1. Touch Screen Linearity Tester Presented by Axis Inc.

2. Overview Z-Axis Mechanism Linearity and Skew Testing Protocol Physical Circuit Microcontroller User Interface Functionality

3. Z-Axis/Force Actuation

4. Linearity

5. Results From Manual Testing Linearity Data Confidence Intervals

6. Skew skew ratio =

7. Results From Manual Testing Skew DataConfidence Interval

8. Testing Protocol Force Actuation/Resistance Linearity/Skew

9. Physical Circuit

10. Voltage Divider ADC measures Voltage drop across known R1 Back Calculating To find Rtouch

11. Microcontroller The “Brain” of the system Receives Data from GUI Controls the Tests Reads Values from A/D Converter Sends Data back to GUI

12. Microcontroller (cont) Max127 A/D Converter RS232 for serial communication Motor controller card Photogates

13. User Interface Functionality

14. Action Items Data Acquisition and Control Circuit  Build and test low current circuit for data acquisition with micro controller  Streamline micro controller code  Modification to code for movement in x and y-axis simultaneously GUI  Integrate GUI with micro controller  Customize buttons on GUI  Manual jog of tester from GUI

15. Questions? Comments?