Abstract: A system and a method detects blockage of an actuating assembly in a drug delivery device with a brushless DC or stepper motor. The Back EMF voltage is periodically measured at the driving contacts of the motor. A blockage indication value is periodically calculated based on the divergence of voltages measured at different driving contacts, and an alarming and/or mitigation action is initiated if the blockage indication value meets a predefined criterion such as exceeding a minimum or maximum value.

Abstract: Monitoring an injection process executed by a variable dose injection device with feedback means for generating a number of feedback events proportionate to the dose to be determined is disclosed. A dialed or injected dose is determined by measuring a first signal of the process comprising a first signal peak related to a feedback event; detecting the first signal peak in the first signal; selecting an evaluation interval comprising the detected peak and adapted to an expected peak duration; deriving, from the first signal limited to the evaluation interval, a feature or characterizing parameter of the feedback event; identifying, from the derived feature, the feedback event as one of a dial up, dial down, or expel feedback event, and counting identified feedback events to determine the dialed or the ejected dose. The two-stage approach with serially executed peak detection and peak identification allows to optimize data storage and processing power.

Abstract: A flexible and reliable delivery state estimator or evaluator is provided for a drug delivery device. The proposed delivery status estimation architecture includes a position sensor that provides a continuous position sensor signal indicative of a current position of a component of the delivery device movable continuously from a first to a second component position, as well as a position discriminator that redefines the continuous position sensor signal to generate an approximate binary input signal on behalf of a state estimator. The discriminator absorbs any difficulty that may arise from a limited reproducibility or enhanced variability of the original continuous sensor signal, specifically including a user-originated signal spread in a movement of a needle protection sleeve of the delivery device.

Abstract: A patch delivery device includes a bottom housing part, a delivery element for subcutaneous delivery of a liquid to a patient, an adhesive patch for attaching the bottom housing part to the skin of the patient, a capacitive sensor with an electrode configuration including a plurality of skin contact sensitive electrodes, and a release liner covering a patient-side adhesive layer of the adhesive patch prior to adhering to the patient's skin. The release liner includes an electrically conductive area extending over at least a portion of the electrode configuration of the capacitive sensor before being removed from the adhesive patch. Providing the release liner with a conductive area gives rise to a discernible change in capacitive response of the sensor electrodes upon release liner removal that enables sensing a removal of a release liner covering a patient-side adhesive layer prior to attachment to the skin of a patient.