On her blog, Dustyn Roberts presents her own experience on current sensing for controlling DC electric motors with an Arduino board and an Arduino Motor Shield. This shield, based on a L298 H-bridge, provides two current sensing pins to the user, which can be used to measure the instantaneous current absorpion by each H-bridge. After some trials, Dustyn managed to have a quite clear picture of the absorption behavior of the DC motor:
Sample code and updates can be found on Dustyn’s blog.
[Via: Dustyn's blog]