Excel or .txt matrice une arduino ??? HELP !!

18 columns by 2000 rows is 36000 values. Even if they are all bytes, that is NOT going to fit in SRAM.

Your best bet is to save the data as a csv file, on an SD card, and add an SD card reader to the robot. Read a record, move the servos. Repeat until you get to the end of the file.

Then what? Does the robot just stop?