Stiffness control API

NAOqi Motion - Overview | API

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Method list

class ALMotionProxy

• ALMotionProxy::wakeUp
• ALMotionProxy::rest
• ALMotionProxy::robotIsWakeUp
• ALMotionProxy::stiffnessInterpolation
• ALMotionProxy::setStiffnesses
• ALMotionProxy::getStiffnesses

Event list

• robotIsWakeUp()
• ALMotion/Stiffness/wakeUpStarted()
• ALMotion/Stiffness/wakeUpFinished()
• ALMotion/Protection/DisabledDevicesChanged()

Methods

bool ALMotionProxy::wakeUp()

Returns:True if the call succeeded, False otherwise.

The robot wakes up: sets Motor on and, if needed, goes to initial position. If the robot is already stiffened, the call returns True immediately.

almotion_wakeUp.py

#! /usr/bin/env python
# -*- encoding: UTF-8 -*-

"""Example: Use wakeUp Method"""

import qi
import argparse
import sys
import time


def main(session):
    """
    This example uses the wakeUp method.
    """
    # Get the service ALMotion.

    motion_service  = session.service("ALMotion")

    motion_service.wakeUp()

    # print motion state
    print motion_service.getSummary()
    time.sleep(4.0)

    # Go to rest position
    motion_service.rest()


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", type=str, default="127.0.0.1",
                        help="Robot IP address. On robot or Local Naoqi: use '127.0.0.1'.")
    parser.add_argument("--port", type=int, default=9559,
                        help="Naoqi port number")

    args = parser.parse_args()
    session = qi.Session()
    try:
        session.connect("tcp://" + args.ip + ":" + str(args.port))
    except RuntimeError:
        print ("Can't connect to Naoqi at ip \"" + args.ip + "\" on port " + str(args.port) +".\n"
               "Please check your script arguments. Run with -h option for help.")
        sys.exit(1)
    main(session)

void ALMotionProxy::rest()

The robot rests: goes to a relaxed and safe position and sets Motor off. For example, H25 or H21 goes to the Crouch posture and sets the Stiffness off.

almotion_rest.py

#! /usr/bin/env python
# -*- encoding: UTF-8 -*-

"""Example: Use rest Method"""

import qi
import argparse
import sys


def main(session):
    """
    This example uses the rest method.
    """
    # Get the services ALMotion & ALRobotPosture.

    motion_service  = session.service("ALMotion")
    posture_service = session.service("ALRobotPosture")

    # Wake up robot
    motion_service.wakeUp()

    # Send robot to Pose Init
    posture_service.goToPosture("StandInit", 0.5)

    # Go to rest position
    motion_service.rest()

    # print motion state
    print motion_service.getSummary()


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", type=str, default="127.0.0.1",
                        help="Robot IP address. On robot or Local Naoqi: use '127.0.0.1'.")
    parser.add_argument("--port", type=int, default=9559,
                        help="Naoqi port number")

    args = parser.parse_args()
    session = qi.Session()
    try:
        session.connect("tcp://" + args.ip + ":" + str(args.port))
    except RuntimeError:
        print ("Can't connect to Naoqi at ip \"" + args.ip + "\" on port " + str(args.port) +".\n"
               "Please check your script arguments. Run with -h option for help.")
        sys.exit(1)
    main(session)

bool ALMotionProxy::robotIsWakeUp()

Returns:True if the robot is awake.

void ALMotionProxy::stiffnessInterpolation(const AL::ALValue& names, const AL::ALValue& stiffnessLists, const AL::ALValue& timeLists)

Interpolates one or multiple joints to a targeted stiffness or along timed trajectories of stiffness. This is a blocking call.

Parameters:

• names – Name or names of joints, chains, “Body”, “JointActuators”, “Joints” or “Actuators”.
• stiffnessLists – An stiffness, list of stiffnesses or list of list of stiffnesses
• timeLists – A time, list of times or list of list of times.

almotion_stiffnessInterpolation.py

#! /usr/bin/env python
# -*- encoding: UTF-8 -*-

"""Example: Use stiffnessInterpolation Method"""

import qi
import argparse
import sys
import time


def main(session):
    """
    This example uses the stiffnessInterpolation method.
    """
    # Get the service ALMotion.

    motion_service  = session.service("ALMotion")
    motion_service.wakeUp()

    # Example showing how to interpolate to minimum stiffness in 1 second
    names  = 'LArm'
    stiffnessLists  = 0.0
    timeLists  = 1.0
    motion_service.stiffnessInterpolation(names, stiffnessLists, timeLists)

    time.sleep(1.0)

    # Example showing a stiffness trajectory for a single joint
    names  = ['LWristYaw']
    stiffnessLists  = [0.25, 0.5, 1.0, 0.0]
    timeLists  = [1.0, 2.0, 3.0, 4.0]
    motion_service.stiffnessInterpolation(names, stiffnessLists, timeLists)

    motion_service.rest()

if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", type=str, default="127.0.0.1",
                        help="Robot IP address. On robot or Local Naoqi: use '127.0.0.1'.")
    parser.add_argument("--port", type=int, default=9559,
                        help="Naoqi port number")

    args = parser.parse_args()
    session = qi.Session()
    try:
        session.connect("tcp://" + args.ip + ":" + str(args.port))
    except RuntimeError:
        print ("Can't connect to Naoqi at ip \"" + args.ip + "\" on port " + str(args.port) +".\n"
               "Please check your script arguments. Run with -h option for help.")
        sys.exit(1)
    main(session)

void ALMotionProxy::setStiffnesses(const AL::ALValue& names, const AL::ALValue& stiffnesses)

Sets the stiffness of one or more joints. This is a non-blocking call.

Parameters:

• names – Names of joints, chains, “Body”, “JointActuators”, “Joints” or “Actuators”.
• stiffnesses – One or more stiffnesses between zero and one.

almotion_setstiffnesses.cpp

#include <iostream>
#include <alproxies/almotionproxy.h>

int main(int argc, char **argv)
{
  std::string robotIp = "127.0.0.1";

  if (argc < 2) {
    std::cerr << "Usage: almotion_setstiffnesses robotIp "
              << "(optional default \"127.0.0.1\")."<< std::endl;
  }
  else {
    robotIp = argv[1];
  }

  AL::ALMotionProxy motion(robotIp);

  // Example showing how to set the stiffness to 1.0.
  // Beware, doing this could be dangerous, it is safer to use the
  // stiffnessInterpolation method which takes a duration parameter.
  std::string names  = "Body";
  // If only one parameter is received, this is applied to all joints
  float stiffnesses  = 1.0f;
  motion.setStiffnesses(names, stiffnesses);

  return 0;
}

almotion_setStiffnesses.py

#! /usr/bin/env python
# -*- encoding: UTF-8 -*-

"""Example: Use setStiffnesses Method"""

import qi
import argparse
import sys


def main(session):
    """
    This example uses the setStiffnesses method.
    """
    # Get the service ALMotion.

    motion_service  = session.service("ALMotion")

    # Example showing how to set the stiffness to 1.0.
    # Beware, doing this could be dangerous, it is safer to use the
    #   stiffnessInterpolation method which takes a duration parameter.
    names  = 'Head'
    # If only one parameter is received, this is applied to all joints
    stiffnesses  = 1.0
    motion_service.setStiffnesses(names, stiffnesses)


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", type=str, default="127.0.0.1",
                        help="Robot IP address. On robot or Local Naoqi: use '127.0.0.1'.")
    parser.add_argument("--port", type=int, default=9559,
                        help="Naoqi port number")

    args = parser.parse_args()
    session = qi.Session()
    try:
        session.connect("tcp://" + args.ip + ":" + str(args.port))
    except RuntimeError:
        print ("Can't connect to Naoqi at ip \"" + args.ip + "\" on port " + str(args.port) +".\n"
               "Please check your script arguments. Run with -h option for help.")
        sys.exit(1)
    main(session)

std::vector<float> ALMotionProxy::getStiffnesses(const AL::ALValue& jointName)

Gets stiffness of a joint or group of joints

Parameters:

• jointName – Name of the joints, chains, “Body”, “JointActuators”, “Joints” or “Actuators”.

Returns:

One or more stiffnesses. 1.0 indicates maximum stiffness. 0.0 indicated minimum stiffness

almotion_getstiffnesses.cpp

#include <iostream>
#include <alproxies/almotionproxy.h>

int main(int argc, char **argv)
{
  std::string robotIp = "127.0.0.1";

  if (argc < 2) {
    std::cerr << "Usage: almotion_getstiffnesses robotIp "
              << "(optional default \"127.0.0.1\")."<< std::endl;
  }
  else {
    robotIp = argv[1];
  }

  AL::ALMotionProxy motion(robotIp);

  // Example showing how to get the Body stiffnesses
  std::string jointName = "Body";
  std::vector<float> stiffnesses = motion.getStiffnesses(jointName);

  std::cout << jointName << "stiffnesses: " << stiffnesses << std::endl;

  return 0;
}

almotion_getStiffnesses.py

#! /usr/bin/env python
# -*- encoding: UTF-8 -*-

"""Example: Use getStiffnesses Method"""

import qi
import argparse
import sys


def main(session):
    """
    This example uses the getStiffnesses method.
    """
    # Get the service ALMotion.

    motion_service  = session.service("ALMotion")

    # Example showing how to get the Body stiffnesses
    jointName   = "Body"
    stiffnesses = motion_service.getStiffnesses(jointName)
    print "Body Stiffnesses:"
    print stiffnesses


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--ip", type=str, default="127.0.0.1",
                        help="Robot IP address. On robot or Local Naoqi: use '127.0.0.1'.")
    parser.add_argument("--port", type=int, default=9559,
                        help="Naoqi port number")

    args = parser.parse_args()
    session = qi.Session()
    try:
        session.connect("tcp://" + args.ip + ":" + str(args.port))
    except RuntimeError:
        print ("Can't connect to Naoqi at ip \"" + args.ip + "\" on port " + str(args.port) +".\n"
               "Please check your script arguments. Run with -h option for help.")
        sys.exit(1)
    main(session)

Events

Event: "robotIsWakeUp"

callback(std::string eventName, bool val, std::string subscriberIdentifier)

Raised when the awake status of the robot changes.

Parameters:

• eventName (std::string) – “robotIsWakeUp”
• val – True if the robot is awake. False if the robot is not awake.
• subscriberIdentifier (std::string) –

Event: "ALMotion/Stiffness/wakeUpStarted"

callback(std::string eventName, bool val, std::string subscriberIdentifier)

Raised at ALMotionProxy::wakeUp start.

Parameters:

• eventName (std::string) – “ALMotion/Stiffness/wakeUpStarted”
• val – always True.
• subscriberIdentifier (std::string) –

Event: "ALMotion/Stiffness/wakeUpFinished"

callback(std::string eventName, bool val, std::string subscriberIdentifier)

Raised at ALMotionProxy::wakeUp finish.

Parameters:

• eventName (std::string) – “ALMotion/Stiffness/wakeUpFinished”
• val – always True.
• subscriberIdentifier (std::string) –

Event: "ALMotion/Protection/DisabledDevicesChanged"

callback(std::string eventName, AL::ALValue val, std::string subscriberIdentifier)

Raised when devices availability changed. When a device is not available the stiffness and movement on this device are prohibited.

The ALValue format is: [[std::string deviceName, bool disabled],...] deviceName could be a chainName or “Body”. In “Body” case ( [[“Body”, true]] ) ALMotionProxy::wakeUp is prohibited.

Parameters:

• eventName (std::string) – “ALMotion/Protection/DisabledDevicesChanged”
• val –

  An ALValue with the actual disabled devices status.

  Example: [[“LArm”, true]], [“Head”, false]]

• subscriberIdentifier (std::string) –