Method and apparatus for monitoring wet contact touchpads

A method to accurately detect the touch and the release of a wet contact touchpad by sampling rates of decreasing or increasing voltage sampled between rapidly occurring charging cycles, the method comprising the steps of:

• a. providing a wet contact touchpad, the touchpad having flexible spaced apart plates and water between the spaced apart plates;
• b. electronically connecting the touchpad plates to a charging source and charging the plates with a first voltage, so as to reach a second charge voltage between the plates, the second charge voltage being less than the first voltage;
• c. electrically disconnecting the plates from the charging source when the second charged voltage is reached;
• d. monitoring the voltage of the charge between the plates using an analog-to-digital converter (ADC);
• e. using a transistor switch arrangement to control the connection and disconnection of the charging source;
• and,
• f. detecting a “touch” when “n” number of sequential decreasing samples of the charge between the plates are detected.

A method to accurately detect the touch and the release of a wet contact touchpad by sampling rates of decreasing or increasing voltage sampled between rapidly occurring charging cycles, the method comprising the steps of:

• a. connecting a charger to the plates to charge the plates;
• b. disconnecting the charger from the plates after a selected time interval;
• c. measuring the charge voltage between the plates;
• d. recording the measured charge voltage;
• e. reconnecting the charger to the plates to recharge the plates;
• f. disconnecting the charger from the plates after the selected time;
• g. measuring the new charge voltage between the plates;
• h. comparing the new charge voltage to the recorded charge voltage to observe an increase or decrease in measured voltage after charging;
• i. recording the increase or decrease;
• and,
• j. detecting “n” consecutive increases or deceases so as to observe a “touch” event, wherein the “touch” event is defined as “n” consecutive decreases in charge voltage after charging and “release” is defined as “n” consecutive increases in charge voltage after charging.