generate_elbow_motion.cpp

An example showing how to move the robot's elbow.

Warning

Before executing this example, make sure that the elbow has enough space to move.

// Copyright (c) 2017 Franka Emika GmbH
// Use of this source code is governed by the Apache-2.0 license, see LICENSE
#include <cmath>
#include <iostream>

#include <franka/exception.h>
#include <franka/robot.h>

#include "examples_common.h"

int main(int argc, char** argv) {
  if (argc != 2) {
    std::cerr << "Usage: " << argv[0] << " <robot-hostname>" << std::endl;
    return -1;
  }
  try {
    franka::Robot robot(argv[1]);
    setDefaultBehavior(robot);

    // First move the robot to a suitable joint configuration
    std::array<double, 7> q_goal = {{0, -M_PI_4, 0, -3 * M_PI_4, 0, M_PI_2, M_PI_4}};
    MotionGenerator motion_generator(0.5, q_goal);
    std::cout << "WARNING: This example will move the robot! "
              << "Please make sure to have the user stop button at hand!" << std::endl
              << "Press Enter to continue..." << std::endl;
    std::cin.ignore();
    robot.control(motion_generator);
    std::cout << "Finished moving to initial joint configuration." << std::endl;

    // Set additional parameters always before the control loop, NEVER in the control loop!
    // Set collision behavior.
    robot.setCollisionBehavior(
        {{20.0, 20.0, 18.0, 18.0, 16.0, 14.0, 12.0}}, {{20.0, 20.0, 18.0, 18.0, 16.0, 14.0, 12.0}},
        {{20.0, 20.0, 18.0, 18.0, 16.0, 14.0, 12.0}}, {{20.0, 20.0, 18.0, 18.0, 16.0, 14.0, 12.0}},
        {{20.0, 20.0, 20.0, 25.0, 25.0, 25.0}}, {{20.0, 20.0, 20.0, 25.0, 25.0, 25.0}},
        {{20.0, 20.0, 20.0, 25.0, 25.0, 25.0}}, {{20.0, 20.0, 20.0, 25.0, 25.0, 25.0}});

    std::array<double, 16> initial_pose;
    std::array<double, 2> initial_elbow;
    double time = 0.0;
    robot.control(
        [&time, &initial_pose, &initial_elbow](const franka::RobotState& robot_state,
                                               franka::Duration period) -> franka::CartesianPose {
          time += period.toSec();

          if (time == 0.0) {
            initial_pose = robot_state.O_T_EE_c;
            initial_elbow = robot_state.elbow_c;
          }

          double angle = M_PI / 10.0 * (1.0 - std::cos(M_PI / 5.0 * time));

          auto elbow = initial_elbow;
          elbow[0] += angle;

          if (time >= 10.0) {
            std::cout << std::endl << "Finished motion, shutting down example" << std::endl;
            return franka::MotionFinished({initial_pose, elbow});
          }

          return {initial_pose, elbow};
        });
  } catch (const franka::Exception& e) {
    std::cout << e.what() << std::endl;
    return -1;
  }

  return 0;
}