EWOD cartridge position sensing when docked in EWOD instrument

A method of operating a microfluidic system;

• wherein the microfluidic system comprises:
• an electro-wetting on dielectric (EWOD) cartridge comprising an element array configured to receive liquid droplets, the element array comprising a plurality of individual array elements each including array element circuitry comprising sensing circuitry that is integrated into the array element circuitry;
• a microfluidic instrument that is configured to receive the EWOD cartridge and having an electrically conductive locator that is external to the EWOD cartridge;
• and
• a control system configured perform electrowetting operations by controlling actuation voltages applied to the element array to perform manipulation operations as to liquid droplets present on the element array;
• the method of operating comprising the steps of:
• reading an output from the sensing circuitry;
• determining a position of the locator relative to the element array based on the output;
• determining a misalignment of the EWOD cartridge relative to the microfluidic instrument based on the position of the locator;
• and
• adjusting a manipulation operation of a liquid droplet to compensate for the determined misalignment of the EWOD cartridge relative to the microfluidic instrument.

A non-transitory computer-readable medium storing program code which is executed by a processing device for controlling a microfluidic system;

• wherein the microfluidic system comprises an electro-wetting on dielectric (EWOD) cartridge comprising an element array configured to receive liquid droplets, the element array comprising a plurality of individual array elements each including array element circuitry comprising sensing circuitry that is integrated into the array element circuitry;
• and a microfluidic instrument that is configured to receive the EWOD cartridge and having an electrically conductive locator that is external to the EWOD cartridge;
• the processing device being configured to perform electrowetting operations by controlling actuation voltages applied to the element array to perform manipulation operations as to liquid droplets present on the element array;
• the program code being executable by the processing device to perform the steps of:
• reading an output from the sensing circuitry;
• determining a position of the locator relative to the element array based on the output;
• determining a misalignment of the EWOD cartridge relative to the microfluidic instrument based on the position of the locator;
• and
• adjusting a manipulation operation of a liquid droplet to compensate for the determined misalignment of the EWOD cartridge relative to the microfluidic instrument.