p3dx not communicating perfectly with laptop

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Hi, I am trying to do some work related to obstacle detection and avoidance using SICK laser scanner and p3dx robot. I was using the same 3 robots for the past one month. However, since the past two weeks the p3dx has stopped communicating with my laptop.

Once I run the command rosrun ROSARIA RosAria I get the following output:

Could not connect to simulator, connecting to robot through serial port /dev/ttyUSB0.
    Syncing 0
    Syncing 1
    Syncing 2
    Connected to robot.
    Name: Purdue_2051
    Type: Pioneer
    Subtype: p3dx
    ArConfig: Config version: 2.0
    Loaded robot parameters from p3dx.p
    ArRobotConnector: Connecting to MTX batteries (if neccesary)...
    ArRobotConnector: Connecting to MTX sonar (if neccesary)...
    [ INFO] [1387734063.988735382]: Setting TicksMM from ROS Parameter: 128
    [ INFO] [1387734063.992513924]: Setting DriftFactor from ROS Parameter: 0
    [ INFO] [1387734063.996264262]: Setting RevCount from ROS Parameter: 16570
    [ INFO] [1387734064.020029650]: RosAria: publishing new recharge state -1.
    [ INFO] [1387734064.020206305]: RosAria: publishing new motors state 0.
    [ INFO] [1387734064.102186591]: RosAria: publishing new motors state 1.

Now, if I check for rostopic list, i get the following:

/RosAria/battery_recharge_state
/RosAria/battery_state_of_charge
/RosAria/battery_voltage
/RosAria/bumper_state
/RosAria/cmd_vel
/RosAria/motors_state
/RosAria/parameter_descriptions
/RosAria/parameter_updates
/RosAria/pose
/RosAria/sonar
/rosout
/rosout_agg
/tf

However, if I try to publish any of the topics with Rosaria, say

rostopic echo /RosAria/pose

nothing happens. Even if I try to publish velocity commands, nothing happens and the robot does not move. But the SICK laser works fine and I can perform all necessary actions of obstacle detection for the stationary robot using the sensor. Can anyone please suggest what could be going wrong? Is there anything that I am missing or anything that I can do to debug this issue? Thanks a lot in advance.