I have just started working on Turtlebot1. I wanted to use keyboardteleop for moving turtlebot. I am using iRobot create base for this purpose (Kinect is not added). After executing command **roslaunch turtlebotbringup minimal.launch**, i get an error as-

[WARN] [WallTime: 1456226724.415139] Create : robot not connected yet, sci not available

and the turtlebot turns OFF. I turn ON turtlebot and execute command roslaunch turtlebotteleop keyboardteleop.launch. After this command, i get an error as-

[WARN] [WallTime: 1456227470.487644] Failed to read sensor package. 5 retries left. [WARN] [WallTime: 1456227485.445873] Could not load a calibration file for this turtlebot, it is recommended to run turtlebotcalibration to generate a new file. [WARN] [WallTime: 1456227485.446356] Search paths: FTF8TAG204036001.yaml , /home/rekha/.ros/turtlebotcreate/FTF8TAG204036001.yaml , /opt/ros/indigo/share/create_node/FTF8TAG204036001.yaml