Arduino interface to MCS-12085/12086 Optical Mouse Sensor

Connect SDIO/SCLK to pins defined in mcs-12085.cpp and then call mcs12085_dx() and mcs12085_dy() to read distance mouse has moved since last call.

Procedure to run obstacle_expansion:

1.Create a catkin package named obstacle_expander (dependencies:message_runtime rospy jsk_recognition_msgs sensor_msgs geometry_msgs )

2.copy the three message files to msg folder and source files to scripts folder

3.edit the CMakelists