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.msg import LedStripe
  19 from wild_thumper.cfg import WildThumperConfig
  20
  21 WHEEL_DIST = 0.248
  22
  23 class LPD8806:
  24         def __init__(self, bus, device, num_leds):
  25                 self.spi = spidev.SpiDev()
  26                 self.spi.open(bus, device)
  27                 self.spi.mode=0b00
  28                 self.spi.max_speed_hz=int(2e6)
  29                 self.num_leds = num_leds
  30                 self.latch()
  31                 self.l = [(0, 0, 0)] * num_leds
  32                 self.update()
  33
  34         def set(self, i, red=0, green=0, blue=0):
  35                 if red > 127 or green > 127 or blue > 127 or red < 0 or green < 0 or blue < 0:
  36                         raise Exception("Bad RGB Value")
  37                 self.l[i] = (red, green, blue)
  38
  39         def latch(self):
  40                 self.spi.writebytes([0x0 for i in range((self.num_leds+31)/32)])
  41
  42         def update(self):
  43                 l = []
  44                 for i in range(self.num_leds):
  45                         red, green, blue = self.l[i]
  46                         l.append(0x80 | green)
  47                         l.append(0x80 | red)
  48                         l.append(0x80 | blue)
  49                 self.spi.writebytes(l)
  50                 self.latch()
  51
  52 class WTBase:
  53         def __init__(self):
  54                 rospy.init_node('wild_thumper')
  55                 prctl.set_name("wild_thumper")
  56                 enable_odom_tf = rospy.get_param("~enable_odom_tf", True)
  57                 if enable_odom_tf:
  58                         self.tf_broadcaster = tf.broadcaster.TransformBroadcaster()
  59                 else:
  60                         self.tf_broadcaster = None
  61                 self.dyn_conf = Server(WildThumperConfig, self.execute_dyn_reconf)
  62                 self.pub_odom = rospy.Publisher("odom", Odometry, queue_size=16)
  63                 self.pub_diag = rospy.Publisher("diagnostics", DiagnosticArray, queue_size=16)
  64                 self.pub_range_fwd_left = rospy.Publisher("range_forward_left", Range, queue_size=16)
  65                 self.pub_range_fwd_right = rospy.Publisher("range_forward_right", Range, queue_size=16)
  66                 self.pub_range_bwd = rospy.Publisher("range_backward", Range, queue_size=16)
  67                 self.pub_range_left = rospy.Publisher("range_left", Range, queue_size=16)
  68                 self.pub_range_right = rospy.Publisher("range_right", Range, queue_size=16)
  69                 self.pub_battery = rospy.Publisher("battery", BatteryState, queue_size=16)
  70                 self.cmd_vel = None
  71                 self.cur_vel = (0, 0)
  72                 self.bMotorManual = False
  73                 self.set_speed(0, 0)
  74                 self.volt_last_warn = rospy.Time.now()
  75                 rospy.loginfo("Init done")
  76                 i2c_write_reg(0x50, 0x90, struct.pack("BB", 1, 1)) # switch direction
  77                 self.pStripe = LPD8806(1, 0, 12)
  78                 rospy.Subscriber("cmd_vel_out", Twist, self.cmdVelReceived)
  79                 rospy.Subscriber("led_stripe", LedStripe, self.led_stripe_received)
  80                 rospy.Subscriber("imu", Imu, self.imuReceived)
  81                 self.bDocked = False
  82                 self.bDocked_last = False
  83                 self.run()
  84
  85         def run(self):
  86                 rate = rospy.Rate(20.0)
  87                 sleep(3) # wait 3s for ros to register and establish all subscriber connections before sending reset diag
  88                 reset_val = self.get_reset()
  89                 rospy.loginfo("Reset Status: 0x%x" % reset_val)
  90                 ir_count = 0
  91                 sonar_count = 0
  92                 while not rospy.is_shutdown():
  93                         rospy.logdebug("Loop alive")
  94                         #print struct.unpack(">B", i2c_read_reg(0x50, 0xA2, 1))[0] # count test
  95                         self.get_motor_err()
  96                         self.get_odom()
  97                         self.get_voltage()
  98
  99                         if ir_count == 0:
 100                                 self.get_dist_left()
 101                                 ir_count+=1
 102                         else:
 103                                 self.get_dist_right()
 104                                 ir_count=0
 105
 106                         if sonar_count == 0:
 107                                 self.get_dist_forward_left()
 108                                 self.update_dist_backward()
 109                                 sonar_count+=1
 110                         elif sonar_count == 1:
 111                                 self.get_dist_backward()
 112                                 self.update_dist_forward_right()
 113                                 sonar_count+=1
 114                         elif sonar_count == 2:
 115                                 self.get_dist_forward_right()
 116                                 self.update_dist_forward_left()
 117                                 sonar_count=0
 118
 119                         if self.cmd_vel != None:
 120                                 self.set_speed(self.cmd_vel[0], self.cmd_vel[1])
 121                                 self.cur_vel = self.cmd_vel
 122                                 self.cmd_vel = None
 123
 124                         self.check_docked()
 125                         rate.sleep()
 126
 127         def execute_dyn_reconf(self, config, level):
 128                 self.bClipRangeSensor = config["range_sensor_clip"]
 129                 self.range_sensor_max = config["range_sensor_max"]
 130                 self.range_sensor_fov = config["range_sensor_fov"]
 131                 self.odom_covar_xy = config["odom_covar_xy"]
 132                 self.odom_covar_angle = config["odom_covar_angle"]
 133                 self.rollover_protect = config["rollover_protect"]
 134                 self.rollover_protect_limit = config["rollover_protect_limit"]
 135                 self.rollover_protect_pwm = config["rollover_protect_pwm"]
 136                 self.bStayDocked = config["stay_docked"]
 137
 138                 return config
 139
 140         def imuReceived(self, msg):
 141                 if self.rollover_protect and any(self.cur_vel):
 142                         (roll, pitch, yaw) = tf.transformations.euler_from_quaternion(msg.orientation.__getstate__())
 143                         if pitch > self.rollover_protect_limit*pi/180:
 144                                 self.bMotorManual = True
 145                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", 0, self.rollover_protect_pwm, 0, self.rollover_protect_pwm))
 146                                 rospy.logwarn("Running forward rollver protection")
 147                         elif pitch < -self.rollover_protect_limit*pi/180:
 148                                 self.bMotorManual = True
 149                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", -self.rollover_protect_pwm, 0, -self.rollover_protect_pwm, 0))
 150                                 rospy.logwarn("Running backward rollver protection")
 151                         elif self.bMotorManual:
 152                                 i2c_write_reg(0x50, 0x1, struct.pack(">hhhh", 0, 0, 0, 0))
 153                                 self.bMotorManual = False
 154                                 self.cmd_vel = (0, 0)
 155                                 rospy.logwarn("Rollver protection done")
 156
 157         def get_reset(self):
 158                 reset = struct.unpack(">B", i2c_read_reg(0x50, 0xA0, 1))[0]
 159
 160                 msg = DiagnosticArray()
 161                 msg.header.stamp = rospy.Time.now()
 162                 stat = DiagnosticStatus()
 163                 stat.name = "Reset reason"
 164                 stat.level = DiagnosticStatus.ERROR if reset & 0x0c else DiagnosticStatus.OK
 165                 stat.message = "0x%02x" % reset
 166
 167                 wdrf = bool(reset & (1 << 3))
 168                 if wdrf: rospy.loginfo("Watchdog Reset")
 169                 borf = bool(reset & (1 << 2))
 170                 if borf: rospy.loginfo("Brown-out Reset Flag")
 171                 extrf = bool(reset & (1 << 1))
 172                 if extrf: rospy.loginfo("External Reset Flag")
 173                 porf = bool(reset & (1 << 0))
 174                 if porf: rospy.loginfo("Power-on Reset Flag")
 175                 stat.values.append(KeyValue("Watchdog Reset Flag", str(wdrf)))
 176                 stat.values.append(KeyValue("Brown-out Reset Flag", str(borf)))
 177                 stat.values.append(KeyValue("External Reset Flag", str(extrf)))
 178                 stat.values.append(KeyValue("Power-on Reset Flag", str(porf)))
 179
 180                 msg.status.append(stat)
 181                 self.pub_diag.publish(msg)
 182                 return reset
 183
 184
 185         def get_motor_err(self):
 186                 err = struct.unpack(">B", i2c_read_reg(0x50, 0xA1, 1))[0]
 187
 188                 msg = DiagnosticArray()
 189                 msg.header.stamp = rospy.Time.now()
 190                 stat = DiagnosticStatus()
 191                 stat.name = "Motor: Error Status"
 192                 stat.level = DiagnosticStatus.ERROR if err else DiagnosticStatus.OK
 193                 stat.message = "0x%02x" % err
 194
 195                 # Diag
 196                 stat.values.append(KeyValue("aft left diag", str(bool(err & (1 << 0)))))
 197                 stat.values.append(KeyValue("front left diag", str(bool(err & (1 << 1)))))
 198                 stat.values.append(KeyValue("aft right diag", str(bool(err & (1 << 2)))))
 199                 stat.values.append(KeyValue("front right diag", str(bool(err & (1 << 3)))))
 200                 # Stall
 201                 stat.values.append(KeyValue("aft left stall", str(bool(err & (1 << 4)))))
 202                 stat.values.append(KeyValue("front left stall", str(bool(err & (1 << 5)))))
 203                 stat.values.append(KeyValue("aft right stall", str(bool(err & (1 << 6)))))
 204                 stat.values.append(KeyValue("front right stall", str(bool(err & (1 << 7)))))
 205
 206                 msg.status.append(stat)
 207                 self.pub_diag.publish(msg)
 208
 209         def get_voltage(self):
 210                 volt = struct.unpack(">h", i2c_read_reg(0x52, 0x09, 2))[0]/100.0
 211
 212                 msg = DiagnosticArray()
 213                 msg.header.stamp = rospy.Time.now()
 214                 stat = DiagnosticStatus()
 215                 stat.name = "Voltage"
 216                 stat.level = DiagnosticStatus.ERROR if volt < 7 else DiagnosticStatus.OK
 217                 stat.message = "%.2fV" % volt
 218
 219                 msg.status.append(stat)
 220                 self.pub_diag.publish(msg)
 221
 222                 if self.pub_battery.get_num_connections() > 0:
 223                         batmsg = BatteryState()
 224                         batmsg.header.stamp = rospy.Time.now()
 225                         batmsg.voltage = volt
 226                         batmsg.current = float('nan')
 227                         batmsg.charge = float('nan')
 228                         batmsg.capacity = float('nan')
 229                         batmsg.design_capacity = 5.0
 230                         batmsg.percentage = float('nan')
 231                         batmsg.power_supply_status = BatteryState.POWER_SUPPLY_STATUS_DISCHARGING
 232                         batmsg.power_supply_health = BatteryState.POWER_SUPPLY_HEALTH_UNKNOWN
 233                         batmsg.power_supply_technology = BatteryState.POWER_SUPPLY_TECHNOLOGY_NIMH
 234                         self.pub_battery.publish(batmsg)
 235
 236                 if volt < 7 and (rospy.Time.now() - self.volt_last_warn).to_sec() > 10:
 237                         rospy.logerr("Voltage critical: %.2fV" % (volt))
 238                         self.volt_last_warn = rospy.Time.now()
 239
 240                 self.bDocked = volt > 10
 241
 242
 243         def get_odom(self):
 244                 speed_trans, speed_rot, posx, posy, angle = struct.unpack(">fffff", i2c_read_reg(0x50, 0x38, 20))
 245                 current_time = rospy.Time.now()
 246
 247                 # since all odometry is 6DOF we'll need a quaternion created from yaw
 248                 odom_quat = tf.transformations.quaternion_from_euler(0, 0, angle)
 249
 250                 # first, we'll publish the transform over tf
 251                 if self.tf_broadcaster is not None:
 252                         self.tf_broadcaster.sendTransform((posx, posy, 0.0), odom_quat, current_time, "base_footprint", "odom")
 253
 254                 # next, we'll publish the odometry message over ROS
 255                 odom = Odometry()
 256                 odom.header.stamp = current_time
 257                 odom.header.frame_id = "odom"
 258
 259                 # set the position
 260                 odom.pose.pose.position.x = posx
 261                 odom.pose.pose.position.y = posy
 262                 odom.pose.pose.position.z = 0.0
 263                 odom.pose.pose.orientation.x = odom_quat[0]
 264                 odom.pose.pose.orientation.y = odom_quat[1]
 265                 odom.pose.pose.orientation.z = odom_quat[2]
 266                 odom.pose.pose.orientation.w = odom_quat[3]
 267                 odom.pose.covariance[0] = self.odom_covar_xy # x
 268                 odom.pose.covariance[7] = self.odom_covar_xy # y
 269                 odom.pose.covariance[14] = self.odom_covar_xy # z
 270                 odom.pose.covariance[21] = self.odom_covar_angle # rotation about X axis
 271                 odom.pose.covariance[28] = self.odom_covar_angle # rotation about Y axis
 272                 odom.pose.covariance[35] = self.odom_covar_angle # rotation about Z axis
 273
 274                 # set the velocity
 275                 odom.child_frame_id = "base_footprint"
 276                 odom.twist.twist.linear.x = speed_trans
 277                 odom.twist.twist.linear.y = 0.0
 278                 odom.twist.twist.linear.z = 0.0
 279                 odom.twist.twist.angular.z = speed_rot
 280                 odom.twist.covariance = odom.pose.covariance
 281
 282                 # publish the message
 283                 self.pub_odom.publish(odom)
 284
 285
 286         def set_speed(self, trans, rot):
 287                 i2c_write_reg(0x50, 0x50, struct.pack(">ff", trans, rot))
 288
 289         def cmdVelReceived(self, msg):
 290                 if not self.bMotorManual:
 291                         rospy.logdebug("Set new cmd_vel: %.2f %.2f", msg.linear.x, msg.angular.z)
 292                         self.cmd_vel = (msg.linear.x, msg.angular.z) # commit speed on next update cycle
 293                         rospy.logdebug("Set new cmd_vel done")
 294
 295         # http://rn-wissen.de/wiki/index.php/Sensorarten#Sharp_GP2D12
 296         def get_dist_ir(self, num):
 297                 dev = i2c(0x52)
 298                 s = struct.pack("B", num)
 299                 dev.write(s)
 300                 dev.close()
 301
 302                 sleep(2e-6)
 303
 304                 dev = i2c(0x52)
 305                 s = dev.read(2)
 306                 dev.close()
 307
 308                 val = struct.unpack(">H", s)[0]
 309                 return val
 310
 311         def start_dist_srf(self, num):
 312                 dev = i2c(0x52)
 313                 s = struct.pack("B", num)
 314                 dev.write(s)
 315                 dev.close()
 316
 317         def read_dist_srf(self, num):
 318                 return struct.unpack(">H", i2c_read_reg(0x52, num, 2))[0]/1000.0
 319
 320         def send_range(self, pub, frame_id, typ, dist, min_range, max_range, fov_deg):
 321                 if self.bClipRangeSensor and dist > max_range:
 322                         dist = max_range
 323                 msg = Range()
 324                 msg.header.stamp = rospy.Time.now()
 325                 msg.header.frame_id = frame_id
 326                 msg.radiation_type = typ
 327                 msg.field_of_view = fov_deg*pi/180
 328                 msg.min_range = min_range
 329                 msg.max_range = max_range
 330                 msg.range = dist
 331                 pub.publish(msg)
 332
 333         def get_dist_left(self):
 334                 if self.pub_range_left.get_num_connections() > 0:
 335                         dist = self.get_dist_ir(0x1)
 336                         if dist > -67:
 337                                 self.send_range(self.pub_range_left, "ir_left", Range.INFRARED, 30.553/(dist - -67.534), 0.04, 0.3, 1)
 338
 339         def get_dist_right(self):
 340                 if self.pub_range_right.get_num_connections() > 0:
 341                         dist = self.get_dist_ir(0x3)
 342                         if dist > 69:
 343                                 self.send_range(self.pub_range_right, "ir_right", Range.INFRARED, 17.4/(dist - 69), 0.04, 0.3, 1)
 344
 345         def get_dist_forward_left(self):
 346                 if self.pub_range_fwd_left.get_num_connections() > 0:
 347                         dist = self.read_dist_srf(0x15)
 348                         self.send_range(self.pub_range_fwd_left, "sonar_forward_left", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 349
 350         def update_dist_forward_left(self):
 351                 if self.pub_range_fwd_left.get_num_connections() > 0:
 352                         self.start_dist_srf(0x5)
 353
 354         def get_dist_backward(self):
 355                 if self.pub_range_bwd.get_num_connections() > 0:
 356                         dist = self.read_dist_srf(0x17)
 357                         self.send_range(self.pub_range_bwd, "sonar_backward", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 358
 359         def update_dist_backward(self):
 360                 if self.pub_range_bwd.get_num_connections() > 0:
 361                         self.start_dist_srf(0x7)
 362
 363         def get_dist_forward_right(self):
 364                 if self.pub_range_fwd_right.get_num_connections() > 0:
 365                         dist = self.read_dist_srf(0x19)
 366                         self.send_range(self.pub_range_fwd_right, "sonar_forward_right", Range.ULTRASOUND, dist, 0.04, self.range_sensor_max, self.range_sensor_fov)
 367
 368         def update_dist_forward_right(self):
 369                 if self.pub_range_fwd_right.get_num_connections() > 0:
 370                         self.start_dist_srf(0xb)
 371
 372         def led_stripe_received(self, msg):
 373                 for led in msg.leds:
 374                         self.pStripe.set(led.num, red=led.red, green=led.green, blue=led.blue)
 375                         self.pStripe.update()
 376
 377         def check_docked(self):
 378                 if self.bDocked and not self.bDocked_last:
 379                         rospy.loginfo("Docking event")
 380                 elif not self.bDocked and self.bDocked_last:
 381                         if not self.bStayDocked or self.cur_vel != (0, 0):
 382                                 rospy.loginfo("Undocking event")
 383                         else:
 384                                 rospy.loginfo("Undocking event..redocking")
 385                                 thread.start_new_thread(self.redock, ())
 386
 387                 self.bDocked_last = self.bDocked
 388
 389         def redock(self):
 390                 self.cmd_vel = (-0.1, 0)
 391                 for i in range(100):
 392                         if self.bDocked:
 393                                 break
 394                         sleep(0.01)
 395                 self.cmd_vel = (0, 0)
 396                 if self.bDocked:
 397                         rospy.loginfo("Redocking done")
 398                 else:
 399                         rospy.logerr("Redocking failed")
 400
 401
 402 if __name__ == "__main__":
 403         WTBase()