Gazebo-2 process has died

here is the terminal information:

NODES
/uav1/
iris_1_spawn (gazebo_ros/spawn_model)
mavros (mavros/mavros_node)
sitl_1 (px4/px4)
/uav0/
iris_0_spawn (gazebo_ros/spawn_model)
mavros (mavros/mavros_node)
sitl_0 (px4/px4)
/uav2/
iris_2_spawn (gazebo_ros/spawn_model)
mavros (mavros/mavros_node)
sitl_2 (px4/px4)
/
gazebo (gazebo_ros/gzserver)
gazebo_gui (gazebo_ros/gzclient)

auto-starting new master
process[master]: started with pid [4209]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to 12be4c92-20d5-11ea-b080-e4029be100e1
process[rosout-1]: started with pid [4222]
started core service [/rosout]
process[gazebo-2]: started with pid [4228]
process[gazebo_gui-3]: started with pid [4231]
process[uav0/sitl_0-4]: started with pid [4263]
process[uav0/iris_0_spawn-5]: started with pid [4266]
INFO [px4] Creating symlink /home/cactus/Firmware/ROMFS/px4fmu_common -> /home/cactus/.ros/sitl_iris_0/etc
0 WARNING: setRealtimeSched failed (not run as root?)


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px4 starting.

INFO [px4] Calling startup script: /bin/sh etc/init.d-posix/rcS 0
SYS_AUTOSTART: curr: 0 -> new: 10016
BAT_N_CELLS: curr: 0 -> new: 3
CAL_ACC0_ID: curr: 0 -> new: 1311244
CAL_ACC_PRIME: curr: 0 -> new: 1311244
CAL_GYRO0_ID: curr: 0 -> new: 2294028
CAL_GYRO_PRIME: curr: 0 -> new: 2294028
CAL_MAG0_ID: curr: 0 -> new: 197388
CAL_MAG_PRIME: curr: 0 -> new: 197388
CAL_BARO_PRIME: curr: 0 -> new: 6620172
COM_DISARM_LAND: curr: 2.0000 -> new: 0.1000
COM_OBL_ACT: curr: 0 -> new: 2
COM_OF_LOSS_T: curr: 0.0000 -> new: 5.0000
COM_RC_IN_MODE: curr: 0 -> new: 1
EKF2_ANGERR_INIT: curr: 0.1000 -> new: 0.0100
EKF2_GBIAS_INIT: curr: 0.1000 -> new: 0.0100
EKF2_REQ_GPS_H: curr: 10.0000 -> new: 0.5000
MC_PITCH_P: curr: 6.5000 -> new: 6.0000
MC_PITCHRATE_P: curr: 0.1500 -> new: 0.2000
MC_ROLL_P: curr: 6.5000 -> new: 6.0000
MC_ROLLRATE_P: curr: 0.1500 -> new: 0.2000
MPC_HOLD_MAX_Z: curr: 0.6000 -> new: 2.0000
MPC_Z_VEL_I: curr: 0.1000 -> new: 0.1500
MPC_Z_VEL_P: curr: 0.2000 -> new: 0.6000
MPC_XY_P: curr: 0.9500 -> new: 0.8000
MPC_XY_VEL_P: curr: 0.0900 -> new: 0.2000
MPC_XY_VEL_D: curr: 0.0100 -> new: 0.0160
MPC_JERK_MIN: curr: 8.0000 -> new: 10.0000
MPC_ACC_HOR_MAX: curr: 5.0000 -> new: 3.0000
NAV_ACC_RAD: curr: 10.0000 -> new: 2.0000
NAV_DLL_ACT: curr: 0 -> new: 2
RTL_DESCEND_ALT: curr: 30.0000 -> new: 5.0000
RTL_LAND_DELAY: curr: -1.0000 -> new: 5.0000
RTL_RETURN_ALT: curr: 60.0000 -> new: 30.0000
SDLOG_MODE: curr: 0 -> new: 1
SDLOG_PROFILE: curr: 3 -> new: 131
SDLOG_DIRS_MAX: curr: 0 -> new: 7
SENS_BOARD_X_OFF: curr: 0.0000 -> new: 0.0000
SENS_DPRES_OFF: curr: 0.0000 -> new: 0.0010
TRIG_INTERFACE: curr: 4 -> new: 3

  • RTL_DESCEND_ALT: curr: 5.0000 -> new: 10.0000
  • RTL_LAND_DELAY: curr: 5.0000 -> new: 0.0000
    PWM_MAX: curr: 2000 -> new: 1950
    PWM_MIN: curr: 1000 -> new: 1075
    process[uav0/mavros-6]: started with pid [4472]
    process[uav1/sitl_1-7]: started with pid [4473]
    process[uav1/iris_1_spawn-8]: started with pid [4474]
    process[uav1/mavros-9]: started with pid [4475]
    INFO [px4] Creating symlink /home/cactus/Firmware/ROMFS/px4fmu_common -> /home/cactus/.ros/sitl_iris_1/etc
    0 WARNING: setRealtimeSched failed (not run as root?)

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px4 starting.

INFO [px4] Calling startup script: /bin/sh etc/init.d-posix/rcS 1
INFO [dataman] Unknown restart, data manager file ‘./dataman’ size is 11798680 bytes
MAV_SYS_ID: curr: 1 -> new: 2
SYS_AUTOSTART: curr: 0 -> new: 10016
BAT_N_CELLS: curr: 0 -> new: 3
CAL_ACC0_ID: curr: 0 -> new: 1311244
CAL_ACC_PRIME: curr: 0 -> new: 1311244
CAL_GYRO0_ID: curr: 0 -> new: 2294028
CAL_GYRO_PRIME: curr: 0 -> new: 2294028
CAL_MAG0_ID: curr: 0 -> new: 197388
CAL_MAG_PRIME: curr: 0 -> new: 197388
CAL_BARO_PRIME: curr: 0 -> new: 6620172
COM_DISARM_LAND: curr: 2.0000 -> new: 0.1000
COM_OBL_ACT: curr: 0 -> new: 2
COM_OF_LOSS_T: curr: 0.0000 -> new: 5.0000
COM_RC_IN_MODE: curr: 0 -> new: 1
EKF2_ANGERR_INIT: curr: 0.1000 -> new: 0.0100
EKF2_GBIAS_INIT: curr: 0.1000 -> new: 0.0100
EKF2_REQ_GPS_H: curr: 10.0000 -> new: 0.5000
MC_PITCH_P: curr: 6.5000 -> new: 6.0000
MC_PITCHRATE_P: curr: 0.1500 -> new: 0.2000
MC_ROLL_P: curr: 6.5000 -> new: 6.0000
MC_ROLLRATE_P: curr: 0.1500 -> new: 0.2000
MPC_HOLD_MAX_Z: curr: 0.6000 -> new: 2.0000
INFO [simulator] Waiting for simulator to connect on TCP port 4560
MPC_Z_VEL_I: curr: 0.1000 -> new: 0.1500
MPC_Z_VEL_P: curr: 0.2000 -> new: 0.6000
MPC_XY_P: curr: 0.9500 -> new: 0.8000
MPC_XY_VEL_P: curr: 0.0900 -> new: 0.2000
MPC_XY_VEL_D: curr: 0.0100 -> new: 0.0160
MPC_JERK_MIN: curr: 8.0000 -> new: 10.0000
MPC_ACC_HOR_MAX: curr: 5.0000 -> new: 3.0000
NAV_ACC_RAD: curr: 10.0000 -> new: 2.0000
NAV_DLL_ACT: curr: 0 -> new: 2
RTL_DESCEND_ALT: curr: 30.0000 -> new: 5.0000
RTL_LAND_DELAY: curr: -1.0000 -> new: 5.0000
RTL_RETURN_ALT: curr: 60.0000 -> new: 30.0000
SDLOG_MODE: curr: 0 -> new: 1
SDLOG_PROFILE: curr: 3 -> new: 131
SDLOG_DIRS_MAX: curr: 0 -> new: 7
SENS_BOARD_X_OFF: curr: 0.0000 -> new: 0.0000
SENS_DPRES_OFF: curr: 0.0000 -> new: 0.0010
TRIG_INTERFACE: curr: 4 -> new: 3

  • RTL_DESCEND_ALT: curr: 5.0000 -> new: 10.0000
  • RTL_LAND_DELAY: curr: 5.0000 -> new: 0.0000
    process[uav2/sitl_2-10]: started with pid [4621]
    PWM_MAX: curr: 2000 -> new: 1950
    process[uav2/iris_2_spawn-11]: started with pid [4624]
    PWM_MIN: curr: 1000 -> new: 1075
    process[uav2/mavros-12]: started with pid [4629]
    INFO [px4] Creating symlink /home/cactus/Firmware/ROMFS/px4fmu_common -> /home/cactus/.ros/sitl_iris_2/etc
    0 WARNING: setRealtimeSched failed (not run as root?)

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| |
| | / /^\ \ ___ |
_| / / |_/

px4 starting.

INFO [px4] Calling startup script: /bin/sh etc/init.d-posix/rcS 2
MAV_SYS_ID: curr: 1 -> new: 3
SYS_AUTOSTART: curr: 0 -> new: 10016
BAT_N_CELLS: curr: 0 -> new: 3
CAL_ACC0_ID: curr: 0 -> new: 1311244
CAL_ACC_PRIME: curr: 0 -> new: 1311244
CAL_GYRO0_ID: curr: 0 -> new: 2294028
CAL_GYRO_PRIME: curr: 0 -> new: 2294028
CAL_MAG0_ID: curr: 0 -> new: 197388
CAL_MAG_PRIME: curr: 0 -> new: 197388
CAL_BARO_PRIME: curr: 0 -> new: 6620172
COM_DISARM_LAND: curr: 2.0000 -> new: 0.1000
COM_OBL_ACT: curr: 0 -> new: 2
COM_OF_LOSS_T: curr: 0.0000 -> new: 5.0000
COM_RC_IN_MODE: curr: 0 -> new: 1
EKF2_ANGERR_INIT: curr: 0.1000 -> new: 0.0100
EKF2_GBIAS_INIT: curr: 0.1000 -> new: 0.0100
EKF2_REQ_GPS_H: curr: 10.0000 -> new: 0.5000
MC_PITCH_P: curr: 6.5000 -> new: 6.0000
MC_PITCHRATE_P: curr: 0.1500 -> new: 0.2000
MC_ROLL_P: curr: 6.5000 -> new: 6.0000
MC_ROLLRATE_P: curr: 0.1500 -> new: 0.2000
MPC_HOLD_MAX_Z: curr: 0.6000 -> new: 2.0000
MPC_Z_VEL_I: curr: 0.1000 -> new: 0.1500
MPC_Z_VEL_P: curr: 0.2000 -> new: 0.6000
MPC_XY_P: curr: 0.9500 -> new: 0.8000
MPC_XY_VEL_P: curr: 0.0900 -> new: 0.2000
MPC_XY_VEL_D: curr: 0.0100 -> new: 0.0160
MPC_JERK_MIN: curr: 8.0000 -> new: 10.0000
MPC_ACC_HOR_MAX: curr: 5.0000 -> new: 3.0000
NAV_ACC_RAD: curr: 10.0000 -> new: 2.0000
NAV_DLL_ACT: curr: 0 -> new: 2
RTL_DESCEND_ALT: curr: 30.0000 -> new: 5.0000
RTL_LAND_DELAY: curr: -1.0000 -> new: 5.0000
RTL_RETURN_ALT: curr: 60.0000 -> new: 30.0000
SDLOG_MODE: curr: 0 -> new: 1
SDLOG_PROFILE: curr: 3 -> new: 131
SDLOG_DIRS_MAX: curr: 0 -> new: 7
SENS_BOARD_X_OFF: curr: 0.0000 -> new: 0.0000
SENS_DPRES_OFF: curr: 0.0000 -> new: 0.0010
TRIG_INTERFACE: curr: 4 -> new: 3

  • RTL_DESCEND_ALT: curr: 5.0000 -> new: 10.0000
  • RTL_LAND_DELAY: curr: 5.0000 -> new: 0.0000
    PWM_MAX: curr: 2000 -> new: 1950
    PWM_MIN: curr: 1000 -> new: 1075
    INFO [dataman] Unknown restart, data manager file ‘./dataman’ size is 11798680 bytes
    INFO [simulator] Waiting for simulator to connect on TCP port 4561
    INFO [dataman] Unknown restart, data manager file ‘./dataman’ size is 11798680 bytes
    INFO [simulator] Waiting for simulator to connect on TCP port 4562
    [ INFO] [1576591016.361221688]: Finished loading Gazebo ROS API Plugin.
    [ INFO] [1576591016.363314526]: waitForService: Service [/gazebo/set_physics_properties] has not been advertised, waiting…
    [ INFO] [1576591016.363458263]: Finished loading Gazebo ROS API Plugin.
    [ INFO] [1576591016.365142964]: waitForService: Service [/gazebo/set_physics_properties] has not been advertised, waiting…
    INFO [init] Mixer: etc/mixers/quad_w.main.mix on /dev/pwm_output0
    INFO [mavlink] mode: Normal, data rate: 4000000 B/s on udp port 14570 remote port 14550
    INFO [init] Mixer: etc/mixers/quad_w.main.mix on /dev/pwm_output0
    INFO [mavlink] mode: Normal, data rate: 4000000 B/s on udp port 14571 remote port 14550
    INFO [mavlink] mode: Onboard, data rate: 4000000 B/s on udp port 14580 remote port 14540
    INFO [mavlink] mode: Onboard, data rate: 4000000 B/s on udp port 14581 remote port 14541
    INFO [logger] logger started (mode=all)
    INFO [mavlink] MAVLink only on localhost (set param MAV_BROADCAST = 1 to enable network)
    INFO [px4] Startup script returned successfully
    INFO [logger] Start file log (type: full)
    INFO [logger] Opened full log file: ./log/2019-12-17/13_56_56.ulg
    INFO [logger] logger started (mode=all)
    INFO [mavlink] MAVLink only on localhost (set param MAV_BROADCAST = 1 to enable network)
    INFO [px4] Startup script returned successfully
    INFO [init] Mixer: etc/mixers/quad_w.main.mix on /dev/pwm_output0
    INFO [logger] Start file log (type: full)
    INFO [logger] Opened full log file: ./log/2019-12-17/13_56_56.ulg
    INFO [mavlink] mode: Normal, data rate: 4000000 B/s on udp port 14572 remote port 14550
    INFO [mavlink] mode: Onboard, data rate: 4000000 B/s on udp port 14582 remote port 14542
    INFO [logger] logger started (mode=all)
    INFO [mavlink] MAVLink only on localhost (set param MAV_BROADCAST = 1 to enable network)
    INFO [px4] Startup script returned successfully
    INFO [logger] Start file log (type: full)
    INFO [logger] Opened full log file: ./log/2019-12-17/13_56_56.ulg
    X Error of failed request: BadDrawable (invalid Pixmap or Window parameter)
    Major opcode of failed request: 153 (DRI2)
    Minor opcode of failed request: 3 (DRI2CreateDrawable)
    Resource id in failed request: 0x5000002
    Serial number of failed request: 31
    Current serial number in output stream: 33
    terminate called after throwing an instance of ‘boost::exception_detail::clone_impl<boost::exception_detail::error_info_injectorboost::lock_error >’
    terminate called recursively
    [ INFO] [1576591018.320433254]: FCU URL: udp://:14542@localhost:14582
    [ INFO] [1576591018.320869191]: FCU URL: udp://:14540@localhost:14580
    [ INFO] [1576591018.326274336]: FCU URL: udp://:14541@localhost:14581
    [ INFO] [1576591018.381503746]: udp0: Bind address: 0.0.0.0:14540
    [ INFO] [1576591018.381503700]: udp0: Bind address: 0.0.0.0:14541
    [ INFO] [1576591018.381661067]: udp0: Remote address: 127.0.0.1:14580
    [ INFO] [1576591018.381661099]: udp0: Remote address: 127.0.0.1:14581
    [ INFO] [1576591018.382016399]: GCS bridge disabled
    [ INFO] [1576591018.382016316]: GCS bridge disabled
    [ INFO] [1576591018.382715171]: udp0: Remote address: 127.0.0.1:14581
    [ INFO] [1576591018.382874285]: udp0: Bind address: 0.0.0.0:14542
    [ INFO] [1576591018.383014773]: udp0: Remote address: 127.0.0.1:14582
    [ INFO] [1576591018.383409180]: GCS bridge disabled
    [ INFO] [1576591018.384544989]: udp0: Remote address: 127.0.0.1:14580
    [ INFO] [1576591018.385339728]: udp0: Remote address: 127.0.0.1:14582
    [ INFO] [1576591019.872125894]: Plugin 3dr_radio loaded
    [ INFO] [1576591019.873127076]: Plugin 3dr_radio loaded
    [ INFO] [1576591019.874003249]: Plugin 3dr_radio loaded
    [ INFO] [1576591019.880313982]: Plugin 3dr_radio initialized
    [ INFO] [1576591019.880490313]: Plugin actuator_control loaded
    [ INFO] [1576591019.882053074]: Plugin 3dr_radio initialized
    [ INFO] [1576591019.882223703]: Plugin actuator_control loaded
    [ INFO] [1576591019.884616579]: Plugin 3dr_radio initialized
    [ INFO] [1576591019.884792018]: Plugin actuator_control loaded
    [ INFO] [1576591019.923093371]: Plugin actuator_control initialized
    [ INFO] [1576591019.924962199]: Plugin actuator_control initialized
    [ INFO] [1576591019.927829306]: Plugin actuator_control initialized
    [ INFO] [1576591020.561324570]: Plugin adsb loaded
    [ INFO] [1576591020.562053067]: Plugin adsb loaded
    [ INFO] [1576591020.562647146]: Plugin adsb loaded
    [ INFO] [1576591020.581928382]: Plugin adsb initialized
    [ INFO] [1576591020.582182351]: Plugin altitude loaded
    [ INFO] [1576591020.584590969]: Plugin adsb initialized
    [ INFO] [1576591020.584826417]: Plugin altitude loaded
    [ INFO] [1576591020.586106779]: Plugin adsb initialized
    [ INFO] [1576591020.586361523]: Plugin altitude loaded
    [ INFO] [1576591020.591784568]: Plugin altitude initialized
    [ INFO] [1576591020.592002297]: Plugin cam_imu_sync loaded
    [ INFO] [1576591020.593886748]: Plugin altitude initialized
    [ INFO] [1576591020.594168116]: Plugin cam_imu_sync loaded
    [ INFO] [1576591020.596847127]: Plugin altitude initialized
    [ INFO] [1576591020.597066388]: Plugin cam_imu_sync loaded
    [ INFO] [1576591020.598400784]: Plugin cam_imu_sync initialized
    [ INFO] [1576591020.598676568]: Plugin command loaded
    [ INFO] [1576591020.599927321]: Plugin cam_imu_sync initialized
    [ INFO] [1576591020.600203164]: Plugin command loaded
    [ INFO] [1576591020.602555488]: Plugin cam_imu_sync initialized
    [ INFO] [1576591020.602822019]: Plugin command loaded
    [ INFO] [1576591020.638494848]: Plugin command initialized
    [ INFO] [1576591020.638732520]: Plugin companion_process_status loaded
    [ INFO] [1576591020.648379278]: Plugin command initialized
    [ INFO] [1576591020.648624437]: Plugin companion_process_status loaded
    [ INFO] [1576591020.651269253]: Plugin command initialized
    [ INFO] [1576591020.651482671]: Plugin companion_process_status loaded
    [ INFO] [1576591020.658957581]: Plugin companion_process_status initialized
    [ INFO] [1576591020.659192406]: Plugin debug_value loaded
    [ INFO] [1576591020.677083376]: Plugin companion_process_status initialized
    [ INFO] [1576591020.677300284]: Plugin debug_value loaded
    [ INFO] [1576591020.680868095]: Plugin companion_process_status initialized
    [ INFO] [1576591020.681078455]: Plugin debug_value loaded
    [ INFO] [1576591020.711687806]: Plugin debug_value initialized
    [ INFO] [1576591020.711737861]: Plugin distance_sensor blacklisted
    [ INFO] [1576591020.712043779]: Plugin fake_gps loaded
    [ INFO] [1576591020.751899984]: Plugin debug_value initialized
    [ INFO] [1576591020.751951684]: Plugin distance_sensor blacklisted
    [ INFO] [1576591020.752237052]: Plugin fake_gps loaded
    [ INFO] [1576591020.755608603]: Plugin debug_value initialized
    [ INFO] [1576591020.755685971]: Plugin distance_sensor blacklisted
    [ INFO] [1576591020.756395616]: Plugin fake_gps loaded
    [ INFO] [1576591020.879287620]: Plugin fake_gps initialized
    [ INFO] [1576591020.879659834]: Plugin ftp loaded
    [ INFO] [1576591020.906274721]: Plugin fake_gps initialized
    [ INFO] [1576591020.906629353]: Plugin ftp loaded
    [ INFO] [1576591020.913272635]: Plugin fake_gps initialized
    [ INFO] [1576591020.913604768]: Plugin ftp loaded
    [ INFO] [1576591021.013427040]: Plugin ftp initialized
    [ INFO] [1576591021.013682935]: Plugin global_position loaded
    [ INFO] [1576591021.015482715]: Plugin ftp initialized
    [ INFO] [1576591021.015763575]: Plugin global_position loaded
    [ INFO] [1576591021.017533608]: Plugin ftp initialized
    [ INFO] [1576591021.017837931]: Plugin global_position loaded
    [ INFO] [1576591021.174030596]: Plugin global_position initialized
    [ INFO] [1576591021.174255918]: Plugin gps_rtk loaded
    [ INFO] [1576591021.177411847]: Plugin global_position initialized
    [ INFO] [1576591021.177633836]: Plugin gps_rtk loaded
    [ INFO] [1576591021.180285905]: Plugin global_position initialized
    [ INFO] [1576591021.180485380]: Plugin gps_rtk loaded
    [ INFO] [1576591021.201930551]: Plugin gps_rtk initialized
    [ INFO] [1576591021.202336622]: Plugin hil loaded
    [ INFO] [1576591021.204178803]: Plugin gps_rtk initialized
    [ INFO] [1576591021.204450237]: Plugin hil loaded
    [ INFO] [1576591021.206633150]: Plugin gps_rtk initialized
    [ INFO] [1576591021.206889720]: Plugin hil loaded
    [ INFO] [1576591021.335408614]: Plugin hil initialized
    [ INFO] [1576591021.335763259]: Plugin home_position loaded
    [ INFO] [1576591021.341984693]: Plugin hil initialized
    [ INFO] [1576591021.342237945]: Plugin home_position loaded
    [ INFO] [1576591021.344051804]: Plugin hil initialized
    [ INFO] [1576591021.344400612]: Plugin home_position loaded
    [ INFO] [1576591021.370686711]: Plugin home_position initialized
    [ INFO] [1576591021.371125923]: Plugin imu loaded
    [ INFO] [1576591021.373087820]: Plugin home_position initialized
    [ INFO] [1576591021.373504428]: Plugin imu loaded
    [ INFO] [1576591021.386987659]: Plugin home_position initialized
    [ INFO] [1576591021.387346395]: Plugin imu loaded
    [ INFO] [1576591021.443305764]: Plugin imu initialized
    [ INFO] [1576591021.443553363]: Plugin landing_target loaded
    [ INFO] [1576591021.450703413]: Plugin imu initialized
    [ INFO] [1576591021.450945457]: Plugin landing_target loaded
    [ INFO] [1576591021.463008618]: Plugin imu initialized
    [ INFO] [1576591021.463346107]: Plugin landing_target loaded
    [ INFO] [1576591021.581349633]: Plugin landing_target initialized
    [ INFO] [1576591021.581618249]: Plugin local_position loaded
    [ INFO] [1576591021.584977127]: Plugin landing_target initialized
    [ INFO] [1576591021.585277953]: Plugin local_position loaded
    [ INFO] [1576591021.592329409]: Plugin landing_target initialized
    [ INFO] [1576591021.592600006]: Plugin local_position loaded
    [ INFO] [1576591021.699679797]: Plugin local_position initialized
    [ INFO] [1576591021.699932720]: Plugin log_transfer loaded
    [ INFO] [1576591021.704815092]: Plugin local_position initialized
    [ INFO] [1576591021.705149374]: Plugin log_transfer loaded
    [ INFO] [1576591021.732289217]: Plugin log_transfer initialized
    [ INFO] [1576591021.732579812]: Plugin manual_control loaded
    [ INFO] [1576591021.733393692]: Plugin local_position initialized
    [ INFO] [1576591021.733626230]: Plugin log_transfer loaded
    [ INFO] [1576591021.744588588]: Plugin log_transfer initialized
    [ INFO] [1576591021.744862102]: Plugin manual_control loaded
    [ INFO] [1576591021.759203172]: Plugin log_transfer initialized
    [ INFO] [1576591021.759556633]: Plugin manual_control loaded
    [ INFO] [1576591021.769686952]: Plugin manual_control initialized
    [ INFO] [1576591021.769917052]: Plugin mocap_pose_estimate loaded
    [ INFO] [1576591021.783222151]: Plugin manual_control initialized
    [ INFO] [1576591021.783554251]: Plugin mocap_pose_estimate loaded
    [ INFO] [1576591021.797205803]: Plugin manual_control initialized
    [ INFO] [1576591021.797647328]: Plugin mocap_pose_estimate loaded
    [ INFO] [1576591021.816264456]: Plugin mocap_pose_estimate initialized
    [ INFO] [1576591021.816510301]: Plugin mount_control loaded
    [ INFO] [1576591021.834380517]: Plugin mocap_pose_estimate initialized
    [ INFO] [1576591021.834691120]: Plugin mount_control loaded
    [ INFO] [1576591021.845590379]: Plugin mount_control initialized
    [ INFO] [1576591021.845934225]: Plugin obstacle_distance loaded
    [ INFO] [1576591021.855400716]: Plugin mocap_pose_estimate initialized
    [ INFO] [1576591021.855747173]: Plugin mount_control loaded
    [ INFO] [1576591021.879633732]: Plugin mount_control initialized
    [ INFO] [1576591021.879884320]: Plugin obstacle_distance loaded
    [ INFO] [1576591021.884496745]: Plugin obstacle_distance initialized
    [ INFO] [1576591021.884725254]: Plugin odom loaded
    [ INFO] [1576591021.886582310]: Plugin mount_control initialized
    [ INFO] [1576591021.886798477]: Plugin obstacle_distance loaded
    [ INFO] [1576591021.910835546]: Plugin obstacle_distance initialized
    [ INFO] [1576591021.911066823]: Plugin odom loaded
    [ INFO] [1576591021.932548787]: Plugin obstacle_distance initialized
    [ INFO] [1576591021.932783615]: Plugin odom loaded
    SpawnModel script started
    SpawnModel script started
    SpawnModel script started
    [ INFO] [1576591021.973332462]: Plugin odom initialized
    [ INFO] [1576591021.973712984]: Plugin param loaded
    [ INFO] [1576591021.988909796]: Plugin odom initialized
    [ INFO] [1576591021.989295740]: Plugin param loaded
    [ INFO] [1576591022.003635811]: Plugin param initialized
    [ INFO] [1576591022.003862728]: Plugin px4flow loaded
    [ INFO] [1576591022.013075641]: Plugin odom initialized
    [ INFO] [1576591022.013490458]: Plugin param loaded
    [ INFO] [1576591022.037524195]: Plugin param initialized
    [ INFO] [1576591022.037742956]: Plugin px4flow loaded
    [ INFO] [1576591022.048656378]: Plugin param initialized
    [ INFO] [1576591022.048892337]: Plugin px4flow loaded
    [INFO] [1576591022.069711, 0.000000]: Loading model XML from ros parameter
    [INFO] [1576591022.078878, 0.000000]: Waiting for service /gazebo/spawn_urdf_model
    [ INFO] [1576591022.102284520]: Plugin px4flow initialized
    [ INFO] [1576591022.102337100]: Plugin rangefinder blacklisted
    [ INFO] [1576591022.102663686]: Plugin rc_io loaded
    [ INFO] [1576591022.130817560]: Plugin px4flow initialized
    [ INFO] [1576591022.130871026]: Plugin rangefinder blacklisted
    [ INFO] [1576591022.131195681]: Plugin rc_io loaded
    [ INFO] [1576591022.133876515]: Plugin px4flow initialized
    [ INFO] [1576591022.133926718]: Plugin rangefinder blacklisted
    [ INFO] [1576591022.134256897]: Plugin rc_io loaded
    [ INFO] [1576591022.147715849]: Plugin rc_io initialized
    [ INFO] [1576591022.147765161]: Plugin safety_area blacklisted
    [ INFO] [1576591022.148011130]: Plugin setpoint_accel loaded
    [ INFO] [1576591022.167291962]: Plugin rc_io initialized
    [ INFO] [1576591022.167340491]: Plugin safety_area blacklisted
    [ INFO] [1576591022.167584199]: Plugin setpoint_accel loaded
    [ INFO] [1576591022.170582143]: Plugin rc_io initialized
    [ INFO] [1576591022.170634438]: Plugin safety_area blacklisted
    [ INFO] [1576591022.170901549]: Plugin setpoint_accel loaded
    [ INFO] [1576591022.176208304]: Plugin setpoint_accel initialized
    [ INFO] [1576591022.176609148]: Plugin setpoint_attitude loaded
    [ INFO] [1576591022.196225716]: Plugin setpoint_accel initialized
    [ INFO] [1576591022.196622658]: Plugin setpoint_attitude loaded
    [ INFO] [1576591022.199115775]: Plugin setpoint_accel initialized
    [ INFO] [1576591022.199520762]: Plugin setpoint_attitude loaded
    [INFO] [1576591022.271411, 0.000000]: Loading model XML from ros parameter
    [INFO] [1576591022.281837, 0.000000]: Waiting for service /gazebo/spawn_urdf_model
    [INFO] [1576591022.293799, 0.000000]: Loading model XML from ros parameter
    [INFO] [1576591022.307121, 0.000000]: Waiting for service /gazebo/spawn_urdf_model
    [ INFO] [1576591022.369686581]: Plugin setpoint_attitude initialized
    [ INFO] [1576591022.369686466]: Plugin setpoint_attitude initialized
    [ INFO] [1576591022.369686555]: Plugin setpoint_attitude initialized
    [ INFO] [1576591022.369955529]: Plugin setpoint_position loaded
    [ INFO] [1576591022.369958833]: Plugin setpoint_position loaded
    [ INFO] [1576591022.370049154]: Plugin setpoint_position loaded
    [ INFO] [1576591022.483454355]: Plugin setpoint_position initialized
    [ INFO] [1576591022.483743932]: Plugin setpoint_raw loaded
    [ INFO] [1576591022.489840810]: Plugin setpoint_position initialized
    [ INFO] [1576591022.490115564]: Plugin setpoint_raw loaded
    [ INFO] [1576591022.499249454]: Plugin setpoint_position initialized
    [ INFO] [1576591022.499609428]: Plugin setpoint_raw loaded
    [ INFO] [1576591022.551071684]: Plugin setpoint_raw initialized
    [ INFO] [1576591022.551567295]: Plugin setpoint_velocity loaded
    [ INFO] [1576591022.567133407]: Plugin setpoint_raw initialized
    [ INFO] [1576591022.567407147]: Plugin setpoint_velocity loaded
    [ INFO] [1576591022.587061410]: Plugin setpoint_raw initialized
    [ INFO] [1576591022.587343636]: Plugin setpoint_velocity loaded
    [ INFO] [1576591022.602886516]: Plugin setpoint_velocity initialized
    [ INFO] [1576591022.603379586]: Plugin sys_status loaded
    [ INFO] [1576591022.629538003]: Plugin setpoint_velocity initialized
    [ INFO] [1576591022.630049878]: Plugin sys_status loaded
    [ INFO] [1576591022.655085504]: Plugin setpoint_velocity initialized
    [ INFO] [1576591022.655721478]: Plugin sys_status loaded
    [ INFO] [1576591022.703563372]: Plugin sys_status initialized
    [ INFO] [1576591022.703939787]: Plugin sys_time loaded
    [ INFO] [1576591022.730445596]: Plugin sys_status initialized
    [ INFO] [1576591022.730803314]: Plugin sys_time loaded
    [ INFO] [1576591022.743053504]: Plugin sys_status initialized
    [ INFO] [1576591022.743358639]: Plugin sys_time loaded
    [ INFO] [1576591022.760730178]: TM: Timesync mode: MAVLINK
    [ INFO] [1576591022.772689039]: Plugin sys_time initialized
    [ INFO] [1576591022.773002160]: Plugin trajectory loaded
    [ INFO] [1576591022.804707331]: TM: Timesync mode: MAVLINK
    [ INFO] [1576591022.821365868]: TM: Timesync mode: MAVLINK
    [ INFO] [1576591022.821887722]: Plugin sys_time initialized
    [ INFO] [1576591022.822113215]: Plugin trajectory loaded
    [ INFO] [1576591022.828420549]: Plugin sys_time initialized
    [ INFO] [1576591022.828648304]: Plugin trajectory loaded
    [ INFO] [1576591022.829771701]: Plugin trajectory initialized
    [ INFO] [1576591022.830103591]: Plugin vfr_hud loaded
    [ INFO] [1576591022.832241877]: Plugin vfr_hud initialized
    [ INFO] [1576591022.832373727]: Plugin vibration blacklisted
    [ INFO] [1576591022.832625948]: Plugin vision_pose_estimate loaded
    [ INFO] [1576591022.862449467]: Plugin trajectory initialized
    [ INFO] [1576591022.862794453]: Plugin vfr_hud loaded
    [ INFO] [1576591022.866782100]: Plugin vfr_hud initialized
    [ INFO] [1576591022.866832960]: Plugin vibration blacklisted
    [ INFO] [1576591022.867057061]: Plugin vision_pose_estimate loaded
    [ INFO] [1576591022.872452207]: Plugin trajectory initialized
    [ INFO] [1576591022.872791769]: Plugin vfr_hud loaded
    [ INFO] [1576591022.876108685]: Plugin vfr_hud initialized
    [ INFO] [1576591022.876245154]: Plugin vibration blacklisted
    [ INFO] [1576591022.876505603]: Plugin vision_pose_estimate loaded
    [ INFO] [1576591022.901223286]: Plugin vision_pose_estimate initialized
    [ INFO] [1576591022.901477751]: Plugin vision_speed_estimate loaded
    [ INFO] [1576591022.937556256]: Plugin vision_pose_estimate initialized
    [ INFO] [1576591022.937882800]: Plugin vision_speed_estimate loaded
    [ INFO] [1576591022.941290805]: Plugin vision_speed_estimate initialized
    [ INFO] [1576591022.941702425]: Plugin waypoint loaded
    [ INFO] [1576591022.955303021]: Plugin vision_pose_estimate initialized
    [ INFO] [1576591022.955554820]: Plugin vision_speed_estimate loaded
    [ INFO] [1576591022.977943086]: Plugin vision_speed_estimate initialized
    [ INFO] [1576591022.978314324]: Plugin waypoint loaded
    [ INFO] [1576591022.981432021]: Plugin waypoint initialized
    [ INFO] [1576591022.981655794]: Plugin wheel_odometry blacklisted
    [ INFO] [1576591022.982037454]: Plugin wind_estimation loaded
    [ INFO] [1576591022.989209651]: Plugin wind_estimation initialized
    [ INFO] [1576591022.989382484]: Autostarting mavlink via USB on PX4
    [ INFO] [1576591022.989610527]: Built-in SIMD instructions: SSE, SSE2
    INFO [mavlink] partner IP: 127.0.0.1
    [ INFO] [1576591022.989815814]: Built-in MAVLink package version: 2019.9.9
    [ INFO] [1576591022.989904629]: Known MAVLink dialects: common ardupilotmega ASLUAV autoquad icarous matrixpilot paparazzi slugs standard uAvionix ualberta
    [ INFO] [1576591022.989987286]: MAVROS started. MY ID 1.240, TARGET ID 3.1
    [ INFO] [1576591022.993285422]: CON: Got HEARTBEAT, connected. FCU: PX4 Autopilot
    [ INFO] [1576591022.995032883]: Plugin vision_speed_estimate initialized
    [ INFO] [1576591022.995395622]: Plugin waypoint loaded
    [ INFO] [1576591023.021556946]: Plugin waypoint initialized
    [ INFO] [1576591023.021734158]: Plugin wheel_odometry blacklisted
    [ INFO] [1576591023.022009232]: Plugin wind_estimation loaded
    [ INFO] [1576591023.024955934]: Plugin wind_estimation initialized
    [ INFO] [1576591023.025155986]: Autostarting mavlink via USB on PX4
    [ INFO] [1576591023.025383323]: Built-in SIMD instructions: SSE, SSE2
    INFO [mavlink] partner IP: 127.0.0.1
    [ INFO] [1576591023.025470927]: Built-in MAVLink package version: 2019.9.9
    [ INFO] [1576591023.025560589]: Known MAVLink dialects: common ardupilotmega ASLUAV autoquad icarous matrixpilot paparazzi slugs standard uAvionix ualberta
    [ INFO] [1576591023.025641671]: MAVROS started. MY ID 1.240, TARGET ID 1.1
    [ INFO] [1576591023.028770567]: CON: Got HEARTBEAT, connected. FCU: PX4 Autopilot
    [ INFO] [1576591023.029479146]: Plugin waypoint initialized
    [ INFO] [1576591023.030797919]: Plugin wheel_odometry blacklisted
    [ INFO] [1576591023.031055642]: Plugin wind_estimation loaded
    [ INFO] [1576591023.034097980]: Plugin wind_estimation initialized
    [ INFO] [1576591023.034276714]: Autostarting mavlink via USB on PX4
    [ INFO] [1576591023.034526597]: Built-in SIMD instructions: SSE, SSE2
    [ INFO] [1576591023.034613431]: Built-in MAVLink package version: 2019.9.9
    [ INFO] [1576591023.034699140]: Known MAVLink dialects: common ardupilotmega ASLUAV autoquad icarous matrixpilot paparazzi slugs standard uAvionix ualberta
    [ INFO] [1576591023.034780151]: MAVROS started. MY ID 1.240, TARGET ID 2.1
    INFO [mavlink] partner IP: 127.0.0.1
    [ INFO] [1576591023.036754525]: CON: Got HEARTBEAT, connected. FCU: PX4 Autopilot
    Aborted (core dumped)
    [gazebo-2] process has died [pid 4228, exit code 134, cmd /home/cactus/catkin_ws/src/gazebo_ros_pkgs/gazebo_ros/scripts/gzserver -e ode /home/cactus/Firmware/Tools/sitl_gazebo/worlds/empty.world __name:=gazebo __log:=/home/cactus/.ros/log/12be4c92-20d5-11ea-b080-e4029be100e1/gazebo-2.log].
    log file: /home/cactus/.ros/log/12be4c92-20d5-11ea-b080-e4029be100e1/gazebo-2.log*

Have you made any changes to the gazebo world file or the roslaunch file?
You can inspect your log file to see if there is any better description of the error.

I haven’t made any changes in any files .another error i am facing is

[ERROR] [1576660337.023746659, 435.900000000]: ODOM: Ex: Could not find a connection between ‘local_origin_ned’ and ‘fcu’ because they are not part of the same tree.Tf has two or more unconnected trees.
i dont know how to resolve this either

This is a bug which is currently being worked on, however this error isn’t the cause to Gazebo crashing and the simulation will worked perfectly with this error. The error can be silenced by adding some code to your roslaunch file.

my offb_node is not working i thought it might be the reason

If you get a core dump then make sure to look at the logfiles which are referenced in your output. And try getting the core dump using ulimit -c unlimited and then open the core dump using gdb to get a backtrace.

actually i am new to this but let me implement you technique. i hope it works