Medication delivery devices, systems and methods

A medication delivery device comprising:

• a user interface for receiving an instruction to deliver medication into a user's skin;
• a needle cover comprising a retractable sheath mechanism axially movable between a first position and a second position configured to allow insertion of a needle into the user's skin, the retractable sheath mechanism comprising one or more skin sensors for detecting the user's skin;
• a controller configured to:
• in response to receiving the instruction, measuring, via the one or more skin sensors, a contact between the retractable sheath mechanism and the user's skin;
• determining whether the needle is inserted into the user's skin with a predetermined injection depth based on the measured contact;
• and
• in response to the needle being inserted into the user's skin with the predetermined injection depth, delivering medication into the user's skin, and
• in response to the needle not being inserted into the user's skin with the predetermined injection depth, presenting, via the user interface, a feedback to the user to adjust a position of the needle.

A method of using a medication delivery device, the method comprising:

• providing a needle carousel to support a plurality of needle capsules disposed around a carousel axis thereof, each needle capsule including a needle spring to suspend a needle between opposite ends of the respective needle capsules;
• rotating the needle carousel about the carousel axis to align the needle of one of the needle capsules to an injection end of the medication delivery device;
• engaging the needle with the injection end of the medication delivery device;
• extending the needle to project from a distal end of the respective needle capsules;
• and
• retracting the needle into the respective needle capsules.