About movement and communication in General Posted March 18, 2014 Hello, I've got two beginners questions... 1) If I'd want to move a robot by a specific distance (however not be very precise), do I need wheels with encoders? Can't I somehow approximate the time I need to power the engine? I don't need to move exactly 1mm left or right. I've read about encoders, but they are too expensive for me. 2) If I wanted to control a robot from an Android app via bluetooth, could I send some data from the robot to my phone, process the data (on the phone) and send something (an instruction, lets say) back to the robot? Sorry for my English. Thanks in advance.