scripts/wt_node.py

   1 #!/usr/bin/env python
   2 # -*- coding: iso-8859-15 -*-
   3
   4 import rospy
   5 import tf
   6 import struct
   7 import thread
   8 import prctl
   9 import spidev
  10 from time import sleep
  11 from i2c import i2c, i2c_write_reg, i2c_read_reg
  12 from math import *
  13 from geometry_msgs.msg import Twist
  14 from nav_msgs.msg import Odometry
  15 from diagnostic_msgs.msg import DiagnosticArray, DiagnosticStatus, KeyValue
  16 from dynamic_reconfigure.server import Server
  17 from sensor_msgs.msg import Imu, Range, BatteryState
  18 from wild_thumper.cfg import WildThumperConfig
  19
  20 WHEEL_DIST = 0.248
  21 BATTERY_CAPACITY_FULL = 2.750 # Ah, NiMH=2.750, LiFePO4=3.100
  22 UPDATE_RATE = 20.0
  23
  24 class WTBase:
  25         def __init__(self):
  26                 rospy.init_node('wild_thumper')
  27                 prctl.set_name("wild_thumper")
  28                 enable_odom_tf = rospy.get_param("~enable_odom_tf", True)
  29                 if enable_odom_tf:
  30                         self.tf_broadcaster = tf.broadcaster.TransformBroadcaster()
  31                 else:
  32                         self.tf_broadcaster = None
  33                 self.dyn_conf = Server(WildThumperConfig, self.execute_dyn_reconf)
  34                 self.pub_odom = rospy.Publisher("odom", Odometry, queue_size=16)
  35                 self.pub_diag = rospy.Publisher("diagnostics", DiagnosticArray, queue_size=16)
  36                 self.pub_range_fwd_left = rospy.Publisher("range_forward_left", Range, queue_size=16)
  37                 self.pub_range_fwd_right = rospy.Publisher("range_forward_right", Range, queue_size=16)
  38                 self.pub_range_bwd = rospy.Publisher("range_backward", Range, queue_size=16)
  39                 self.pub_range_left = rospy.Publisher("range_left", Range, queue_size=16)
  40                 self.pub_range_right = rospy.Publisher("range_right", Range, queue_size=16)
  41                 self.pub_battery = rospy.Publisher("battery", BatteryState, queue_size=16)
  42                 self.cmd_vel = None
  43                 self.cur_vel = (0, 0)
  44                 self.bMotorManual = False
  45                 self.set_speed(0, 0)
  46                 self.volt_last_warn = rospy.Time.now()
  47                 i2c_write_reg(0x50, 0x90, struct.pack("BB", 1, 1)) # switch direction
  48                 rospy.Subscriber("cmd_vel_out", Twist, self.cmdVelReceived)
  49                 rospy.Subscriber("imu", Imu, self.imuReceived)
  50                 self.bDocked = False
  51                 self.bDocked_last = False
  52                 self.battery_capacity = BATTERY_CAPACITY_FULL*3600 # As
  53                 rospy.loginfo("Init done")
  54                 self.run()
  55
  56         def run(self):
  57                 rate = rospy.Rate(UPDATE_RATE)
  58                 sleep(3) # wait 3s for ros to register and establish all subscriber connections before sending reset diag
  59                 reset_val = self.get_reset()
  60                 rospy.loginfo("Reset Status: 0x%x" % reset_val)
  61                 ir_count = 0
  62                 sonar_count = 0
  63                 i2c_write_reg(0x50, 0xA4, struct.pack("B", 1)) # enable Watchdog
  64                 while not rospy.is_shutdown():
  65                         rospy.logdebug("Loop alive")
  66                         #print "Watchdog", struct.unpack(">B", i2c_read_reg(0x50, 0xA4, 1))[0]
  67                         #print struct.unpack(">B", i2c_read_reg(0x50, 0xA2, 1))[0] # count test
  68                         self.get_motor_err()
  69                         self.get_odom()
  70                         self.get_power()
  71
  72                         if ir_count == 0:
  73                                 self.get_dist_left()
  74                                 ir_count+=1
  75                         else:
  76                                 self.get_dist_right()
  77                                 ir_count=0
  78
  79                         if sonar_count == 0:
  80                                 self.get_dist_forward_left()
  81                                 self.update_dist_backward()
  82                                 sonar_count+=1
  83                         elif sonar_count == 1:
  84                                 self.get_dist_backward()
  85                                 self.update_dist_forward_right()
  86                                 sonar_count+=1
  87                         elif sonar_count == 2:
  88                                 self.get_dist_forward_right()
  89                                 self.update_dist_forward_left()
  90                                 sonar_count=0
  91
  92                         if self.cmd_vel != None:
  93                                 self.set_speed(self.cmd_vel[0], self.cmd_vel[1])
  94                                 self.cur_vel = self.cmd_vel
  95                                 self.cmd_vel = None
  96
  97                         self.check_docked()
  98                         rate.sleep()
  99
 100         def execute_dyn_reconf(self, config, level):
 101                 self.bClipRangeSensor = config["range_sensor_clip"]
 102                 self.range_sensor_max = config["range_sensor_max"]
 103                 self.range_sensor_fov = config["range_sensor_fov"]
 104                 self.odom_covar_xy = config["odom_covar_xy"]
 105                 self.odom_covar_angle = config["odom_covar_angle"]
 106                 self.rollover_protect = config["rollover_protect"]
 107                 self.rollover_protect_limit = config["rollover_protect_limit"]
 108                 self.rollover_protect_pwm = config["rollover_protect_pwm"]
 109                 self.bStayDocked = config["stay_docked"]
 110
 111                 return config
 112
 113         def imuReceived(self, msg):
 114                 if self.rollover_protect and (any(self.cur_vel) or self.bMotorManual):
 115                         (roll, pitch, yaw) = tf.transformations.euler_from_quaternion(msg.orientation.__getstate__())
 116                         if pitch > self.rollover_protect_limit*pi/180:
 117                                 self.bMotorManual = True
 118                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", 0, self.rollover_protect_pwm, 0, self.rollover_protect_pwm))
 119                                 rospy.logwarn("Running forward rollver protection")
 120                         elif pitch < -self.rollover_protect_limit*pi/180:
 121                                 self.bMotorManual = True
 122                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", -self.rollover_protect_pwm, 0, -self.rollover_protect_pwm, 0))
 123                                 rospy.logwarn("Running backward rollver protection")
 124                         elif self.bMotorManual:
 125                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", 0, 0, 0, 0))
 126                                 self.bMotorManual = False
 127                                 self.cmd_vel = (0, 0)
 128                                 rospy.logwarn("Rollver protection done")
 129
 130         def get_reset(self):
 131                 reset = struct.unpack(">B", i2c_read_reg(0x50, 0xA0, 1))[0]
 132
 133                 msg = DiagnosticArray()
 134                 msg.header.stamp = rospy.Time.now()
 135                 stat = DiagnosticStatus()
 136                 stat.name = "Reset reason"
 137                 stat.level = DiagnosticStatus.ERROR if reset & 0x0c else DiagnosticStatus.OK
 138                 stat.message = "0x%02x" % reset
 139
 140                 wdrf = bool(reset & (1 << 3))
 141                 if wdrf: rospy.loginfo("Watchdog Reset")
 142                 borf = bool(reset & (1 << 2))
 143                 if borf: rospy.loginfo("Brown-out Reset Flag")
 144                 extrf = bool(reset & (1 << 1))
 145                 if extrf: rospy.loginfo("External Reset Flag")
 146                 porf = bool(reset & (1 << 0))
 147                 if porf: rospy.loginfo("Power-on Reset Flag")
 148                 stat.values.append(KeyValue("Watchdog Reset Flag", str(wdrf)))
 149                 stat.values.append(KeyValue("Brown-out Reset Flag", str(borf)))
 150                 stat.values.append(KeyValue("External Reset Flag", str(extrf)))
 151                 stat.values.append(KeyValue("Power-on Reset Flag", str(porf)))
 152
 153                 msg.status.append(stat)
 154                 self.pub_diag.publish(msg)
 155                 return reset
 156
 157
 158         def get_motor_err(self):
 159                 err = struct.unpack(">B", i2c_read_reg(0x50, 0xA1, 1))[0]
 160
 161                 msg = DiagnosticArray()
 162                 msg.header.stamp = rospy.Time.now()
 163                 stat = DiagnosticStatus()
 164                 stat.name = "Motor: Error Status"
 165                 stat.level = DiagnosticStatus.ERROR if err else DiagnosticStatus.OK
 166                 stat.message = "0x%02x" % err
 167
 168                 # Diag
 169                 stat.values.append(KeyValue("aft left diag", str(bool(err & (1 << 0)))))
 170                 stat.values.append(KeyValue("front left diag", str(bool(err & (1 << 1)))))
 171                 stat.values.append(KeyValue("aft right diag", str(bool(err & (1 << 2)))))
 172                 stat.values.append(KeyValue("front right diag", str(bool(err & (1 << 3)))))
 173                 # Stall
 174                 stat.values.append(KeyValue("aft left stall", str(bool(err & (1 << 4)))))
 175                 stat.values.append(KeyValue("front left stall", str(bool(err & (1 << 5)))))
 176                 stat.values.append(KeyValue("aft right stall", str(bool(err & (1 << 6)))))
 177                 stat.values.append(KeyValue("front right stall", str(bool(err & (1 << 7)))))
 178
 179                 msg.status.append(stat)
 180                 self.pub_diag.publish(msg)
 181
 182         def get_power(self):
 183                 volt = struct.unpack(">h", i2c_read_reg(0x52, 0x09, 2))[0]/100.0
 184                 current = struct.unpack(">h", i2c_read_reg(0x52, 0x0D, 2))[0]/1000.0
 185
 186                 msg = DiagnosticArray()
 187                 msg.header.stamp = rospy.Time.now()
 188                 stat = DiagnosticStatus()
 189                 stat.name = "Power"
 190                 stat.level = DiagnosticStatus.ERROR if volt < 7 or current > 5 else DiagnosticStatus.OK
 191                 stat.message = "%.2fV, %.2fA" % (volt, current)
 192
 193                 msg.status.append(stat)
 194                 self.pub_diag.publish(msg)
 195
 196                 if volt < 7 and (rospy.Time.now() - self.volt_last_warn).to_sec() > 10:
 197                         rospy.logerr("Voltage critical: %.2fV" % (volt))
 198                         self.volt_last_warn = rospy.Time.now()
 199
 200                 self.bDocked = volt > 10.1
 201                 self.update_capacity(volt, current)
 202
 203                 if self.pub_battery.get_num_connections() > 0:
 204                         batmsg = BatteryState()
 205                         batmsg.header.stamp = rospy.Time.now()
 206                         batmsg.voltage = volt
 207                         batmsg.current = current
 208                         batmsg.charge = self.battery_capacity/3600.0
 209                         batmsg.capacity = float('nan')
 210                         batmsg.design_capacity = BATTERY_CAPACITY_FULL
 211                         batmsg.percentage = batmsg.charge/batmsg.design_capacity
 212                         batmsg.power_supply_status = BatteryState.POWER_SUPPLY_STATUS_DISCHARGING
 213                         batmsg.power_supply_health = BatteryState.POWER_SUPPLY_HEALTH_UNKNOWN
 214                         batmsg.power_supply_technology = BatteryState.POWER_SUPPLY_TECHNOLOGY_NIMH
 215                         batmsg.present = True
 216                         self.pub_battery.publish(batmsg)
 217
 218         def update_capacity(self, volt, current):
 219                 if self.bDocked:
 220                         self.battery_capacity = BATTERY_CAPACITY_FULL*3600
 221                 else:
 222                         self.battery_capacity -= current/UPDATE_RATE
 223
 224         def get_odom(self):
 225                 speed_trans, speed_rot, posx, posy, angle = struct.unpack(">fffff", i2c_read_reg(0x50, 0x38, 20))
 226                 current_time = rospy.Time.now()
 227
 228                 # since all odometry is 6DOF we'll need a quaternion created from yaw
 229                 odom_quat = tf.transformations.quaternion_from_euler(0, 0, angle)
 230
 231                 # first, we'll publish the transform over tf
 232                 if self.tf_broadcaster is not None:
 233                         self.tf_broadcaster.sendTransform((posx, posy, 0.0), odom_quat, current_time, "base_footprint", "odom")
 234
 235                 # next, we'll publish the odometry message over ROS
 236                 odom = Odometry()
 237                 odom.header.stamp = current_time
 238                 odom.header.frame_id = "odom"
 239
 240                 # set the position
 241                 odom.pose.pose.position.x = posx
 242                 odom.pose.pose.position.y = posy
 243                 odom.pose.pose.position.z = 0.0
 244                 odom.pose.pose.orientation.x = odom_quat[0]
 245                 odom.pose.pose.orientation.y = odom_quat[1]
 246                 odom.pose.pose.orientation.z = odom_quat[2]
 247                 odom.pose.pose.orientation.w = odom_quat[3]
 248                 odom.pose.covariance[0] = self.odom_covar_xy # x
 249                 odom.pose.covariance[7] = self.odom_covar_xy # y
 250                 odom.pose.covariance[14] = self.odom_covar_xy # z
 251                 odom.pose.covariance[21] = self.odom_covar_angle # rotation about X axis
 252                 odom.pose.covariance[28] = self.odom_covar_angle # rotation about Y axis
 253                 odom.pose.covariance[35] = self.odom_covar_angle # rotation about Z axis
 254
 255                 # set the velocity
 256                 odom.child_frame_id = "base_footprint"
 257                 odom.twist.twist.linear.x = speed_trans
 258                 odom.twist.twist.linear.y = 0.0
 259                 odom.twist.twist.linear.z = 0.0
 260                 odom.twist.twist.angular.z = speed_rot
 261                 odom.twist.covariance = odom.pose.covariance
 262
 263                 # publish the message
 264                 self.pub_odom.publish(odom)
 265
 266
 267         def set_speed(self, trans, rot):
 268                 i2c_write_reg(0x50, 0x50, struct.pack(">ff", trans, rot))
 269
 270         def cmdVelReceived(self, msg):
 271                 if not self.bMotorManual:
 272                         rospy.logdebug("Set new cmd_vel: %.2f %.2f", msg.linear.x, msg.angular.z)
 273                         self.cmd_vel = (msg.linear.x, msg.angular.z) # commit speed on next update cycle
 274                         rospy.logdebug("Set new cmd_vel done")
 275
 276         # http://rn-wissen.de/wiki/index.php/Sensorarten#Sharp_GP2D12
 277         def get_dist_ir(self, num):
 278                 dev = i2c(0x52)
 279                 s = struct.pack("B", num)
 280                 dev.write(s)
 281                 dev.close()
 282
 283                 sleep(2e-6)
 284
 285                 dev = i2c(0x52)
 286                 s = dev.read(2)
 287                 dev.close()
 288
 289                 val = struct.unpack(">H", s)[0]
 290                 return val
 291
 292         def start_dist_srf(self, num):
 293                 dev = i2c(0x52)
 294                 s = struct.pack("B", num)
 295                 dev.write(s)
 296                 dev.close()
 297
 298         def read_dist_srf(self, num):
 299                 return struct.unpack(">H", i2c_read_reg(0x52, num, 2))[0]/1000.0
 300
 301         def send_range(self, pub, frame_id, typ, dist, min_range, max_range, fov_deg):
 302                 if self.bClipRangeSensor and dist > max_range:
 303                         dist = max_range
 304                 msg = Range()
 305                 msg.header.stamp = rospy.Time.now()
 306                 msg.header.frame_id = frame_id
 307                 msg.radiation_type = typ
 308                 msg.field_of_view = fov_deg*pi/180
 309                 msg.min_range = min_range
 310                 msg.max_range = max_range
 311                 msg.range = dist
 312                 pub.publish(msg)
 313
 314         def get_dist_left(self):
 315                 if self.pub_range_left.get_num_connections() > 0:
 316                         dist = self.get_dist_ir(0x1)
 317                         if dist > -67:
 318                                 self.send_range(self.pub_range_left, "ir_left", Range.INFRARED, 30.553/(dist - -67.534), 0.04, 0.3, 1)
 319
 320         def get_dist_right(self):
 321                 if self.pub_range_right.get_num_connections() > 0:
 322                         dist = self.get_dist_ir(0x3)
 323                         if dist > 69:
 324                                 self.send_range(self.pub_range_right, "ir_right", Range.INFRARED, 17.4/(dist - 69), 0.04, 0.3, 1)
 325
 326         def get_dist_forward_left(self):
 327                 if self.pub_range_fwd_left.get_num_connections() > 0:
 328                         dist = self.read_dist_srf(0x15)
 329                         self.send_range(self.pub_range_fwd_left, "sonar_forward_left", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 330
 331         def update_dist_forward_left(self):
 332                 if self.pub_range_fwd_left.get_num_connections() > 0:
 333                         self.start_dist_srf(0x5)
 334
 335         def get_dist_backward(self):
 336                 if self.pub_range_bwd.get_num_connections() > 0:
 337                         dist = self.read_dist_srf(0x17)
 338                         self.send_range(self.pub_range_bwd, "sonar_backward", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 339
 340         def update_dist_backward(self):
 341                 if self.pub_range_bwd.get_num_connections() > 0:
 342                         self.start_dist_srf(0x7)
 343
 344         def get_dist_forward_right(self):
 345                 if self.pub_range_fwd_right.get_num_connections() > 0:
 346                         dist = self.read_dist_srf(0x19)
 347                         self.send_range(self.pub_range_fwd_right, "sonar_forward_right", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 348
 349         def update_dist_forward_right(self):
 350                 if self.pub_range_fwd_right.get_num_connections() > 0:
 351                         self.start_dist_srf(0xb)
 352
 353         def check_docked(self):
 354                 if self.bDocked and not self.bDocked_last:
 355                         rospy.loginfo("Docking event")
 356                 elif not self.bDocked and self.bDocked_last:
 357                         if not self.bStayDocked or self.cur_vel != (0, 0):
 358                                 rospy.loginfo("Undocking event")
 359                         else:
 360                                 rospy.loginfo("Undocking event..redocking")
 361                                 thread.start_new_thread(self.redock, ())
 362
 363                 self.bDocked_last = self.bDocked
 364
 365         def redock(self):
 366                 self.cmd_vel = (-0.1, 0)
 367                 for i in range(100):
 368                         if self.bDocked:
 369                                 break
 370                         sleep(0.01)
 371                 self.cmd_vel = (0, 0)
 372                 if self.bDocked:
 373                         rospy.loginfo("Redocking done")
 374                 else:
 375                         rospy.logerr("Redocking failed")
 376
 377
 378 if __name__ == "__main__":
 379         WTBase()