{

  bool SimpleTransmissionForMuscle::initXml(TiXmlElement *elt, RobotState *robot)
  {
    if (!SimpleTransmission::Transmission::initXml(elt, robot))
    {
      return false;
    }

    string act_name = actuator_->name_;
    delete actuator_;  // That's a SrMotorActuator at this point
    actuator_ = new SrMuscleActuator();
    actuator_->name_ = act_name;
    actuator_->command_.enable_ = true;

    return true;
  }

  void SimpleTransmissionForMuscle::propagatePosition()
  {
    SrMuscleActuator *act = static_cast<SrMuscleActuator *>(actuator_);
    joint_->position_ = act->state_.position_;
    joint_->velocity_ = act->state_.velocity_;

    // We don't want to define a modified version of JointState, as that would imply using a modified version
    // of robot_state.hpp, controller manager, ethercat_hardware and ros_etherCAT main loop
    // So we will encode the two uint16_t that contain the data from the muscle pressure sensors
    // into the double effort_. (We don't have any measured effort in the muscle hand anyway).
    // Then in the joint controller we will decode that back into uint16_t.
    joint_->effort_ = (static_cast<double>(act->muscle_state_.pressure_[1]) * 0x10000)
                      + static_cast<double>(act->muscle_state_.pressure_[0]);
  }

  void SimpleTransmissionForMuscle::propagateEffort()
  {
    SrMuscleActuator *act = static_cast<SrMuscleActuator *>(actuator_);
    act->command_.enable_ = true;

    // We don't want to define a modified version of JointState, as that would imply using a modified version
    // of robot_state.hpp, controller manager, ethercat_hardware and ros_etherCAT main loop
    // So the controller encodes the two int16 that contain the valve commands into the double effort_.
    // (We don't have any real commanded_effort_ in the muscle hand anyway).
    // Here we decode them back into two int16_t.
    double valve_0 = fmod(joint_->commanded_effort_, 0x10);
    int8_t valve_0_tmp = (int8_t) (valve_0 + 0.5);
    if (valve_0_tmp >= 8)
    {
      valve_0_tmp -= 8;
      valve_0_tmp *= (-1);
    }

    int8_t valve_1_tmp = (int8_t) (((fmod(joint_->commanded_effort_, 0x100) - valve_0) / 0x10) + 0.5);
    if (valve_1_tmp >= 8)
    {
      valve_1_tmp -= 8;
      valve_1_tmp *= (-1);
    }

    act->muscle_command_.valve_[0] = valve_0_tmp;
    act->muscle_command_.valve_[1] = valve_1_tmp;
  }

}  // namespace sr_mechanism_model

/* For the emacs weenies in the crowd.
Local Variables:
   c-basic-offset: 2
End:
 */