Auto injector with reconstitution handling support

1. An auto injector for administering a medicament, the auto injector comprising:

a housing;

a cartridge receiver configured to receive a cartridge comprising a first stopper, a second stopper, and a cartridge compartment containing the medicament, the cartridge compartment having a first cartridge subcompartment containing a first medicament component of the medicament and a second cartridge subcompartment containing a second medicament component of the medicament, the cartridge further comprising a bypass section providing fluid communication between the first cartridge subcompartment and the second cartridge subcompartment;

an orientation sensor configured to detect an orientation of the cartridge or an orientation of the auto injector or both;

a drive module coupled to move a plunger rod between a retracted plunger rod position and an extended plunger rod position, the plunger rod being configured to move the first stopper; 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 from a first plunger rod position to a mix plunger rod position with a mix plunger rod speed, wherein the mix plunger rod position is selected to position the first stopper in a position wherein the first medicament component is mixed with the second medicament component; and

provide an onset signal after a number of completed inversions of the auto injector has been performed;

wherein the cartridge receiver is configured to receive a cartridge assembly comprising the cartridge and a cartridge code feature, and the auto injector comprising a code sensor configured to read the cartridge code feature, and wherein the processing unit is coupled to the code sensor and further configured to receive from the code sensor a code signal indicative of the cartridge code feature, wherein the cartridge code feature defines the number of completed inversions required for the medicament in the cartridge.

2. The auto injector according to claim 1 , wherein the processing unit is configured to operate independently of a temperature of the medicament in the cartridge received in the cartridge receiver.

3. The auto injector according to claim 1 , wherein the onset signal is generated after the number of completed inversions of the auto injector has been performed and when the second cartridge subcompartment is pointing upwards compared to the first cartridge subcompartment.

4. The auto injector according to claim 1 , wherein the detecting of the auto injector inversions is implemented using the orientation sensor.

5. The auto injector according to claim 1 , wherein the orientation sensor comprises one or more accelerometers.

6. The auto injector according to claim 1 , wherein the orientation sensor comprises a tilt sensor, a tri-axial accelerometer, a single axis accelerometer, or a magnetometer or any combination thereof.

7. The auto injector according to claim 1 , wherein the orientation sensor comprises a tri-axial accelerometer.

8. The auto injector according to claim 1 , wherein the orientation sensor comprises a single or a multi axis gyroscope sensor.

9. The auto injector according to claim 8 , wherein the multi axis gyroscope sensor is a tri-axial gyroscope sensor.

10. The auto injector according to claim 1 , wherein the processing unit is further configured to control the drive module to move the plunger rod from the mix plunger rod position to a second plunger rod position when receiving the onset signal.

11. The auto injector according to claim 1 , wherein the processing unit is further configured to determine a first movement parameter based on a cumulative movement of the auto injector.

12. The auto injector according to claim 11 , wherein the first movement parameter is indicative of the number of completed inversions of the auto injector.

13. The auto injector according to claim 11 , wherein the first movement parameter is indicative of a frequency of movement of the auto injector.

14. The auto injector according to claim 1 , wherein an inversion is deemed a completed inversion by the auto injector if it is performed with an angular velocity above a default threshold.

15. The auto injector according to claim 14 , wherein the default threshold for the angular velocity is defined as an inversion frequency of at least 0.3 inversions per second.

16. The auto injector according to claim 14 , wherein the orientation sensor is configured to provide an angular velocity signal indicative of the angular velocity of the cartridge when the cartridge is received in the cartridge receiver.

17. The auto injector according to claim 1 , wherein the inversion is an inversion around an axis in a horizontal plane.

18. The auto injector according to claim 1 , wherein an inversion is deemed a completed inversion by the auto injector if it spans an angle above a default threshold.

19. The auto injector according to claim 18 , wherein the default threshold for the angle is at least 90 degrees.

20. The auto injector according to claim 18 , wherein a rotational motion of the auto injector from a start angular position to an end angular position is deemed a completed inversion by the auto injector if:

the start angular position is between a first vertical orientation with a distal end of the auto injector pointing upwards and a first horizontal position with the distal end of the auto injector pointing sideward along a horizontal axis;

the end angular position is between a second horizontal position with the distal end of the auto injector pointing sideward along a horizontal axis in a direction opposite that in the first horizontal position and second vertical orientation with the distal end of the auto injector pointing downwards, and

the default threshold for the angle between the first angular position and the second angular position is at least 90 degrees.

21. The auto injector according to claim 18 , wherein a rotational motion of the auto injector from a start angular position to an end angular position is deemed a completed inversion by the auto injector if:

the start angular position is between a first vertical orientation with a distal end of the auto injector pointing downwards and a first horizontal position with the distal end of the auto injector pointing sideward along a horizontal axis;

the end angular position is between a second horizontal position with the distal end of the auto injector pointing sideward along a horizontal axis in a direction opposite that in the first horizontal position and second vertical orientation with the distal end of the auto injector pointing upwards, and

the default threshold for the angle between the first angular position and the second angular position is at least 90 degrees.

22. The auto injector according to claim 1 , wherein the processing unit is further configured to provide a visible feedback or acoustic feedback or both to the user when the number of completed inversions has been performed, and/or for every completed inversion.

23. The auto injector according to claim 1 , wherein the processing unit is further configured to perform an air-shot after the number of inversions has been performed, wherein the air-shot is only performed when the second cartridge subcompartment is pointing upwards compared to the first cartridge subcompartment.

24. The auto injector according to claim 1 , wherein the threshold of the angular velocity or the threshold of the angle or both is defined by the auto injector or the cartridge code feature.

25. The auto injector according to claim 1 , wherein the number of completed inversions depends on the measured inversion angles and the angular velocity at which the inversions are executed manually by a user.