Autoinjector for administering medicament

Disclosed herein is an autoinjector for administering a medicament, comprising: a housing; a cartridge receiver; a drive module coupled to move the plunger rod between a retracted plunger rod position and an extended plunger rod position, the plunger rod configured to move the first stop; and a processing unit coupled to the drive module wherein the processing unit is configured to: control the drive module to move the plunger rod at a mixing plunger rod speed from a first plunger rod position to a mixing plunger rod position, the mixing plunger rod position is selected to position the first stopper in a position where the first medicament component is mixed with the second medicament component; providing a start signal after a plurality of complete inversions of the autoinjector have been performed; and performing an air injection after a plurality of invertions have been performed, the air injection being performed only when the second cartridge chamber is directed upward compared to the first cartridge cha