Systems, methods, and apparatus for dispensing a lubricant are provided, in which, for example, the apparatus includes a chamber having an inlet through which the lubricant is received and an outlet through which the lubricant is ejected. The apparatus also includes a piston movably positioned in the chamber to take lubricant into the chamber and eject it therefrom. The apparatus further includes a sensor configured to take a measurement of a condition related to a force applied to the piston to move the piston in the chamber. The apparatus additionally includes a controller coupled with the sensor so as to receive data related to the measurement from the sensor. The controller is configured to determine, using the measurement, an amount of lubricant ejected by the piston.