Touch simulation system and method

Abstract

Systems and methods provide for simulating an effective touch on a touch screen sensor. A touch screen sensor includes a first surface, an opposing second surface, and one or more electrodes disposed on or proximate to the second surface. Signals are applied to the first and second surfaces in a manner which results in a simulated touch to a particular location of the touch screen sensor. In another approach, a plurality of voltage drive signals are applied at various touch surface regions of the touch screen sensor. A current flow resulting from application of the voltage drive signals is detected as the simulated touch. Touch simulation can be initiated locally or remotely as part of automated monitoring, testing, calibration, and/or servicing procedures. Results of a touch simulation procedure can be acquired and used locally or remotely to assess the operational fitness of the touch screen sensor over time.

1 . A method of simulating a touch on a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface, the method comprising:
 applying a plurality of voltage drive signals at a plurality of regions of the touch screen sensor; and   detecting a current flow resulting from application of the plurality of voltage drive signals as the simulated touch.   
   
   
       2 . The method of  claim 1 , wherein the voltage drive signals have substantially equal amplitudes. 
   
   
       3 . The method of  claim 1 , wherein at least one of the voltage drive signals has an amplitude differing from others of the plurality of voltage drive signals. 
   
   
       4 . The method of  claim 1 , wherein detecting the current flow comprises detecting a change in a current flow at each of a plurality of corner regions of the first surface. 
   
   
       5 . The method of  claim 1 , further comprising detecting an impedance change between one corner region of the first surface relative to other corner regions of the first surface. 
   
   
       6 . The method of  claim 1 , wherein the voltage drive signals are applied to first, second, third, and fourth corners of the first surface, the first and second corners opposing the third and fourth corners, the method further comprising adjusting each of the voltage drive signals to a predetermined amplitude, and detecting an impedance responsive to the adjusted voltage drive signals. 
   
   
       7 . The method of  claim 6 , wherein the predetermined amplitude of the voltage drive signals respectively applied to the first and second corners is different from the predetermined amplitude of the voltage drive signals respectively applied to the third and fourth corners. 
   
   
       8 . The method of  claim 1 , wherein the applying and detecting processes are repeated over a duration of time, the method further comprising detecting variations in the current flow over the duration of time. 
   
   
       9 . The method of  claim 1 , wherein the applying and detecting processes are repeated over a duration of time, the method further comprising detecting a change in a position of the simulated touch over the duration of time. 
   
   
       10 . The method of  claim 9 , further comprising generating a message signal associated with the detected change in simulated touch position, and communicating the message signal to a remote location. 
   
   
       11 . The method of  claim 1 , further comprising receiving an initiation signal, and initiating the applying and detecting processes in response to the received initiation signal. 
   
   
       12 . The method of  claim 11 , wherein the initiation signal is received from a remote location or a location proximate the touch screen sensor. 
   
   
       13 . The method of  claim 11 , wherein the initiation signal is generated during a predetermined touch screen sensor routine. 
   
   
       14 . The method of  claim 1 , wherein a result of the simulated touch is compared to one or more predetermined limits, and the result exceeding the one or more predetermined limits is used to assess operational fitness of the touch screen sensor. 
   
   
       15 . The method of  claim 1 , wherein a current result of the simulated touch is compared to one or more previously measured results of the simulated touch, and the current result deviating from the previously measured results by a predetermined amount is used to assess operational fitness of the touch screen sensor. 
   
   
       16 . The method of  claim 1 , wherein a result of the simulated touch is used to compensate for inaccuracies of the touch screen sensor or a system incorporating the touch screen sensor. 
   
   
       17 . A touch sensing system, comprising:
 a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface; and   a controller coupled to the touch screen sensor, the controller configured to apply a plurality of voltage drive signals at a plurality of regions of the touch screen sensor, and detect a current flow resulting from application of the plurality of voltage drive signals as the simulated touch.   
   
   
       18 . The system of  claim 17 , wherein the controller maintains the voltage drive signals at substantially equal amplitudes. 
   
   
       19 . The system of  claim 17 , wherein the controller adjusts the amplitude of at least one of the voltage drive signals to an amplitude differing from an amplitude of others of the plurality of voltage drive signals. 
   
   
       20 . The system of  claim 17 , wherein the controller detects the current flow by detecting a change in a current flow at each of a plurality of corner regions of the first surface. 
   
   
       21 . The system of  claim 17 , wherein the controller detects an impedance change between one corner region of the first surface relative to other corner regions of the first surface. 
   
   
       22 . The system of  claim 17 , wherein the controller applies the voltage drive signals to first, second, third, and fourth corners of the first surface, the first and second corners opposing the third and fourth corners, the controller adjusting each of the voltage drive signals to a predetermined amplitude, and detecting an impedance responsive to the adjusted voltage drive signals. 
   
   
       23 . The system of  claim 22 , wherein the predetermined amplitude of the voltage drive signals respectively applied to the first and second corners is different from the predetermined amplitude of the voltage drive signals respectively applied to the third and fourth corners. 
   
   
       24 . The system of  claim 17 , wherein the controller repeats the applying and detecting processes over a duration of time, the controller detecting variations in the current flow over the duration of time. 
   
   
       25 . The system of  claim 17 , wherein the controller repeats the applying and detecting processes over a duration of time, the controller detecting a change in a position of the simulated touch over the duration of time. 
   
   
       26 . The system of  claim 25 , wherein the controller or a host processing system coupled to the controller generates a message signal associated with the detected change in simulated touch position, the message signal communicated to a remote location. 
   
   
       27 . The system of  claim 17 , wherein the controller receives an initiation signal from a remote source or a host processing system coupled to the controller, and controller initiating the applying and detecting processes in response to the received initiation signal. 
   
   
       28 . The system of  claim 27 , wherein the initiation signal is generated during a predetermined touch screen sensor routine or during a period of detected system idleness. 
   
   
       29 . The system of  claim 17 , wherein a result of the simulated touch is compared to one or more predetermined limits, and the result exceeding the one or more predetermined limits is used to assess operational fitness of the touch screen sensor. 
   
   
       30 . The system of  claim 17 , wherein a current result of the simulated touch is compared to one or more previously measured results of the simulated touch, and the current result deviating from the previously measured results by a predetermined amount is used to assess operational fitness of the touch screen sensor. 
   
   
       31 . The system of  claim 17 , wherein a result of the simulated touch is used to compensate for inaccuracies of the touch screen sensor or a system incorporating the touch screen sensor.