Touch Sensing with" Time Domain Reflectometry! - Medieninformatik
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T o u c h S e n s i n g w i t h T i m e D o m a i n R e f l e c t o m e t r y Student research project Markus Zimmermann ! 29.6.2010 Slide 1 LFE Medieninformatik • Markus Zimmermann Student research project Touch Sensing with Time Domain Reflectometry Advisor: Raphael Wimmer Professor: Prof. Dr. Heinrich Hußmann
Transcript of Touch Sensing with" Time Domain Reflectometry! - Medieninformatik
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 1!
LFE Medieninformatik • Markus Zimmermann!
Student research project!
Touch Sensing with"Time Domain Reflectometry!
Advisor: Raphael Wimmer!Professor: Prof. Dr. Heinrich Hußmann!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 2!
MOTIVATION!
MINIATURISED DEVICES!REQUIREMENTS FOR PROTOTYPES:!SMALL / ANY SHAPE / TANGIBLE / TOUCH RECOGNITION!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 3!
INTRODUCTION!TIME DOMAIN REFLECTOMETRY!
Source: Oleg Alexandrov [1]
DISCONTINUITY Capacitive / Inductive / Resistive
SIGNAL
Literature: Rako2007, Agilent2006, Cole1977, Schmitt1999
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 4!
PRESENT USAGE!•!Wiring maintainance"
communication, aviation!•!Agricultural and geotechnical"
moisture, slope movement!•!Semiconductor/circuit analysis!•!New Approach: "
Touch Sensing!
Illustrations: Photocase (toKi/pischare) [3,5], Businessweek [4], Tektronix [2]
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 5!
REFLECTIONS!TERMINATION!•! Short Circuit!
•! Open Circuit!
•! Matched Load!
DISCONTINUITIES!•! Shunt Capacitance!
•! Series Inductance!
•! Combinations of capacitive and inductive!
Source: Tektronix [2]
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 6!
HARDWARE: TEKTRONIX 1502!CHARACTERISTICS!•!1975!•!Peak: "
140 ps risetime!•!Resolution: "
10 mm separable!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 7!
SIGNAL ANALYSIS!
ACQUISITION! FILTER! SMOOTHING!
MAPPING! DETECTION! CALIBRATION!
STAGES!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 8!
1. ACQUISITION!FIREFLY!CAMERA CAPTURING!
OPENCV "IMAGE ANALYSIS!
MEASURED WIRE
DISCONTINUITY NOISE
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 9!
2. MOVING AVERAGE FILTER!•!HF peak
attenuation!•!Extrema better
locatable!•! Imagewise jitter
remains!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 10!
3. ADAPTIVE AVERAGE SMOOTHING!SIG
NAL V
ALUE TIM
E
FRAMEAVER
AGE
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 14!
APPLICATIONS!»NICE. BUT: HOW DOES IT FEEL?«!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 15!
»WIRE«!•!Unshielded "
two-core wire!•!Short-circuit
termination performs best!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 16!Source: Raphael Wimmer
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 17!
»SNAKE«!FIRST PCB DESIGN!•!coplanar waveguide!•!Behavior test"
Material"Insulation"Curves!
•!Raw with big gaps!•!Chi-Fang Huang
(Huang2009)!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 18!Source: Raphael Wimmer
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 19!
»HILBERT«!SPACE-FILLING
CURVE!•!Spatial resolution
increased!
MITRED BENDS!•!Reflections reduced!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 20!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 21!
USE CASES: OUTLOOK!•!Wiring 3D Objects!•!Transparent: ITO coating!•!Wearable: conductive twine!•!Gaming: guitar!•!Guidance: user tracing!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 22!
DISCUSSION!PROTOTYPING
TECHNIQUE!•!Noise!•!HF interferences!•!Limited resolution:"
A#ordable!•!Good resolution:"
Expensive!GSM/EDGE
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 23!
Touch Sensing with!Time Domain Reflectometry Student research project!
Markus Zimmermann ! 29.6.2010! Slide 24!
REFERENCES & SOURCES!•! Huang2006: Huang C, Hung Y. P-53: Precise Location of Touch Panel by Employing the
Time-Domain Reflectometry. SID Symposium Digest of Technical Papers. 2009.!•! Rako2007: Rako P. TDR: taking the pulse of signal integrity. Electronics Design,
Strategy, News. 2007.!•! Agilent2006: Agilent. Time Domain Reflectometry Theory. Agilent; 2006.!•! Cole1977: Cole RH. Time domain reflectometry. Annual review of physical chemistry.
1977;28(1):283-300.!•! Schmitt1999: Schmitt R. Analyze transmission lines with (almost) no math. EDN.
1999;44(6):143-150.!•! Tektronix2008: Tektronix. TDR Impedance Measurements : A Foundation for Signal
Integrity. Tektronix; 2008.!1.! http://de.wikipedia.org/w/index.php?title=Datei:Partial_transmittance.gif!2.! [Tektronix2008]!3.! http://www.photocase.com/de/photodetail.asp?i=59811!4.! http://images.businessweek.com/ss/06/08/wow_bridges/source/2.htm!5.! http://www.photocase.com/de/photodetail.asp?i=183023 !
