Touch-Screen Stimulation for Automated Verification of Touchscreen-Based Devices

This paper presents an approach to stimulation of the touch-screen as part of the automated system for smart phone and tablet verification. Stimulation is performed in two ways: by touching the screen with the long conductor connected to the ground and by stimulating the screen with orthogonal conductive lines. The conductor is disconnected from the screen electrically, with the use of a transistor. Controlling the on/off state of the transistor controls whether the conductor touches the screen or not. The capacitance of the conductor is enough to change the structure of the electric field such that the touch-screen controller senses the touch when the conductor is connected to the screen, which happens when the transistor is turned on. The system was tested using different touch areas. It showed a clear increase in touch frequency detected by the controller when the transistor is turned on.