Efficient dynamic time warping for 3D handwriting recognition using gyroscope equipped smartphones

•This is the first smartphone demonstration study for 3D handwriting recognition.•A 3D gyroscope is superior to 3D accelerometers to recognize similar shaped letters.•A fast DTW reduced the computing cost of the recognition algorithm in mobile devices.

Handwriting character recognition from three-dimensional (3D) accelerometer data has emerged as a popular technique for natural human computer interaction. In this paper, we propose a 3D gyroscope-based handwriting recognition system that uses stepwise lower-bounded dynamic time warping, instead of conventional 3D accelerometer data. The results of experiments conducted indicate that our proposed method is more effective and efficient than conventional methods for user-independent recognition of the 26 lowercase letters in the English alphabet.