Patent attributes
A substance delivery device engages with a reservoir, and includes a pump that draws therapeutic substance from the reservoir into a pump chamber of the delivery device without changing the internal dimensions of the reservoir. The volume of the therapeutic substance within the pump chamber varies in response to changes in the internal dimensions of the pump chamber. An orientation sensor generates an output indicating an orientation of the delivery device with respect to gravity. Control circuitry drives the pump to: calculate a volume of the substance within the reservoir, draw the substance into the pump chamber in response to (i) the calculated volume, in combination with (ii) an output from the orientation sensor that the delivery device is in an orientation that allows the substance to be drawn from the reservoir, and deliver the substance from the pump chamber to the subject. Other applications are also described.
