dynamixel_controllers: joint_torque_controller_dual

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00001 # -*- coding: utf-8 -*-
00002 #
00003 # Software License Agreement (BSD License)
00004 #
00005 # Copyright (c) 2010-2011, Antons Rebguns.
00006 # All rights reserved.
00007 #
00008 # Redistribution and use in source and binary forms, with or without
00009 # modification, are permitted provided that the following conditions
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00011 #
00012 #  * Redistributions of source code must retain the above copyright
00013 #    notice, this list of conditions and the following disclaimer.
00014 #  * Redistributions in binary form must reproduce the above
00015 #    copyright notice, this list of conditions and the following
00016 #    disclaimer in the documentation and/or other materials provided
00017 #    with the distribution.
00018 #  * Neither the name of University of Arizona nor the names of its
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00022 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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00027 # INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
00028 # BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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00030 # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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00034 
00035 from __future__ import division
00036 
00037 
00038 __author__ = 'Antons Rebguns'
00039 __copyright__ = 'Copyright (c) 2010-2011 Antons Rebguns'
00040 
00041 __license__ = 'BSD'
00042 __maintainer__ = 'Antons Rebguns'
00043 __email__ = 'anton@email.arizona.edu'
00044 
00045 
00046 import rospy
00047 
00048 from dynamixel_driver.dynamixel_const import *
00049 from dynamixel_controllers.joint_controller import JointController
00050 
00051 from dynamixel_msgs.msg import JointState
00052 
00053 class JointTorqueControllerDualMotor(JointController):
00054     def __init__(self, dxl_io, controller_namespace, port_namespace):
00055         JointController.__init__(self, dxl_io, controller_namespace, port_namespace)
00056         
00057         self.master_id = rospy.get_param(self.controller_namespace + '/motor_master/id')
00058         self.master_initial_position_raw = rospy.get_param(self.controller_namespace + '/motor_master/init')
00059         self.master_min_angle_raw = rospy.get_param(self.controller_namespace + '/motor_master/min')
00060         self.master_max_angle_raw = rospy.get_param(self.controller_namespace + '/motor_master/max')
00061         
00062         self.slave_id = rospy.get_param(self.controller_namespace + '/motor_slave/id')
00063         
00064         self.flipped = self.master_min_angle_raw > self.master_max_angle_raw
00065         self.last_commanded_torque = 0.0
00066         
00067         self.joint_state = JointState(name=self.joint_name, motor_ids=[self.master_id, self.slave_id])
00068 
00069 
00070     def initialize(self):
00071         # verify that the expected motor is connected and responding
00072         available_ids = rospy.get_param('dynamixel/%s/connected_ids' % self.port_namespace, [])
00073         if not (self.master_id in available_ids and
00074                 self.slave_id in available_ids):
00075             rospy.logwarn('The specified motor id is not connected and responding.')
00076             rospy.logwarn('Available ids: %s' % str(available_ids))
00077             rospy.logwarn('Specified ids: %d %d' % (self.master_id, self.slave_id))
00078             return False
00079             
00080         self.RADIANS_PER_ENCODER_TICK = rospy.get_param('dynamixel/%s/%d/radians_per_encoder_tick' % (self.port_namespace, self.master_id))
00081         self.ENCODER_TICKS_PER_RADIAN = rospy.get_param('dynamixel/%s/%d/encoder_ticks_per_radian' % (self.port_namespace, self.master_id))
00082         
00083         if self.flipped:
00084             self.master_min_angle = (self.master_initial_position_raw - self.master_min_angle_raw) * self.RADIANS_PER_ENCODER_TICK
00085             self.master_max_angle = (self.master_initial_position_raw - self.master_max_angle_raw) * self.RADIANS_PER_ENCODER_TICK
00086         else:
00087             self.master_min_angle = (self.master_min_angle_raw - self.master_initial_position_raw) * self.RADIANS_PER_ENCODER_TICK
00088             self.master_max_angle = (self.master_max_angle_raw - self.master_initial_position_raw) * self.RADIANS_PER_ENCODER_TICK
00089             
00090         self.ENCODER_RESOLUTION = rospy.get_param('dynamixel/%s/%d/encoder_resolution' % (self.port_namespace, self.master_id))
00091         self.MAX_POSITION = self.ENCODER_RESOLUTION - 1
00092         self.VELOCITY_PER_TICK = rospy.get_param('dynamixel/%s/%d/radians_second_per_encoder_tick' % (self.port_namespace, self.master_id))
00093         self.MAX_VELOCITY = rospy.get_param('dynamixel/%s/%d/max_velocity' % (self.port_namespace, self.master_id))
00094         self.MIN_VELOCITY = self.VELOCITY_PER_TICK
00095         
00096         if self.compliance_slope is not None: self.set_compliance_slope(self.compliance_slope)
00097         if self.compliance_margin is not None: self.set_compliance_margin(self.compliance_margin)
00098         if self.compliance_punch is not None: self.set_compliance_punch(self.compliance_punch)
00099         if self.torque_limit is not None: self.set_torque_limit(self.torque_limit)
00100         
00101         self.joint_max_speed = rospy.get_param(self.controller_namespace + '/joint_max_speed', self.MAX_VELOCITY)
00102         
00103         if self.joint_max_speed < self.MIN_VELOCITY: self.joint_max_speed = self.MIN_VELOCITY
00104         elif self.joint_max_speed > self.MAX_VELOCITY: self.joint_max_speed = self.MAX_VELOCITY
00105         
00106         if self.joint_speed < self.MIN_VELOCITY: self.joint_speed = self.MIN_VELOCITY
00107         elif self.joint_speed > self.joint_max_speed: self.joint_speed = self.joint_max_speed
00108         
00109         self.set_speed(0.0)
00110         
00111         return True
00112 
00113 
00114     def set_torque_enable(self, torque_enable):
00115         mcv_master = (self.master_id, torque_enable)
00116         mcv_slave = (self.slave_id, torque_enable)
00117         self.dxl_io.set_multi_torque_enabled([mcv_master, mcv_slave])
00118 
00119 
00120     def set_speed(self, speed):
00121         if speed < -self.joint_max_speed: speed = -self.joint_max_speed
00122         elif speed > self.joint_max_speed: speed = self.joint_max_speed
00123         self.last_commanded_torque = speed
00124         speed_raw = int(round(speed / self.VELOCITY_PER_TICK))
00125         mcv_master = (self.master_id, speed_raw)
00126         mcv_slave = (self.slave_id, -mcv_master[1])
00127         self.dxl_io.set_multi_speed([mcv_master, mcv_slave])
00128 
00129 
00130     def set_compliance_slope(self, slope):
00131         if slope < DXL_MIN_COMPLIANCE_SLOPE: slope = DXL_MIN_COMPLIANCE_SLOPE
00132         elif slope > DXL_MAX_COMPLIANCE_SLOPE: slope = DXL_MAX_COMPLIANCE_SLOPE
00133         mcv_master = (self.master_id, slope, slope)
00134         mcv_slave = (self.slave_id, slope, slope)
00135         self.dxl_io.set_multi_compliance_slopes([mcv_master, mcv_slave])
00136 
00137 
00138     def set_compliance_margin(self, margin):
00139         if margin < DXL_MIN_COMPLIANCE_MARGIN: margin = DXL_MIN_COMPLIANCE_MARGIN
00140         elif margin > DXL_MAX_COMPLIANCE_MARGIN: margin = DXL_MAX_COMPLIANCE_MARGIN
00141         else: margin = int(margin)
00142         mcv_master = (self.master_id, margin, margin)
00143         mcv_slave = (self.slave_id, margin, margin)
00144         self.dxl_io.set_multi_compliance_margins([mcv_master, mcv_slave])
00145 
00146 
00147     def set_compliance_punch(self, punch):
00148         if punch < DXL_MIN_PUNCH: punch = DXL_MIN_PUNCH
00149         elif punch > DXL_MAX_PUNCH: punch = DXL_MAX_PUNCH
00150         else: punch = int(punch)
00151         mcv_master = (self.master_id, punch)
00152         mcv_slave = (self.slave_id, punch)
00153         self.dxl_io.set_multi_punch([mcv_master, mcv_slave])
00154 
00155 
00156     def set_torque_limit(self, max_torque):
00157         if max_torque > 1: max_torque = 1.0
00158         elif max_torque < 0: max_torque = 0.0     # turn off motor torque
00159         raw_torque_val = int(DXL_MAX_TORQUE_TICK * max_torque)
00160         mcv_master = (self.master_id, raw_torque_val)
00161         mcv_slave = (self.slave_id, raw_torque_val)
00162         self.dxl_io.set_multi_torque_limit([mcv_master, mcv_slave])
00163 
00164 
00165     def process_motor_states(self, state_list):
00166         if self.running:
00167             states = {}
00168             
00169             for state in state_list.motor_states:
00170                 if state.id in [self.master_id, self.slave_id]: states[state.id] = state
00171                 
00172             if states:
00173                 state = states[self.master_id]
00174                 self.joint_state.motor_temps = [state.temperature, states[self.slave_id].temperature]
00175                 self.joint_state.goal_pos = self.last_commanded_torque
00176                 self.joint_state.current_pos = self.raw_to_rad(state.position, self.master_initial_position_raw, self.flipped, self.RADIANS_PER_ENCODER_TICK)
00177                 self.joint_state.error = 0.0
00178                 self.joint_state.velocity = state.speed * self.VELOCITY_PER_TICK
00179                 self.joint_state.load = state.load
00180                 self.joint_state.is_moving = state.moving
00181                 self.joint_state.header.stamp = rospy.Time.from_sec(state.timestamp)
00182                 
00183                 self.joint_state_pub.publish(self.joint_state)
00184 
00185 
00186     def process_command(self, msg):
00187         self.set_speed(msg.data)
00188