Extraction of the Analog Pentip Position, Velocity and Acceleration Signals from a Digitizer

Publisher Summary This chapter presents a hardware setup that can be connected to the output of a digitizer to obtain the analog pen-tip position, velocity, and acceleration signals almost simultaneously. These analog signals can then be digitized at a convenient sampling frequency for a computer data analysis. The electronic system is based on signal sampling and synthesis theory. When connected to a digitizer, the analog pen-tip position, velocity, and acceleration signals are generated almost instantaneously, thereby giving an immediate description of the dynamics of the handwriting movement that is taking place; these outputs are measured in an inertial reference system as opposed to the moving reference system that results in systems where transducers, such as accelerometers, are integrated in a pen. The simultaneous availability of this information might be of practical interest in experiments dealing with handwriting analysis and synthesis. A comparison between handwritten patterns and the corresponding static and dynamic representation of the analog pen-tip position signals shows an accurate match. The almost instantaneous availability of the pen-tip information is valuable for real-time handwriting analysis and recognition.