On-Line Handwritten Character Recognition with 3D Accelerometer

We present a pen-style hardware and analysis software for the recognition of handwritten characters. The hardware has a 3-dimensional acceleration sensor, an amplifier, a microcontroller with AD converter and communication port, and does not need any touching screen. The algorithm software includes signal preprocessing, feature extraction, and classifier. Both hidden Markov model (HMM) and dynamic time warping (DTW) algorithms are implemented. For the experiments with 10 Arabic numerals the hardware and software system shows very high recognition rates, i.e., 100% and 90.8% for the writer-dependent and writer-independent cases, respectively. Although the database is quite small, it clearly demonstrates the usefulness of the acceleration-based handwritten character recognition system without touching screen or pad