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
  22 class WTBase:
  23         def __init__(self):
  24                 rospy.init_node('wild_thumper')
  25                 prctl.set_name("wild_thumper")
  26                 enable_odom_tf = rospy.get_param("~enable_odom_tf", True)
  27                 if enable_odom_tf:
  28                         self.tf_broadcaster = tf.broadcaster.TransformBroadcaster()
  29                 else:
  30                         self.tf_broadcaster = None
  31                 self.dyn_conf = Server(WildThumperConfig, self.execute_dyn_reconf)
  32                 self.pub_odom = rospy.Publisher("odom", Odometry, queue_size=16)
  33                 self.pub_diag = rospy.Publisher("diagnostics", DiagnosticArray, queue_size=16)
  34                 self.pub_range_fwd_left = rospy.Publisher("range_forward_left", Range, queue_size=16)
  35                 self.pub_range_fwd_right = rospy.Publisher("range_forward_right", Range, queue_size=16)
  36                 self.pub_range_bwd = rospy.Publisher("range_backward", Range, queue_size=16)
  37                 self.pub_range_left = rospy.Publisher("range_left", Range, queue_size=16)
  38                 self.pub_range_right = rospy.Publisher("range_right", Range, queue_size=16)
  39                 self.pub_battery = rospy.Publisher("battery", BatteryState, queue_size=16)
  40                 self.cmd_vel = None
  41                 self.cur_vel = (0, 0)
  42                 self.bMotorManual = False
  43                 self.set_speed(0, 0)
  44                 self.volt_last_warn = rospy.Time.now()
  45                 rospy.loginfo("Init done")
  46                 i2c_write_reg(0x50, 0x90, struct.pack("BB", 1, 1)) # switch direction
  47                 rospy.Subscriber("cmd_vel_out", Twist, self.cmdVelReceived)
  48                 rospy.Subscriber("imu", Imu, self.imuReceived)
  49                 self.bDocked = False
  50                 self.bDocked_last = False
  51                 self.run()
  52
  53         def run(self):
  54                 rate = rospy.Rate(20.0)
  55                 sleep(3) # wait 3s for ros to register and establish all subscriber connections before sending reset diag
  56                 reset_val = self.get_reset()
  57                 rospy.loginfo("Reset Status: 0x%x" % reset_val)
  58                 ir_count = 0
  59                 sonar_count = 0
  60                 while not rospy.is_shutdown():
  61                         rospy.logdebug("Loop alive")
  62                         #print struct.unpack(">B", i2c_read_reg(0x50, 0xA2, 1))[0] # count test
  63                         self.get_motor_err()
  64                         self.get_odom()
  65                         self.get_power()
  66
  67                         if ir_count == 0:
  68                                 self.get_dist_left()
  69                                 ir_count+=1
  70                         else:
  71                                 self.get_dist_right()
  72                                 ir_count=0
  73
  74                         if sonar_count == 0:
  75                                 self.get_dist_forward_left()
  76                                 self.update_dist_backward()
  77                                 sonar_count+=1
  78                         elif sonar_count == 1:
  79                                 self.get_dist_backward()
  80                                 self.update_dist_forward_right()
  81                                 sonar_count+=1
  82                         elif sonar_count == 2:
  83                                 self.get_dist_forward_right()
  84                                 self.update_dist_forward_left()
  85                                 sonar_count=0
  86
  87                         if self.cmd_vel != None:
  88                                 self.set_speed(self.cmd_vel[0], self.cmd_vel[1])
  89                                 self.cur_vel = self.cmd_vel
  90                                 self.cmd_vel = None
  91
  92                         self.check_docked()
  93                         rate.sleep()
  94
  95         def execute_dyn_reconf(self, config, level):
  96                 self.bClipRangeSensor = config["range_sensor_clip"]
  97                 self.range_sensor_max = config["range_sensor_max"]
  98                 self.range_sensor_fov = config["range_sensor_fov"]
  99                 self.odom_covar_xy = config["odom_covar_xy"]
 100                 self.odom_covar_angle = config["odom_covar_angle"]
 101                 self.rollover_protect = config["rollover_protect"]
 102                 self.rollover_protect_limit = config["rollover_protect_limit"]
 103                 self.rollover_protect_pwm = config["rollover_protect_pwm"]
 104                 self.bStayDocked = config["stay_docked"]
 105
 106                 return config
 107
 108         def imuReceived(self, msg):
 109                 if self.rollover_protect and (any(self.cur_vel) or self.bMotorManual):
 110                         (roll, pitch, yaw) = tf.transformations.euler_from_quaternion(msg.orientation.__getstate__())
 111                         if pitch > self.rollover_protect_limit*pi/180:
 112                                 self.bMotorManual = True
 113                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", 0, self.rollover_protect_pwm, 0, self.rollover_protect_pwm))
 114                                 rospy.logwarn("Running forward rollver protection")
 115                         elif pitch < -self.rollover_protect_limit*pi/180:
 116                                 self.bMotorManual = True
 117                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", -self.rollover_protect_pwm, 0, -self.rollover_protect_pwm, 0))
 118                                 rospy.logwarn("Running backward rollver protection")
 119                         elif self.bMotorManual:
 120                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", 0, 0, 0, 0))
 121                                 self.bMotorManual = False
 122                                 self.cmd_vel = (0, 0)
 123                                 rospy.logwarn("Rollver protection done")
 124
 125         def get_reset(self):
 126                 reset = struct.unpack(">B", i2c_read_reg(0x50, 0xA0, 1))[0]
 127
 128                 msg = DiagnosticArray()
 129                 msg.header.stamp = rospy.Time.now()
 130                 stat = DiagnosticStatus()
 131                 stat.name = "Reset reason"
 132                 stat.level = DiagnosticStatus.ERROR if reset & 0x0c else DiagnosticStatus.OK
 133                 stat.message = "0x%02x" % reset
 134
 135                 wdrf = bool(reset & (1 << 3))
 136                 if wdrf: rospy.loginfo("Watchdog Reset")
 137                 borf = bool(reset & (1 << 2))
 138                 if borf: rospy.loginfo("Brown-out Reset Flag")
 139                 extrf = bool(reset & (1 << 1))
 140                 if extrf: rospy.loginfo("External Reset Flag")
 141                 porf = bool(reset & (1 << 0))
 142                 if porf: rospy.loginfo("Power-on Reset Flag")
 143                 stat.values.append(KeyValue("Watchdog Reset Flag", str(wdrf)))
 144                 stat.values.append(KeyValue("Brown-out Reset Flag", str(borf)))
 145                 stat.values.append(KeyValue("External Reset Flag", str(extrf)))
 146                 stat.values.append(KeyValue("Power-on Reset Flag", str(porf)))
 147
 148                 msg.status.append(stat)
 149                 self.pub_diag.publish(msg)
 150                 return reset
 151
 152
 153         def get_motor_err(self):
 154                 err = struct.unpack(">B", i2c_read_reg(0x50, 0xA1, 1))[0]
 155
 156                 msg = DiagnosticArray()
 157                 msg.header.stamp = rospy.Time.now()
 158                 stat = DiagnosticStatus()
 159                 stat.name = "Motor: Error Status"
 160                 stat.level = DiagnosticStatus.ERROR if err else DiagnosticStatus.OK
 161                 stat.message = "0x%02x" % err
 162
 163                 # Diag
 164                 stat.values.append(KeyValue("aft left diag", str(bool(err & (1 << 0)))))
 165                 stat.values.append(KeyValue("front left diag", str(bool(err & (1 << 1)))))
 166                 stat.values.append(KeyValue("aft right diag", str(bool(err & (1 << 2)))))
 167                 stat.values.append(KeyValue("front right diag", str(bool(err & (1 << 3)))))
 168                 # Stall
 169                 stat.values.append(KeyValue("aft left stall", str(bool(err & (1 << 4)))))
 170                 stat.values.append(KeyValue("front left stall", str(bool(err & (1 << 5)))))
 171                 stat.values.append(KeyValue("aft right stall", str(bool(err & (1 << 6)))))
 172                 stat.values.append(KeyValue("front right stall", str(bool(err & (1 << 7)))))
 173
 174                 msg.status.append(stat)
 175                 self.pub_diag.publish(msg)
 176
 177         def get_power(self):
 178                 volt = struct.unpack(">h", i2c_read_reg(0x52, 0x09, 2))[0]/100.0
 179                 current = struct.unpack(">h", i2c_read_reg(0x52, 0x0D, 2))[0]/1000.0
 180
 181                 msg = DiagnosticArray()
 182                 msg.header.stamp = rospy.Time.now()
 183                 stat = DiagnosticStatus()
 184                 stat.name = "Power"
 185                 stat.level = DiagnosticStatus.ERROR if volt < 7 or current > 5 else DiagnosticStatus.OK
 186                 stat.message = "%.2fV, %.2fA" % (volt, current)
 187
 188                 msg.status.append(stat)
 189                 self.pub_diag.publish(msg)
 190
 191                 if self.pub_battery.get_num_connections() > 0:
 192                         batmsg = BatteryState()
 193                         batmsg.header.stamp = rospy.Time.now()
 194                         batmsg.voltage = volt
 195                         batmsg.current = current
 196                         batmsg.charge = float('nan')
 197                         batmsg.capacity = float('nan')
 198                         batmsg.design_capacity = 5.0
 199                         batmsg.percentage = float('nan')
 200                         batmsg.power_supply_status = BatteryState.POWER_SUPPLY_STATUS_DISCHARGING
 201                         batmsg.power_supply_health = BatteryState.POWER_SUPPLY_HEALTH_UNKNOWN
 202                         batmsg.power_supply_technology = BatteryState.POWER_SUPPLY_TECHNOLOGY_NIMH
 203                         self.pub_battery.publish(batmsg)
 204
 205                 if volt < 7 and (rospy.Time.now() - self.volt_last_warn).to_sec() > 10:
 206                         rospy.logerr("Voltage critical: %.2fV" % (volt))
 207                         self.volt_last_warn = rospy.Time.now()
 208
 209                 self.bDocked = volt > 10.1
 210
 211
 212         def get_odom(self):
 213                 speed_trans, speed_rot, posx, posy, angle = struct.unpack(">fffff", i2c_read_reg(0x50, 0x38, 20))
 214                 current_time = rospy.Time.now()
 215
 216                 # since all odometry is 6DOF we'll need a quaternion created from yaw
 217                 odom_quat = tf.transformations.quaternion_from_euler(0, 0, angle)
 218
 219                 # first, we'll publish the transform over tf
 220                 if self.tf_broadcaster is not None:
 221                         self.tf_broadcaster.sendTransform((posx, posy, 0.0), odom_quat, current_time, "base_footprint", "odom")
 222
 223                 # next, we'll publish the odometry message over ROS
 224                 odom = Odometry()
 225                 odom.header.stamp = current_time
 226                 odom.header.frame_id = "odom"
 227
 228                 # set the position
 229                 odom.pose.pose.position.x = posx
 230                 odom.pose.pose.position.y = posy
 231                 odom.pose.pose.position.z = 0.0
 232                 odom.pose.pose.orientation.x = odom_quat[0]
 233                 odom.pose.pose.orientation.y = odom_quat[1]
 234                 odom.pose.pose.orientation.z = odom_quat[2]
 235                 odom.pose.pose.orientation.w = odom_quat[3]
 236                 odom.pose.covariance[0] = self.odom_covar_xy # x
 237                 odom.pose.covariance[7] = self.odom_covar_xy # y
 238                 odom.pose.covariance[14] = self.odom_covar_xy # z
 239                 odom.pose.covariance[21] = self.odom_covar_angle # rotation about X axis
 240                 odom.pose.covariance[28] = self.odom_covar_angle # rotation about Y axis
 241                 odom.pose.covariance[35] = self.odom_covar_angle # rotation about Z axis
 242
 243                 # set the velocity
 244                 odom.child_frame_id = "base_footprint"
 245                 odom.twist.twist.linear.x = speed_trans
 246                 odom.twist.twist.linear.y = 0.0
 247                 odom.twist.twist.linear.z = 0.0
 248                 odom.twist.twist.angular.z = speed_rot
 249                 odom.twist.covariance = odom.pose.covariance
 250
 251                 # publish the message
 252                 self.pub_odom.publish(odom)
 253
 254
 255         def set_speed(self, trans, rot):
 256                 i2c_write_reg(0x50, 0x50, struct.pack(">ff", trans, rot))
 257
 258         def cmdVelReceived(self, msg):
 259                 if not self.bMotorManual:
 260                         rospy.logdebug("Set new cmd_vel: %.2f %.2f", msg.linear.x, msg.angular.z)
 261                         self.cmd_vel = (msg.linear.x, msg.angular.z) # commit speed on next update cycle
 262                         rospy.logdebug("Set new cmd_vel done")
 263
 264         # http://rn-wissen.de/wiki/index.php/Sensorarten#Sharp_GP2D12
 265         def get_dist_ir(self, num):
 266                 dev = i2c(0x52)
 267                 s = struct.pack("B", num)
 268                 dev.write(s)
 269                 dev.close()
 270
 271                 sleep(2e-6)
 272
 273                 dev = i2c(0x52)
 274                 s = dev.read(2)
 275                 dev.close()
 276
 277                 val = struct.unpack(">H", s)[0]
 278                 return val
 279
 280         def start_dist_srf(self, num):
 281                 dev = i2c(0x52)
 282                 s = struct.pack("B", num)
 283                 dev.write(s)
 284                 dev.close()
 285
 286         def read_dist_srf(self, num):
 287                 return struct.unpack(">H", i2c_read_reg(0x52, num, 2))[0]/1000.0
 288
 289         def send_range(self, pub, frame_id, typ, dist, min_range, max_range, fov_deg):
 290                 if self.bClipRangeSensor and dist > max_range:
 291                         dist = max_range
 292                 msg = Range()
 293                 msg.header.stamp = rospy.Time.now()
 294                 msg.header.frame_id = frame_id
 295                 msg.radiation_type = typ
 296                 msg.field_of_view = fov_deg*pi/180
 297                 msg.min_range = min_range
 298                 msg.max_range = max_range
 299                 msg.range = dist
 300                 pub.publish(msg)
 301
 302         def get_dist_left(self):
 303                 if self.pub_range_left.get_num_connections() > 0:
 304                         dist = self.get_dist_ir(0x1)
 305                         if dist > -67:
 306                                 self.send_range(self.pub_range_left, "ir_left", Range.INFRARED, 30.553/(dist - -67.534), 0.04, 0.3, 1)
 307
 308         def get_dist_right(self):
 309                 if self.pub_range_right.get_num_connections() > 0:
 310                         dist = self.get_dist_ir(0x3)
 311                         if dist > 69:
 312                                 self.send_range(self.pub_range_right, "ir_right", Range.INFRARED, 17.4/(dist - 69), 0.04, 0.3, 1)
 313
 314         def get_dist_forward_left(self):
 315                 if self.pub_range_fwd_left.get_num_connections() > 0:
 316                         dist = self.read_dist_srf(0x15)
 317                         self.send_range(self.pub_range_fwd_left, "sonar_forward_left", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 318
 319         def update_dist_forward_left(self):
 320                 if self.pub_range_fwd_left.get_num_connections() > 0:
 321                         self.start_dist_srf(0x5)
 322
 323         def get_dist_backward(self):
 324                 if self.pub_range_bwd.get_num_connections() > 0:
 325                         dist = self.read_dist_srf(0x17)
 326                         self.send_range(self.pub_range_bwd, "sonar_backward", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 327
 328         def update_dist_backward(self):
 329                 if self.pub_range_bwd.get_num_connections() > 0:
 330                         self.start_dist_srf(0x7)
 331
 332         def get_dist_forward_right(self):
 333                 if self.pub_range_fwd_right.get_num_connections() > 0:
 334                         dist = self.read_dist_srf(0x19)
 335                         self.send_range(self.pub_range_fwd_right, "sonar_forward_right", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 336
 337         def update_dist_forward_right(self):
 338                 if self.pub_range_fwd_right.get_num_connections() > 0:
 339                         self.start_dist_srf(0xb)
 340
 341         def check_docked(self):
 342                 if self.bDocked and not self.bDocked_last:
 343                         rospy.loginfo("Docking event")
 344                 elif not self.bDocked and self.bDocked_last:
 345                         if not self.bStayDocked or self.cur_vel != (0, 0):
 346                                 rospy.loginfo("Undocking event")
 347                         else:
 348                                 rospy.loginfo("Undocking event..redocking")
 349                                 thread.start_new_thread(self.redock, ())
 350
 351                 self.bDocked_last = self.bDocked
 352
 353         def redock(self):
 354                 self.cmd_vel = (-0.1, 0)
 355                 for i in range(100):
 356                         if self.bDocked:
 357                                 break
 358                         sleep(0.01)
 359                 self.cmd_vel = (0, 0)
 360                 if self.bDocked:
 361                         rospy.loginfo("Redocking done")
 362                 else:
 363                         rospy.logerr("Redocking failed")
 364
 365
 366 if __name__ == "__main__":
 367         WTBase()