Drug delivery measurement in a medicine delivery device

A method of drug delivery measurement, the method comprising:

• obtaining first measurement data at a sensor, the first measurement data indicative of a first distance between a dispensing piston and a surface of a cartridge of a medicine delivery device, wherein the surface of the cartridge is opposite the piston;
• providing the first measurement data to a processor of the medicine delivery device;
• and
• determining, using the processor, a volume of the medicine in the cartridge based on the measured first distance.

A non-transitory computer readable medium containing instructions that, when executed by a processor of a medicine delivery device, cause the processor to:

• obtain first measurement data from a sensor, the first measurement data indicative of a first distance between a dispensing piston and a surface of a cartridge of a medicine delivery device, wherein the surface of the cartridge is opposite the piston;
• determine a volume of the medicine in the cartridge based on the measured first distance;
• obtain second measurement data from the sensor, the second measurement data indicative of a second distance between the dispensing piston and the surface of the cartridge;
• and
• determine a volume of the dispensed medicine based on the first distance and the second distance.