Keyboards of digital pianos havemoderate dynamic performance compared to that of grand pianos. Real needs emerged to emulate haptic features of a piano action by a simple device. This paper deals with analytical and experimental investigation of check and repetition phase of touch. Finding out the relationship among initial velocity of hammer, duration and magnitude of impact impulse, key position, fly of time gives sound foundation for development of a haptic keyboard that offers the same sensation for pianist as the acoustic one. Parameters of governing expressions were determined by measurements.