我是PX4的新手，我安装了凉亭，并克隆了固件。
我正在尝试发布ros主题。但是我得到了错误。
我遵循的步骤：
Terminal1：
roslaunch mavros px4.launch fcu_url:="udp://:14540@127.0.0.1:14557"
Terminal2：
source Tools/setup_gazebo.bash $(pwd)$(pwd)/build_posix_sitl_default
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:$(pwd)/Tools/sitl_gazebo
roslaunch px4 posix_sitl.launch
我得到的错误，
Terminal1：
[ WARN] [1493507102.919495629]: TM: Clock skew detected (-0.019824184 s). Hard syncing clocks.
[ERROR] [1493507113.704105243]: FCU: Accel #0 fail: TOUT!
[ERROR] [1493507113.706679234]: FCU: Gyro #0 fail: TOUT!
[ WARN] [1493507113.944251371]: TM: Clock skew detected(0.012025608 s). Hard syncing clocks.
[ERROR] [1493507121.030549466]: FCU: Accel #0 fail: TOUT!
[ERROR] [1493507121.036021491]: FCU: Gyro #0 fail: TOUT!
[ERROR] [1493507121.630152661]: FCU: Accel #0 fail: TOUT!
[ERROR] [1493507121.634544822]: FCU: Gyro #0 fail: TOUT!
[ERROR] [1493507122.108005687]: FCU: Accel #0 fail: TOUT!
[ERROR] [1493507122.111951530]: FCU: Gyro #0 fail: TOUT!
[ERROR] [1493507122.829282656]: FCU: Accel #0 fail: TOUT!
[ERROR] [1493507122.830428095]: FCU: Gyro #0 fail: TOUT!
[ WARN] [1493507141.422615369]: TM: Clock skew detected (-0.016021096 s). Hard syncing clocks.
Terminal2：
WARN [mavlink] [timesync] Hard setting offset.
WARN [mavlink] [timesync] Hard setting offset.
ERROR [sensors] Accel #0 fail: TOUT!
ERROR [sensors] Gyro #0 fail: TOUT!
WARN [mavlink] [timesync] Hard setting offset.
WARN [mavlink] [timesync] Hard setting offset.
WARN [mavlink] [timesync] Hard setting offset.
WARN [mavlink] [timesync] Hard setting offset.
WARN [mavlink] [timesync] Hard setting offset.
请帮助我解决这个问题。
谢谢！